Edinburgh University, Edinburgh
TRIUMF, Vancouver
Since the 1980s the nuclear physics community has pursued the development of intense and exotic radioactive ion beams for many areas of study including astrophysics. The myriad of radionuclides that exist fleetingly inside explosive stellar scenarios are involved in nuclear reactions which are extremely difficult to model from theory, and in these cases experimental data is crucial. The measurement problems of astrophysics often require not only the most sensitive detectors and most intense radioactive beams, but also the right combination of experimental facilities, accelerators and detectors. The community has tackled these problems in a variety of different ways, with many labs already active or coming online with new aggressive accelerator, isotope production and measurement technology ready to target the big astrophysics questions. This talk gives an overview of some experimental methods and facilities used to derive astrophysically-relevant nuclear properties and highlights the places in the world that perform these studies.
NSCL, East Lansing, Michigan
The 2007 Long Range Plan for Nuclear Science had as one of its highest recommendations the “construction of a Facility for Rare Isotope Beams (FRIB) a world-leading facility for the study of nuclear structure, reactions, and astrophysics. Experiments with the new isotopes produced at FRIB will lead to a comprehensive description of nuclei, elucidate the origin of the elements in the cosmos, provide an understanding of matter in the crust of neutron stars, and establish the scientific foundation for innovative applications of nuclear science to society.” A heavy-ion driver linac will be used to provide stable beams of >200 MeV/u at beam powers up to 400 kW that will be used to produce rare isotopes. Experiments can be done with rare isotope beams at velocities similar to the driver linac beam, at near zero velocities after stopping in a gas cell, or at intermediate (0.3 to 10 MeV/u) velocities through reacceleration. An overview of the design proposed for implementation on the campus of Michigan State University leveraging the existing infrastructure will be presented.
KEK, Ibaraki
KEK is studying the design of the superconducting final focus quadrupoles for the Super KEKB. The system consists of quadrupole-doublet cooled at 1.9 K. The vertical focusing quadrupole has the maximum magnetic field more than 8 T in the superconducting coils. The field gradient at the magnet center is more than 80 T/m and the effective magnetic length is 0.25 m. The horizontal focusing quadrupole is designed with the field gradient of 9.5 T/m and the effective magnetic length of 1.0 m. These magnet parameters will be iterated in the process of optimizing the beam optics. In this paper, the conceptual design of final focusing system and magnets will be reported.
ORNL, Oak Ridge, Tennessee
Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
3D computer simulations are performed to study magnetic field qualities in the SNS ring extraction Lambertson septum magnet. This work is motivated by the existence of a significant skew quad term in the magnet that has been identified as the source of causing a beam profile distortion on the target. The skew quad term is computed with different methods in simulations and is compared to measurement data. The origin of the large skew quad term is thoroughly investigated. The remedy for minimizing the skew quad term by modifying the magnet is also proposed. Particle tracking has been performed to verify the beam profile evolution through the existing and modified septum. The magnetic interference to the septum performance from an adjacent quadrupole is also assessed. This paper reports our simulation techniques and major results.
Fermilab, Batavia
Muons, Inc, Batavia
Funding: Supported in part by USDOE STTR Grant DE-FG02-07ER84825
This paper presents the results of design studies of a high field section of a helical cooling channel proposed for the 6D muon beam cooling. The results include the magnet aperture limitations, the tunability of field components, the field correction, the superconductor choice and the magnet operation margin.
USTC/NSRL, Hefei, Anhui
IHEP Beijing, Beijing
Titanium-Zirconium-Vanadium (TiZrV) nonevaporable getter (NEG), which can be fully activated after 4 hours heating at 200°;C, has been applied in many accelerators owing to the outstanding vacuum performance. In our experiments, TiZrV films have been deposited onto the inner face of stainless steel pipes via DC sputtering using argon gas as the sputtering gas. Samples have been investigated by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX) and X-ray Photoelectron Spectroscopy (XPS) to determine film composition and thickness, and by X-ray diffraction (XRD) to determine film structure and morphology. Second Electron Yields (SEY) of the TiZrV film have also been measured.
LBNL, Berkeley, California
Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
To uniformly heat targets to electron-volt temperatures for the study of warm dense matter, one strategy is to deposit most of the ion energy at the peak of energy loss (dE/dx) with a low (E < 5 MeV) kinetic energy beam and a thin target*. Lower mass ions have a peak dE/dx at a lower kinetic energy. To this end, a small lithium (Li+) alumino-silicate source has been fabricated, and its emission limit has been measured. These surface ionization sources are heated to {10}00-1150 C where they preferentially emit singly ionized alkali ions. Alumino-silicates sources of K+ and Cs+ have been used extensively in beam experiments, but there are additional challenges for the preparation of high-quality Li+ sources: There are tighter tolerances in preparing and sintering the alumino-silicate to the substrate to produce an emitter that gives uniform ion emission, sufficient current density and low beam emittance. We report on recent measurements of high ( up to 35 mA/cm2) current density from a Li+ source. Ion species identification of possible contaminants is being verified with a Wien (E x B) filter, and via time-of-flight.
*J.J. Barnard et al., Nuclear Instruments and Methods in Physics Research A 577 (2007) 275283.
PPPL, Princeton, New Jersey
HCL, Cambridge, Massachusetts
PU, Princeton, New Jersey
Funding: Research supported by the U.S. Department of Energy.
The evaluation of ion-atom charge-changing cross sections is needed for many accelerator applications. A classical trajectory Monte Carlo (CTMC) simulation has been used to calculate ionization and charge exchange cross sections. For benchmarking purposes, an extensive study has been performed for the simple case of hydrogen and helium targets in collisions with various ions. Despite the fact that the simulations only account for classical mechanics effects, the calculated values are comparable to the experimental results for projectile velocities in the region corresponding to the maximum cross section. Shortcomings of the CTMC method for multi-electron target atoms are also discussed.
Durham University, Durham
Cockcroft Institute, Warrington, Cheshire
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
DESY Zeuthen, Zeuthen
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
The University of Liverpool, Liverpool
Energy deposition in the conversion targets of positron sources for future linear colliders will lead to thermal shock waves which could limit the targets' lifetimes. For the International Linear Collider baseline source, we have studied the energy deposition in a target taking the higher harmonics of the undulator radiation fully into account and applying hydrodynamical models for the resulting heat flow to determine the thermal stress in the target and to assess its survivability.
KEK, Ibaraki
The first operation of the positron production with a tungsten single-crystal target has been performed at the positron source of the KEKB injector linac for the KEK B-factory (KEKB) from September 2006 to June 2007 (~10 months). Previously we carried out the systematic studies on the positron-production efficiencies with tungsten crystals having various thickness using 4- and 8-GeV electron beams at the test beam line during the term of 2000-2005. Finally, we optimized the thickness of the tungsten crystal at 4 GeV and developed both the target fabrication technique and the crystal-axis alignment technique in 2006. After the systematic studies, we installed a tungsten crystal target at the KEKB positron source without any significant modifications for the positron source. The data on the positron production, especially, the positron-production efficiencies and stabilities in terms of the primary electron and positron beams, were obtained during the nominal KEKB operation in this term. We summarize the long-term operational performance on the positron production with the tungsten crystal target at the KEKB injector linac in this report.
LAL, Orsay
IN2P3 IPNL, Villeurbanne
HU/AdSM, Higashi-Hiroshima
KEK, Ibaraki
CERN, Geneva
One of the main challenges for the future linear colliders projects (ILC and CLIC) is to design an efficient positron source taking into account the constraints imposed by the target heating. At present, different schemes have been analysed to produce high energy gammas and to convert them in an amorphous target. One of them considers the possibility to boost the energy of the backscattered photons of a laser pulse by Compton effect. This method is very attractive since the source is independent from the main Linac and since the photon helicity is conserved in Compton scattering and subsequently transferred to the produced pairs. This allows the physics experiments disposing of both positron and electron polarised sources. Different schemes have been proposed to provide the electron beam for the Compton collisions. taking into account the constraint imposed by the low value of the Thomson cross section. One of the explored possibilities is to design an ERL with relatively low repetition frequency, high charge per pulse and then to stack the produced positrons in an accumulation ring. Different considerations on this scheme will be illustrated and the main constraints discussed.
Muons, Inc, Batavia
Fermilab, Batavia
The study of rare processes using a beam of muons that stop in a target provides access to new physics at and beyond the reach of energy frontier colliders. The flux of stopping muons is limited by the pion production process and by stochastic processes in the material used to slow down the decay muons. Innovative muon beam collection and cooling techniques are applied to the design of stopping muon beams in order to provide better beams for such experiments. Such intense stopping beams will also support the development of applications such as muon spin resonance and muon-catalyzed fusion.
The University of Liverpool, Liverpool
Cockcroft Institute, Warrington, Cheshire
A model has been created in Geant4 to simulate the key elements of an undulator-based positron source for CLIC: the goal is to consider such a source as an alternative to the present baseline concept. The parameters of the undulator and capture device have been optimized for a range of operating scenarios. In each case we have calculated the rate of positron production, positron polarization and capture efficiency. We discuss the strengths and weaknesses of the undulator scheme in CLIC.
The University of Liverpool, Liverpool
Cockcroft Institute, Warrington, Cheshire
An undulator-based source has been chosen as a part of the baseline configuration for the International Linear Collider (ILC) to generate an intense beam of polarised positrons. A photon collimator placed between the undulator and the target can be used to adjust the size, intensity and polarisation of the photon beam impacting the target, and can also protect the target station and limit the activation of downstream components. In this paper, we calculate quantities such as the energy deposition, temperature change, activation and dose rate for different designs of the photon collimator, and consider the advantages and disadvantages for each case.
LBNL, Berkeley, California
Funding: This work was supported by the Office of Science, U. S. Department of Energy, under Contract No. DE-AC02-05CH11231.
There is considerable interest in the use of muon beams to create either an intense source of decay neutrinos aimed at a detector located 3000-7500 km away (a Neutrino Factory), or a Muon Collider that produces high-luminosity collisions at the energy frontier. R&D aimed at producing these facilities has been under way for more than 10 years. This paper will review experimental results from MuCool, MERIT, and MICE and indicate the extent to which they will provide proof-of-principle demonstrations of the key technologies required for a Neutrino Factory or Muon Collider. Progress in constructing components for the MICE experiment will be described.
Fermilab, Batavia
Muons, Inc, Batavia
We have developed a new method for capture, bunching and phase-energy rotation of secondary beams from a proton source, using high-frequency rf systems. The method is the baseline for muon capture in the International scoping study for a neutrino factory. In this method, a proton bunch on a target creates secondaries that drift into a capture transport channel. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. For the International Design Study the method must be optimized for performance and cost, and variations will be explored. In this paper we present results of optimization and variation studies toward obtaining the maximum number of muons for a neutrino factory, as well as for a future muon collider.
IPN, Orsay
INFN/LASA, Segrate (MI)
SCK-CEN, Mol
CEA, Gif-sur-Yvette
IAP, Frankfurt am Main
An Accelerator Driven System (ADS) for transmutation of nuclear waste typically requires a 600 MeV - 1 GeV accelerator delivering a proton flux of a few mA for demonstrators, and a few tens of mA for large industrial systems. Such a machine belongs to the category of the high-power proton accelerators, with an additional requirement for exceptional "reliability": because of the induced thermal stress to the subcritical core, the number of unwanted "beam-trips" should not exceed a few per year, a specification that is far above usual performance. This paper describes the reference solution adopted for such a machine, based on a so-called "fault-tolerant" linear superconducting accelerator, and presents the status of the associated R&D. This work is performed within the 6th Framework Program EC project "EUROTRANS".
ANL, Argonne
GANIL, Caen
Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.
We have developed and tested an X-ray based Bunch Length Detector (XBLD) for application in ion accelerators. X-rays produced as a result of ion beam interactions with matter are used to generate photoelectrons. The photoelectrons are analyzed by an rf deflector synchronized with the master oscillator, similar to the BLDs based on secondary electrons. The expected time resolution is several picoseconds. The proposed XBLD is particularly useful for the measurement of cw heavy-ion beams passing through a stripper foil or film in a high-power driver accelerator. The results of the XBLD commissioning and beam bunch profile measurements at the ANL heavy-ion cw ATLAS accelerator will be presented.
ORNL, Oak Ridge, Tennessee
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
Paul Scherrer Institute, Spallation Source Division, ASQ, Villigen PSI
There are three spallation neutron source facilities in the world with the potential of operating in the one megawatt proton beam power range. The SINQ facility at the Paul Scherrer Institut has already operated in this power range for several years with various water-cooled solid targets, and used a liquid metal (lead-bismuth) target for a period of four months in conducting its successful MEGAPIE project in 2006. The Spallation Neutron Source (SNS) facility at Oak Ridge National Laboratory began operation in 2006 and is approaching the one megawatt level using a liquid mercury target. The Japan Proton Accelerator Research Complex (J-PARC), which also has a mercury target, began beam-on-target operations in 2008 and is on its way to ramping-up its power level to one megawatt over the next few years. This paper will summarize the operating experience and planned improvements for the spallation targets at these megawatt class facilities.
PU, Princeton, New Jersey
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
ORNL, Oak Ridge, Tennessee
CERN, Geneva
BNL, Upton, Long Island, New York
Fermilab, Batavia
The MERIT (MERcury Intense Target) experiment was run in the fall of 2007 using 14 and 24 GeV intense proton beams from the CERN PS. It is a proof-of-principle experiment designed to validate a target concept for producing an intense muon source for a future muon collider or neutrino factory. The experiment successfully demonstrated a target technique for multi-MW proton beams that utilizes a free-flowing liquid metal jet within the confines of a high-field solenoid. We describe the experimental strategy and parameters, as well as the results obtained and their implications for future muon-based accelerator facilities.
FZJ, Jülich
CERN, Geneva
The COoler SYnchrotron COSY at the Forschungszentrum Jülich is operating now since 1992. Up to 5*1010 protons can be delivered over a momentum range of 600 MeV/c to 3.6 GeV/c. The prototype of the HESR barrier bucket cavity was installed into COSY and many measurements have been performed. Especially the co-operation of barrier bucket with stochastic cooling has been studied. During the measurements the internal WASA Pellet target was available which is similar to the PANDA target at the HESR. A 1.2m long cryo-tank has been designed and installed to measure the sensitivities of new pickup structures for the HESR stochastic cooling system. Tank design and structures arrangement correspond to the projected HESR stochastic cooling layout. The recent results will be presented.
KEK, Ibaraki
High-gradient RF breakdown studies have been in progress at Nextef (New X-band Test Facility at KEK) since 2006. To study the characteristics of different materials on high-field RF breakdown, we have performed high-gradient experiments by using narrow waveguides that has a field of around 140 MV/m at 50 MW power. Breakdown rates of stainless-steel and copper cases were measured and the results are described in this paper.
CLASSE, Ithaca, New York
Funding: Funding support from the National Science Foundation
X-ray beam production from a linac beam is investigated, especially emphasizing the optical matching flexibility that is possible with an external beam but not with a storage ring. Compared to existing storage ring light sources, a high energy linac (with or without recirculation) can produce monochromatic hard x-ray beams having comparable flux density, and far higher brilliance, than are available with existing storage rings. Full coherence and the possibility of diffraction limited focusing are preserved by avoiding the need for x-ray focusing mirrors.
INFN/LNF, Frascati (Roma)
Università di Roma I La Sapienza, Roma
INFN-Roma II, Roma
ELETTRA, Basovizza
Universita' degli Studi di Milano, Milano
Istituto Nazionale di Fisica Nucleare, Milano
A feasibility study for a dedicated beamline for a THz radiation source at SPARC is discussed. A radiofrequency electron gun followed by a compressor can generate trains of THz sub-picosecond electron pulses by illuminating the photocathode with a comb laser pulse. This structure of the beam can be used to produce coherent radiation. The quality of the coherent spectrum emitted by a comb beam is tightly connected to the electron micro-bunches lengths and to micro-pulses inter-distance. Beam dynamics studies are summarized here and compared to a conventional single bunch case, optimized for the THz radiation generation. The dynamics is studied within the SPARC system with the PARMELA code and with the RETAR code for the evaluation of the radiation.
ITEP, Moscow
All known ion beam transport systems for medical applications with or without GANTRY are very large, complicated and expensive. Its cost is comparable with accelerator facility itself. It stimulates search of beam transport and distribution systems that allow reducing their cost and sizes considerably keeping treatment efficiency. Two such transport system are considered in the present paper. The first one is based on bend magnets that are rotated around their center of mass with movement of patient in horizontal position around of magnets. The second one uses stationary magnets with movement of patient in horizontal position in vertical plane. It is shown that the proposed ion transport systems provide treatment efficiency comparable with GANTRY at considerably lower sizes, mechanical complexity and cost.
KAERI, Daejon
Kyungpook National University, Daegu
KIRAMS, Seoul
Funding: This work was perfomed as a part of the Proton Engineering Frontier Project and supported by the ministry of Education, Science and Technology of Korea.
A prototype LEPT(Low Energy Proton Therapy) system was developed and established at the MC-50 cyclotron in 2007. Some of the users of the PEFP (Proton Engineering Frontier Project) has been requiring a irradiation system for in-vivo experiments for the beam utilization in the fieds of medical and biological sciences. We are studying on the possibility of in-vivo experiments the prototype LEPT system. The LEPT system consists of collimators, range shifter, modulator for SOBP, dose meaurement system, etc. The energy and current from the cyclotron was 45 MeV and a few nA. For the in-vivo experiments accurate control of dose rate and penetration depth range is essential. The other important issue is how we can control the irradiation area and depth with high uniform dose distribution. We investigated the dose rate and uniformity of dose distribution inside the sample using PMMA and water phantom. The dose was measured by using ionization chamber and GAF films. The dose rate was 0.2~1Gy/sec and the penetration depth was 10~15 mm. The further studies using small animals using this LEPT system will be done by the users.
KAERI, Daejon
Samsung SDI Co. Ltd., Gyeonggi-do
Kyungpook National University, Daegu
SAMSUNG SDI CO. LTD, Gyeonggi-do
Funding: This work was performed as a part of the Proton Engineering Frontier Project supported by the Ministry of Education, Science and Technology of Korea.
The sample activation during proton beam irradiation sometimes interrupt the measurement and investigation of the instant changes of the samples after irradiation. During the experiments for nano particle fabrications with ~35MeV and ~20uA, we found that the samples was highly activated after the proton beam irradiation. To investigate the source of the rdadiation from the samples, we measured the energy spectrum of gamma ray using HPGe spectroscopy. The results was compared to the calculated results by the MCNP code simulation. The sample was small amount of heavy metal dispersed in enthanol in the beaker made of quartz.
TRIUMF, Vancouver
JLAB, Newport News, Virginia
The medical isotope Molybdenum-99 is presently used for 80-85% of all nuclear medicine procedures and is produced by irradiating highly enriched uranium U-235 targets in NRU reactors. It was recently proposed that an electron linac be used for the production of 99Mo via photo-fission of a natural uranium target coming from the excitation of the giant dipole resonance around 15 MeV. The photons can be produced using the braking radiation (“bremsstrahlung”) spectrum of an electron beam impinged on a high Z material. In this paper we present an alternate concept for the production of 99Mo which is also based on photo-fission of U-238, but where the ~15 MeV gamma-rays are produced by Compton backscattering of laser photons from relativistic electrons. We assume a laser wavelength of 330 nm, resulting in 485 MeV electron beam energy, and 10 mA of average current. Because the induced energy spread on the electron beam is a few percent, one may recover most of the electron beam energy, which substantially increases the efficiency of the system. The accelerator concept, based on a three-pass recirculation system with energy recovery, is described and efficiency estimates are presented.
LANL, Los Alamos, New Mexico
Funding: Work performed under the auspices of the U.S. Department of Energy, under contract W-7405-ENG-36.
The WNR facility at LANSCE is preparing for a set of proton induced cross section measurements in support of the LANL Isotope Production Program. To determine the best way to produce particular isotopes, it is necessary to measure the production rate’s energy dependence. The first measurements will use a 197-MeV proton beam, which prompted recovery of the facility’s ability to transport multiple energy proton beams simultaneously to different experimental areas to ensure that an 800-MeV beam is available for Proton Radiography or Ultra-Cold Neutron experiments while a sample is irradiated with a lower energy beam for the cross section measurements. The ability to change the beam energy pulse-to-pulse was built into the original accelerator controls, but the multiple energy controls were unused for over a decade and the system was re-commissioned for this effort. These experiments form part of an effort to establish a capability for the measurement of cross sections in the 197 to 800 MeV energy range. The experiments are expected to provide the needed data for activities that may develop into a unique isotope production capability to compliment the existing 100-MeV IPF facility.
UOR, Jaipur
IUAC, New Delhi
Swift Heavy Ion (SHI) induced modification at Metal/Si interfaces has emerged as an interesting field of research due to its large applications. In the present study we investigate SHI induced mixed molybdenum silicide film with ion fluences. The Molybdenum and Si thin thin films were deposited on Silicon substrates using e-beam evaporation at 10-8 torr vacuum. Thin films were irradiated with Au ions of energy 120 MeV to form molybdenum silicide. The samples were characterized by grazing incidence X-ray diffraction (GIXRD) technique for the identification of phase formation at the interface. Rutherford backscattering spectrometry (RBS) was used to investigate the elemental distribution in the films. The mixing rate calculations were made and the diffusivity values obtained leads to a transient melt phase formation at the interface according to thermal spike model.
LPSC, Grenoble
SCK-CEN, Mol
IPHC, Strasbourg Cedex 2
LPC, Caen
CEA Cadarache, Saint Paul Lez Durance
IPN, Orsay
GUINEVERE, Generator-of-Uninterrupted-Intense-NEutrons-at-the-lead-VEnus-REactor, is devoted to ADS feasibility studies and to investigate on-line reactivity monitoring, sub-criticality determination and operational procedures. It will couple a versatile neutron source to the VENUS-F lead core at the SCK·CEN site in Mol (Belgium). It is based on an electrostatic accelerator generating 14 MeV neutrons by bombarding a deuteron beam on a tritium target located in the reactor core. A new accelerator has been developed. It will produce alternatively 1 μs 250 keV deuteron pulses with adjustable repetition rate (40 mA peak), as well as continuous beam (1 mA) with programmable interruptions. Beam will be inserted vertically into the reactor core. The accelerator is designed to enable the vertical section of the beam line to be easily lifted out the reactor bunker for maintenance operations, target changes and core loading procedures. This paper will describe the design of the accelerator and its commissioning in Grenoble (France), before its transfer to the Belgian site. This work is performed within the 6th Framework Program EC project EUROTRANS.
Manchester University, Manchester
UMAN, Manchester
University of Huddersfield, Huddersfield
Nuclear power production can benefit from the development of more comprehensive alternatives for dealing with long-term radioactive waste. One such alternative is an accelerator-driven subcritical reactor (ADSR) which has been proposed for both energy production and for burning radioactive waste. Here we investigate the effects of the size of the ADSR spallation target on the total neutron yield integrated over the neutron energy and emission angle. The contribution to the total neutron yield from the (n, xn) neutron interactions is evaluated at proton beam energies between 0.4 and 2 GeV. Calculations have been carried out with the GEANT4 simulation code using the Liege intranuclear cascade model and the results are compared to the the LAHET/MCNP code package predictions.
TUB, Beijing
The preliminary experiments and three-dimensional (3D) particle-in-cell (PIC) simulations of terahertz (THz) coherent transition radiation (CTR) performed at the Accelerator Laboratory of Tsinghua University are reported in this paper. THz radiation is generated from the interactions of Titanium foil with the ultrashort electron beam produced by the photocathode RF gun. The frequency and power of radiation are measured with the Martin-Pupllet interferometer and Gollay Cell detector, respectively. The radiation characteristics depending on the foil properties are preliminarily studied with the experiments and PIC simulations. On the other hand, the distribution of radiation field pattern and energy are studied by numerical calculated, and those results are in agreement with the PIC simulations.
TUB, Beijing
IHEP Beijing, Beijing
CIAE, Beijing
ANL, Argonne
KEK, Tsukuba
Funding: Supported by the “985 Project” of the Minister of Education of China, CAS Bairen Init. (KJCX2-YW-N22), CAS Overseas Outstanding Youth Program, and the National Natural Science Foundation (10628510).
During the past decades, large-scale national neutron sources are developed in Asia, Europe, and USA. Complementing such efforts, compact hadron beam complexes and neutron sources intended for universities and industrial institutes are proposed and established. Responding to the demands in China for multidisciplinary researches and applications using pulsed neutrons and protons, hadron therapy and radiography, and accelerator-driven sub-critical reactor systems (ADS) for nuclear waste transmutation, we here propose a compact yet expandable accelerator complex based on a proton source, a 3 MeV RFQ linac, and a 22 MeV DTL linac. A Be target with solid methane and room-temperature water moderators serve 6 neutron stations for imaging/radiography, irradiation, SANS, engineering powder diffraction, instrumentation, and therapy. The proton platform serves multiple stations for bio-applications, fuel cell and nano-applications, and space irradiation and detection. A rapid cycling synchrotron subsequently accelerates the beam to up to 300 MeV for proton therapy and radiography. Following the DTL linac with a superconducting RF linac and a sub-critical reactor offers an ADS test facility.
GSI, Darmstadt
Laboratoire de Physique des Gaz et des Plasmas, Universite Paris-Sud, Orsay
IPCP, Chernogolovka, Moscow region
TU Darmstadt, Darmstadt
Universidad de Castilla-La Mancha, Ciudad Real
Studies of High Energy Density (HED) states in matter is one of the recently proposed important applications of intense particle beams. GSI Darmstadt is worldwide famous due to its unique accelerator facilities. Construction of the new accelerator FAIR, will enhance these capabilities many fold. During the past years, extensive theoretical work has been carried out to propose future HED physics experiments that could be carried out at FAIR. It is expected that the new heavy ion synchrotron, SIS100, will deliver a uranium beam with 1012 uranium ions that will be delivered in a single bunch, 50 – 100 ns long. Circular, elliptic and annular focal spots can be generated that will allow one to perform different type of HED physics experiments. This work has shown that using a special technique, named HIHEX, one may access those areas of the phase diagram that have never been accessed before. Using another experimental configuration, LAPLAS , it will be possible to generate physical conditions that are expected to exist in the interiors of the giant planets. Material properties under dynamic conditions can also be studied using a third experimental set up.
INFN - Gruppo Messina, S. Agata, Messina
Università di Messina, Messina
INFN-Cagliari, Monserrato (Cagliari)
INFN-Ferrara, Ferrara
At the Dipartimento di Fisica, Università di Messina, an X-ray source based on a 5 MeV electron linac has been designed. By means of the MCNP-4C2 code, several simulations have been performed to evaluate if the source can be used as a NDT device for material recognition purposes. In particular, being able to vary the electron beam energy for producing bremsstrahlung beams with different absorption, X-ray transmission through several materials and for different X-ray beams energy has been studied. First results have shown the capability of the system to distinguish dissimilar materials by properly choosing the X-ray beam end-point energy and processing the obtained transmission values. Since the uncertainties level in the material identification could be improved differentiating the response of the imaging system, a theoretical study has been performed to evaluate how X-ray beams obtained with different end-point energies, and eventually transmitted by properly chosen filters, are absorbed by different scintillators. The obtained results will be presented and discussed in order to give indications on the real chance to use the designed device for material recognition purposes.
IBS, Atlanta, Georgia
MEPhI, Moscow
In today’s turbulent and unsecure world, an X-ray radiographic image and a dual-energy Z-detection mapping of a container contents are needed to provide a reasonable level of port and border security. An interlaced dual-energy electron-beam linac has been developed for the use in cargo inspection systems to meet this growing need. Electron energy of the linac is software controllable from 3 to 15 MeV. Nominal operating energy levels of 4 and 9 MeV were chosen. The 9 MeV beam energy operating point is used for generating the X-ray radiographic image while 4 and 9 MeV beams are used for Z-detection mapping. The S-band linac has been calculated, designed, built and tested. Frequency repetition rate of alternating 4 and 9 MeV beams is 240 Hz. Pulse length is 10 μs. The beam energy in each beam pulse is over 10 J.
University of Huddersfield, Huddersfield
UMAN, Manchester
PSI, Villigen
CEA, Grenoble
STFC/RAL, Chilton, Didcot, Oxon
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
The current paper discusses possible designs for a high intensity stand alone muon source for muSR studies of condensed matter. In particular we shall focus upon the potential implementation of a new generation of high power but relatively compact and cost effective proton drivers based on non-scaling fixed field alternating gradient (ns-FFAG) accelerator technology. The technical issues which must be addressed are also considered.
University of Huddersfield, Huddersfield
STFC/RAL, Chilton, Didcot, Oxon
The pulsed muon channel of the ISIS facility at Rutherford Appleton Laboratory has been successfully commissioned and operated for many years as a tool for MuSR studies in condensed matter research. At the present time, the graphite target, of dimensions 50*50*7 mm oriented at 45 degrees to a proton beam of 800 MeV energy, gives 16000 surface muons per double proton pulse passing through the entrance aperture of the aluminium window which separates the muon beamlines from the main proton beam. Potential improvements to the target geometry, and optimisation of the design and estimated performance of the muon target are presented in this paper.
University of Huddersfield, Huddersfield
STFC/RAL, Chilton, Didcot, Oxon
MuSR science requires the availability of intense beams of polarised positive muons. At the ISIS pulsed muon facility at Rutherford Appleton Laboratory the muons are generated from a low Z thin slab graphite target inserted in the proton beam. We report on the use of the Monte Carlo simulation code Geant4 in simulations of the performance of the current muon target. The results are benchmarked against the experimental performance of the target.
Fermilab, Batavia
Funding: Work supported by Fermi Research Alliance, LLC under contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Currently Main Injector delivers 330KW of beam power at 120 GeV by using multi-batch slip stacking. The beam power is expected to increase to 400KW after installing clearing gap kickers to eliminate the injection kicker gap loss. The plan to increase the beam power to 700KW for NOvA and the role of MI in Project-X (2.1MW operation) will be discussed.
Fermilab, Batavia
The multi-batch slip stacking has been used for operation since January, 2008 and effectively increased proton intensity to the NuMI target by 50% in a MI cycle. The MI accepts 11 pulses at injection energy from the Booster and sends two pulses to Anti-proton production and nine to the NuMI beam line. The total beam power on a cycle was increased to 340 KW on average. We have been doing beam studies in order to increase the beam power to 400 kW and to control the beam loss. We also discuss 12 batch slip stacking scheme which is going to be used for future Neutrino experiments.
Fermilab, Batavia
Muons, Inc, Batavia
Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The use of existing Fermilab facilities to provide beams for two muon experiments –- the Muon to Electron Conversion Experiment (Mu2e) and the Muon g-2 Experiment –- is under consideration. Plans are being pursued to be able to perform these experiments following the completion of the Tevatron Collider Run II with no impact to the on-going Main Injector neutrino program by using spare Booster cycles to provide 8.9 GeV/c protons on target. Utilizing the beam lines and storage rings used today for antiproton accumulation, beams can be prepared for these experiments with minimal disruption, reconfiguration or expansion of the Fermilab accelerator infrastructure. The proposed operational scenarios and required alterations to the complex are described.
Imperial College of Science and Technology, Department of Physics, London
STFC/RAL, Chilton, Didcot, Oxon
Multi MW Proton Driver in the few GeV range are required for a neutron spallation source being studied in the framework of the ISIS upgrade at RAL and for the production of muon beam for a Neutrino Factory. Although the requirements for the time structure of proton beams are different, we investigate the possibility to share the proton driver between the two facilities. We assume the beam for both facilities is accelerated in a linac followed by rapid cycling synchrotron (RCS) at 50 Hz repetition rate to 3.2 GeV. One part of the bunch train after extraction from the RCS can be sent to the neutron production target and the other part of the extracted beam can be sent to another RCS, where further acceleration and final bunch compression can be performed to meet the specification of the Neutrino Factory target. The preliminary study of the final bunch compression is presented.
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
J-PARC, KEK & JAEA, Ibaraki-ken
In J-PARC, Materials and Life Science Facility (MLF) is aimed at promoting experiments using the world highest intensity pulsed neutron and muon beams which are produced at a thick mercury target and a thin carbon graphite target, respectively, by 3-GeV proton beams. The first beam was achieved at the target without significant beam loss. To obtain the beam profile at the target, we applied an activation technique by using thin aluminum foil. In order to obtain reliable profile, it is required that a small number of shots for the beam adjustment and the beam stability. Since beam monitors works very well located at the beam transport line even in the first beam, the beam centralization can be finished by very small number of shots. The stability of beam for each pulse is recognized to be smaller than 1 mm. After many shots of irradiation, the 2-D beam profile can be obtained. It is found that the observed profile shows good agreement with the prediction calculation including the beam scattering at the proton beam window. The beam emittance is measured by the MWPM. It is found that the rms-beam emittance agree with the calculation by the SIMPSONS.
Fermilab, Batavia
Run II has been ongoing since 2001. Peak luminosities in the Tevatron have increased from approximately 10×1030 cm-2ses-1 to 300×1030 cm-2ses-1 a factor of 30 improvement. A significant contributing factor in this remarkable progress is a greatly improved antiproton production capability. Since the beginning of Run II, the average antiproton accumulation rate has increased from 2×1010 p/hr to about 24×1010 p/hr. Peak antiproton stacking rates presently exceed 25×1010 p/hr. The antiproton stacking rate has nearly doubled in the last two years alone. A variety of improvements have contributed to the recent progress in antiproton production. The process of transferring antiprotons to the Recycler Ring for subsequent transfer to the collider has been significantly restructured and streamlined, allowing more time to be utilized for antiproton production. Improvements to the target station have greatly increased the antiproton yield from the production target. The performance of the Antiproton Source stochastic cooling systems has been enhanced by improvements to the cooling electronics, accelerator lattice optimization, and improved operating procedures.
FZJ, Jülich
BINP SB RAS, Novosibirsk
The design, construction and installation of a 2 MeV electron cooling system for COSY-Jülich is proposed to further boost the luminosity even with strong heating effects of high-density internal targets. In addition the 2 MeV electron cooler for COSY is intended to test some new features of the high energy electron cooler for HESR at FAIR in Darmstadt. The design of the 2 MeV electron cooler will be accomplished in cooperation with the Budker Institute of Nuclear Physics in Novosibirsk, Russia. A new developed prototype of the high voltage section, consisting of a gas turbine, magnetic coils and high voltage generator with electronics was successfully tested . Special emphasis is given to a voltage stability better than 10-4. First experiments with three combined high voltage sections, arranged in a SF6 pressurized gas tank are reported.
FZJ, Jülich
CNS, Saitama
CERN, Geneva
The High Energy Storage Ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at the GSI in Darmstadt will be built as an anti-proton cooler ring in the momentum range from 1.5 to 15 GeV/c. An important and challenging feature of the new facility is the combination of phase space cooled beams with internal targets. In addition to electron cooling transverse and longitudinal stochastic cooling are envisaged to accomplish these goals. A detailed numerical analysis of the Fokker-Planck equation for longitudinal filter and time-of-flight cooling including an internal target and intrabeam scattering has been carried out to demonstrate the stochastic cooling capability. Model predictions have been compared to experimental cooling results with internal targets at the COSY facility. Experimental results at COSY to compensate the large mean energy loss induced by an internal Pellet target similar to that being used by the PANDA experiment at the HESR with a barrier bucket cavity (BB) will be presented. Experimental tests of stochastic filter cooling with internal target and BB operation as well as expected cooling properties for the HESR are discussed.
CERN, Geneva
IN2P3 IPNL, Villeurbanne
INFN/LNL, Legnaro (PD)
Istituto Nazionale di Fisica Nucleare, Milano
The CNGS facility (CERN Neutrinos to Gran Sasso) aims at directly detecting muon-neutrino to tau-neutrino oscillations. An intense muon-neutrino beam (1017 muon-neutrino per day) is generated at CERN and directed over 732 km towards the Gran Sasso National Laboratory, LNGS, in Italy, where two large and complex detectors, OPERA and ICARUS, are located. After a brief overview of the facility, the major events since its commissioning in 2006 will be discussed. Emphasis will be given on the design challenges and operation constraints coupled to such a high-intensity facility summarizing the acquired experience. Highlights of the 2008 operations, which was the first complete year of physics in CNGS with 1.78·1019 protons delivered on target, will be presented.
BNL, Upton, Long Island, New York
CEA, Gif-sur-Yvette
ESS-S, Lund
Fermilab, Batavia
CERN, Geneva
Funding: ESS-S Scandinavia Consortium
The conceptual design of the European Spallation Source-Scandinavia (ESS-S) is presented. The accelerator system baseline draws heavily on state-of-the-art mature technologies that are being employed in the CERN Linac4 and SPL projects, although advances with spoke resonator and sputtered superconducting cavities are also being evaluated for reliable performance. Irradiation damage due to proton beam losses is a key issue for linac and target components. Their optimized design is performed from an engineering perspective, using the last updated versions of mechanical design codes which were already qualified for irradiated components. Finally, future upgrades of power and intensity of the proton linac are considered, including the design optimization of the Target Station (proton/neutron convertor), with the possibility of increasing the average pulsed power deposition up to 7.5 MW. All possible upgrades will be taken into account for the final design review, in the frame of the costs and constraints given with the site decision.
CEA, Arpajon
A 15 MeV accelerator scheme based on a DC photo-injector and a RF superconducting linac has been proposed as a new facility for radiography applications. The design of a 15 MeV, 2 kA peak current, electron accelerator for the DEINOS project is presented The beam operating condition is a limited number of bunches up to twenty electron micro-pulses of 100 ps time duration and 200 nC bunch charge emitted at 352 MHz repetition rate from a Cs2Te photocathode and accelerated to 2.5 MeV in the DC diode before injection into a superconducting linac. A general description of the main accelerator components and the beam dynamics simulations are presented. The overall beam dynamics simulation process based on LANL POISSON-SUPERFISH and PARMELA codes and the results will be reviewed.
CERN, Geneva
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
ORNL, Oak Ridge, Tennessee
BNL, Upton, Long Island, New York
PU, Princeton, New Jersey
Fermilab, Batavia
The MERIT experiment is a proof-of-principle test of a target system for high power proton beam to be used as front-end for a neutrino factory complex or a muon collider. The experiment took data in autumn 2007 with the fast extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of about 30·1012 protons per pulse. We report results from the portion of the MERIT experiment in which separated beam pulses were delivered to a free mercury jet target with time intervals between pulses varying from 2 to 700 microseconds. The analysis is based on the responses of particle detectors placed along side and downstream of the target.
UCLA, Los Angeles, California
Instituto Superior Tecnico, Lisbon
Funding: Fundacao Calouste Gulbenkian and Fundacao para a Ciencia e Tecnologia under grants SFRH/BD/35749/2007.
The possibility of using a CO2 laser (10 micron wavelength) to drive a plasma density compression and achieve effective ion acceleration in gaseous targets (density>~ 1019cm-3) is explored. A parameter scan is performed with a set of particle in cell simulations in OSIRIS*, both in 2D and 3D, for various laser intensities, linear/circular polarization pulses, and plasma densities. Results show that, to generate the shock compression, plasma density must be increased above the critical value to account for the relativistic motion of the electrons. Under these conditions, 2-5MeV ions are observed with moderate intensity (a0=3) laser pulses. Finally, configurations to generate a shock structure are suggested, that will more efficiently accelerate the particles. This scenario is also of particular relevance to fast-ignition, inertial confinement fusion, and implications to those regimes can be obtained from numerical simulations by using the appropriate density normalization.
*R. A. Fonseca et al, LNCS 2329, III-342, Springer-Verlag, (2002)
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
J-PARC, KEK & JAEA, Ibaraki-ken
The painting injection of the 3-GeV RCS in J-PARC has been tested since May in 2008. The shift bump-magnets, which give a constant bump field in a horizontal plane during injection, comprise four magnets connected in series. However, the total integrated magnetic field over the four magnets is not zero because of the magnetic field interferences with the neighboring quadrupole magnets. So the gap of each magnet was adjusted by inserting thin insulators into the splitting plane of the side yoke so that the field integration becomes zero. The thickness was determined experimentally. The closed orbit distortion due to the field imbalances was then confirmed to be less than 1 mm. Another four paint bump-magnets are also necessary to give time-dependent fields. They are connected to their own power supplies, separately. The excitation of each magnet is calibrated by using the beam so that the created bump orbit satisfies the position and inclination at the injection point, and there are no orbit distortions outside the injection area. As for a vertical plane, a vertical paint magnet is located pi-radian upstream of the injection point to control the vertical angle of the beam.
LBNL, Berkeley, California
PPPL, Princeton, New Jersey
Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Recent changes to the NDCX beamline offer the promise of higher current compressed bunches, with correspondingly larger fluences, delivered to the target plane for ion-beam driven warm dense matter experiments. We report modeling and commissioning results of the upgraded NDCX beamline that includes a new induction bunching module with approximately twice the volt-seconds and greater tuning flexibility, combined with a longer neutralized drift compression channel.
LBNL, Berkeley, California
LLNL, Livermore, California
Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Longitudinally compressed ion beam pulses are currently employed in ion-beam based warm dense matter studies. Compression arises from an imposed time-dependent longitudinal velocity ramp followed by drift in a neutralized channel. Chromatic aberrations in the final focusing system arising from this chirp increase the attainable beam spot and reduce the effective fluence on target. We report recent work on fast correction optics that remove the time-dependent beam envelope divergence and minimizes the beam spot on target. We present models of the optical element design and predicted ion beam fluence, as well as benchtop measurements of pulsed waveforms and response.
Nagaoka University of Technology, Nagaoka, Niigata
University of the Thai Chamber of Commerce, Bangkok
TIT, Yokohama
KEK, Ibaraki
The KEK digital accelerator (KEKDA), which is an injector-free induction synchrotron capable of accelerating any ions with their possible charge state, is under construction*. This machine is an interesting device as a driver to explore a Warm Dense Matter (WDM) state. The irradiation onto a target at a small focal spot (< a few mm) with a short pulse duration (< 100 nsec) is required to create an interesting WDM state. The target temperature based on an equation-of-state fitted from SESAME table data is estimated as a function of the focal spot size and the ion number per bunch. Final focusing of an ion beam bunch extracted from KEKDA is realized through a half mini-beta system. For this purpose, the beamline has been carefully designed. Beam parameters, such as Twiss parameter, and the guiding magnet parameters will be given together with the drawing of the beamline.
*T. Adachi et al., “Modification of the KEK PS-Booster as a Digital Accelerator”, in this conference.
Transtechnik, Holzkirchen
TT-MoPS Next Generation Modular Power Supply Transtechnik designed a new generation of a high flexible high current modular Power Supply. The target was to combine the experience of the CERN-LHC-Project with the requirements of the market and some new ideas. High reliability-best performance; Strongly modular-to meet a wide range of specifications; External calibration-fully automatically calibration without moving the rack installation; Easy to repair@module level-plug and play solution for high availableness; Easy to configure-Fast notation, fast implementation, easy maintainability; High accuracy-about 100ppm current regulation; For our customer STFC Rutherford Appleton Laboratories, Transtechnik produces a modular system for output voltage up to 125 VDC (CERN LHC-Product: 18V/±40V) and a current loading between 100 A and 500 A (CERN LHC-Product:13,5kA/21kA/600A). The system consists of with a new generation of standard Power Supply modules which allow combination of the shelf Power Supply to a customised Power Supply in a flexible and comfortable way(optional Modifikation:n+1 redundancy; un/-load module for high current inductors and high voltage modules-CEBU).
Fermilab, Batavia
Muons, Inc, Batavia
Funding: Supported under DOE contract DE-AC02-07CH11359.
The Mu2e experiment has been proposed at Fermilab to measure the rate for muons to convert to electrons in the field of an atomic nucleus with unprecedented precision. This experiment uses an 8 GeV primary proton beam consisting of short (~100 nsec) bunches, separated by 1.7 μs. It is vital that out-of-bunch beam be suppressed at the level of 10-9 or less. Part of the solution to this problem involves a pair of matched dipoles operating resonantly at half the bunch rate. There will be a collimation channel between them such that beam will only be transmitted when the fields are null. The magnets will be separated by 180 degrees of phase advance such that their effects cancel for all transmitted beam. Magnet optimization considerations will be discussed, as will optical design of the beam line. Simulations of the cleaning efficiency will also be presented.
KAERI, Daejon
Funding: This work is supported by the Ministry of Education, Science and Technology of Korea.
PEFP (Proton Engineering Frontier Project) beamlines will be supplied either 20-MeV or 100-MeV proton beams from the 100-MeV proton linear accelerator for beam applications. Each proton beam will be transported to 2 beamlines for industrial purpose and 3 beamlines for the researches. Beam distribution to 3 research beam lines will be conducted sequentially by programmable AC magnet. To provide flexibility of the irradiation conditions, each beam line is designed to have specific beam parameters. We have designed the beamlines to the targets for wide or focused beams, external or in-vacuum beams, and horizontal or vertical beams. The detail design of each beamline will be reported.
KEK, Ibaraki
Thick carbon foils (>300 ug/cm2)has been used for stripping of H- ion beam at the 3GeV Rapid Cycling Synchrotron (3GeV-RCS) of J-PARC, where foils with long lifetime against high temperature >1800 °K are strongly required for efficient accelerator operations. The key parameter to the foil lifetime is foil temperature attained during irradiation. We have recently developed a new irradiation system for lifetime measurement using the KEK 650 keV Cockcroft-Walton accelerator with high current pulsed and dc H- beam, which can simulate the high-energy depositions upon foils in the RCS. During irradiation tests by this system, the temperature of foil is measured by a thermometer in a dc mode, and by using a photo-transistor in a pulsed mode. This paper describes the pulsed measurements with 5-10 mApeak, 0.1-0.5 msec duration and 25 Hz repetition.
HUST, Wuhan
Funding: Nation Nature Science Foundation of China,10435030
The design study of Cyclotron CYCHU 10MeV has been developed at Huazhong University of Science and Technology (HUST). Because of the low center frequency (100MHz) of it’s RF system, we should choose suitable directional couplers for the RF system which is supposed to be high-directivity and tight-structure. This paper analyses and synthesizes kinds of directional couplers, espacially microstrip structure, for it’s tinier volume at the low center frequency compared with stripline and branch structures. The achievement of the high-directivity with microstrip configuration is carried out by the distributed capacitor to decrease the even and odd mode phase difference. Capacitive compensation is performed by the interdigital capacitors. The proposed structure is easy to fabricate and incorporate another microwave device due to planner microstrip.
INFN-Napoli, Napoli
UCR, Riverside, California
Funding: World Wide Collaboration of a large fraction of the international agencies.
Muon ionization cooling provides the only practical solution to prepare high brilliance beams necessary for a neutrino factory or muon colliders. The muon ionization cooling experiment (MICE) is under development at the Rutherford Appleton Laboratory (UK). It comprises a dedicated beam line to generate a range of input emittance and momentum, with time-of-flight and Cherenkov detectors to ensure a pure muon beam. A first measurement of emittance is performed in the upstream magnetic spectrometer with a scintillating fiber tracker. A cooling cell will then follow, alternating energy loss in liquid hydrogen and RF acceleration. A second spectrometer identical to the first one and a particle identification system provide a measurement of the outgoing emittance. By April 2009 it is expected that the beam and first set of detectors will have been commissioned, and a first measurement of input beam emittance may be reported. Along with the plan of measurements of emittance and cooling that will follow in the second half of 2009 and in 2010.
JAEA, Ibaraki-ken
RIST, Ibaraki
NSCL, East Lansing, Michigan
Funding: The funding information for R.M. Ronningen is U.S. Department of Energy Grant Number DE-FG02-08ER41548.
The Particle and Heavy Ion Transport Code (PHITS)* has been typically used to predict radiation levels around high-energy (above 100 MeV/u) heavy-ion accelerator facilities. However, predictions of radiation levels around low-energy (around 10 MeV/u) heavy-ion facilities are also desirable, but the reliability of PHITS at low energies has not been investigated. In this work, neutron energy spectra from 10 MeV/u 12C and 16O ions incident on C and Cu targets have been calculated using the quantum molecular dynamics (QMD) model coupled to the generalized evaporation model (GEM) in PHITS. In particular, the influence of the “switching time”, defined as the time when the QMD calculation is stopped and the calculation switches to the GEM model, was studied. The calculated neutron energy spectra obtained using a value of 100 fm/c for the switching time agree well with the experimental data. We have also used PHITS to simulate an experimental study by Ohnesorge et al.**, by calculating neutron dose equivalent rates, for 3-16 MeV/u 12C, 16O and 20Ne beams incident on Fe, Ni and Cu targets. The calculated neutron dose equivalent rates agree well with the data.
*H. Iwase, K. Niita and T. Nakamura, J. Nucl. Sci. Technol. 39, 1142 (2002).
**W.F. Ohnesorge, H.M.Butler, C.B.Fulmer and S.W.Mosko, Health Physics 39, 633 (1980).
IHEP Beijing, Beijing
China Spallation Neutron Source is a high intensity beam facility planed to build in future in China. It is composed of Linac, RCS and target station. Two sets of pulsed painting bump magnets, 4 magnets in each set , will be used in CSNS RCS to create a dynamic orbit bump for injection process. The design of these 8 bump magnets has been completed. One prototype bump magnet has been assembled and tested. In this paper, the magnetic field analysis, the eddy current and thermal consideration in the end plates of the prototype bump magnet are presented, and issues of the magnet development, construction and test are discussed.
PSI, Villigen
At PSI, a new and very intensive Ultra-Cold Neutron (UCN) source based on the spallation principle will start operation at the end of 2009. From then on, two neutron spallation sources - the continuous wave SINQ and the macro-pulsed UCN source will be running concurrently at PSI. The 590 MeV, 1.2 MW proton beam will be switched towards the new spallation target for about 8 s every 800 s. This operation can be accomplished by means of a fast kicker magnet with a rise-time shorter than 1 ms. A beam dump capable of absorbing the full-intensity beam for a few milliseconds has been installed after the last bending magnet so that the kicking process and the beam diagnostic can be checked well before the UCN facility will be ready for operation. Recent tests have demonstrated the capability of switching the 1.2 MW beam with negligible losses and to center it through the beam line by using fast beam position monitors. Much longer beam pulses (up to 6 seconds) with reduced beam intensity have also been performed successfully.
ORNL, Oak Ridge, Tennessee
Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy
Latest technologies promise new control systems user interface features and greater interoperability of applications. New developments using Java and Eclipse aim to unify diverse control systems and make communication between applications seamless. Web based user interfaces can improve portability and remote access. Modern programming tool improve efficiency, support testing and facilitate shared code. This talk will discuss new developments aimed at improving control system interfaces and their development environment.
Cosylab, Ljubljana
Accelerators are designed to be in operation for several decades, and frequently even their construction alone takes a decade or more. Given the rapid rate of obsolescence of information technologies, it becomes a challenge how to choose the technologies that would stand the test of time, or at least make long-term support manageable. In this article, we focus on middleware: the glue that keeps inherently heterogeneous control system platforms able to interoperate with each another. Modern and less-modern middlewares, such as Internet Communication Environment (ICE), Common Object Request Broker Architecture (CORBA), Microsoft Windows Communications Foundation (WCF) are presented, and contrasted with more domain-specific middleware, such as the Experimental Physics and Industrial Control System (EPICS). We argue that whichever middleware technology is used, it is advisable to abstract it with simple, domain-specific APIs, whose implementation can change as the evolving performance requirements push the initial middleware choice beyond its limits of applicability.
BESSY GmbH, Berlin
HZB, Berlin
The Metrology Light Source (MLS) is in user operation since April 2008 working at energies ranging from {10}5 MeV up to 630 MeV, operating currents from a single electron up to 200 mA and different values for the momentum compaction factor. In parallel to machine commissioning, an automated finite state machine has been developed. This code knows, controls and coordinates a broad manifold of machine states and meanwhile has been evolved to an automated operator acting by itself on demand of a few high level commands. Actions range from plain device I/O to complex transactions including filesystem operations and multiple device I/O. The aim is to always keep machine and control system in a well-defined state. We describe the program and report on the experience with the automated operation using this application.
ORNL, Oak Ridge, Tennessee
Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
The Spallation Neutron Source (SNS) has operated at beam powers over 650 kW, and is expecting to approach 1 MW operation by the summer of 2009. Challenges in operating a proton accelerator at these power levels is reducing the uncontrolled beam loss to levels approaching 10-6/meter, and ensuring machine protection. Experience with beam tuning and safely handling the high power will be presented. Also the progress in beam loss reduction over the course of the power ramp-up will be reviewed.
On behalf of the SNS Team
STFC/RAL, Chilton, Didcot, Oxon
Exeter University, Exeter, Devon
Gericke LTD, Ashton-under-Lyne
This paper describes the potential of fluidised powdered material for use as a particle production target in high power particle accelerator based facilities. In such facilities a multi-MW proton beam is required to interact with a dense target material in order to produce sub-atomic particles, e.g. neutrons for a neutron source or pions for a so-called conventional neutrino beam, a neutrino factory or a muon collider. Experience indicates that thermal transport, shock wave and radiation damage will limit the efficiency and reliability of facilities utilising solid targets at around 1 MW beam power. Consequently liquid mercury has been adopted as the target technology for the latest neutron facilities SNS and J-SNS at ORNL and Tokai respectively, and is the baseline for a neutrino factory and muon collider. However mercury introduces new problems such as Cavitation Damage Erosion. This paper discusses how a fluidised powder target may combine many of the advantages of a liquid metal with those of a solid, and describes an experimental programme at RAL currently underway to implement this technology.
Fermilab, Batavia
CERN, Geneva
IHEP Protvino, Protvino, Moscow Region
INFN-Ferrara, Ferrara
PNPI, Gatchina, Leningrad District
BNL, Upton, Long Island, New York
Università dell'Insubria & INFN Milano Bicocca, Como
Enrico Fermi Institute, University of Chicago, Chicago, Illinois
Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Bent-crystal channeling is a technique with a potential to increase the beam-halo collimation efficiency at high-energy colliders. First measurements at the Tevatron in 2005 have shown that using a 5-mm silicon crystal to deflect the proton beam halo onto a secondary collimator improves the system performance by reducing the machine impedance, beam losses in the collider detectors and irradiation of the superconducting magnets, all in agreement with simulations. Recent results, obtained with substantially improved goniometer and enhanced beam diagnostics, are reported showing channeling collimation of the ~1-TeV circulating proton beam halo at the Tevatron collider. Comprehensive results of computer modeling are presented which allow further developments of the T-980 experiment towards a robust system compatible with requirements to high-efficient collimation at the Tevatron and LHC hadron colliders.
JLAB, Newport News, Virginia
Helium refrigerators are of keen interest to present and future particle physics programs utilizing superconducting magnet or radio frequency (RF) technology. They typically utilize helium refrigeration at and below 4.5-Kelvin (K) temperatures and are very energy intensive. After an overview of the quality of energy, basic processes used for cryogenics, the Carnot step (as defined by the author) and cycle design theory, the concept of overall process optimization is presented. In particular the question of ‘what is an optimum system’ will be discussed. In this regard, the Ganni cycle and floating pressure control philosophy will be examined with respect to a more traditional approach as a solution to an optimum system for new designs and existing systems.
ORNL, Oak Ridge, Tennessee
Funding: SNS is managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC05-00OR22725
The SNS Ring has now been operating for about 2.5 years, and our march continues to increase the beam power to the design value of 1.4 MW. The Ring is a loss-limited machine, and in general the radioactivation levels are good, but there are some unanticipated hot spots that we are working to relieve. Beam optics functions have been measured using the model independent and orbit response matrix methods, and our results will be compared to the ideal model. High-intensity beam profiles measurements show space-charge effects, and these will be compared to model calculations. We will also discuss the status of equipment upgrades that are now in progress in the high-energy beam transport momentum dump, the injection-dump beam line, and in the ring-to-target beam line.
LAL, Orsay
INFN/LNL, Legnaro (PD)
LAL-Orsay is developing an important effort on R&D studies on RF power couplers. One of the most critical components of those devices is the ceramic RF window that allows the power flux to be injected in the coaxial line. The presence of a dielectric window on a high power RF line has a strong influence on the multipactor phenomena. To reduce this effect, the decrease the secondary emission yield (SEY)of the ceramic window is needed. Due to its low SEY coefficient, TiN coating is used for this goal. In this framework, a TiN sputtering bench has been developed in LAL. The reactive sputtering of TiN needs the optimisation of gas flow parameters and electrical one, to obtain stoechiometric deposit. XRD analysis was performed to control the film composition and stoechiometry. Measurements point out how the Nitrogen vacancy on the film can be controlled acting on the N2 flow. In addition, the coating thickness must be optimized so that the TiN coating effectively reduces the SEY coefficient but does not cause excessive heating, due to ohmic loss. For this purposes, multipactor level breakdown and resistance measurements were done for different deposit thickness.
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
Cockcroft Institute, Lancaster University, Lancaster
The ILC crab cavities require very tight phase control in order to operate within the ILC parameters. In order to verify that the phase control system met the design tolerances, two single-cell niobium 3.9GHz superconducting dipole-mode cavities were tested in a liquid helium cryostat. The preparation of the cavities, design of the testing apparatus and performance of the phase control system are described in this paper.
ORNL, Oak Ridge, Tennessee
Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.
Four ferrite loaded resonant radio frequency (RF) cavity structures and one resistive wall current monitor (WCM) located in the South leg of the Spallation Neutron Source (SNS) accumulator ring provide a 250 ns beam extraction gap. Three ring RF cavities operate at the fundamental accumulator ring revolution frequency (~ 1.05 MHz) to bunch the beam while the fourth cavity operates at the second harmonic (~ 2.10 MHz) to suppress the peak beam current. The SNS ring low-level RF (LLRF) control system utilizes dynamic cavity tuning and proportional, integral, and derivative (PID) feedback control to regulate the amplitude and phase of the fields in the ring RF cavities. In April 2009 the SNS accelerator delivered 835 kW of beam power (928 MeV, 60 Hz, 15 uC/pulse) to the target during a neutron production run. This paper discusses operation and performance of the SNS ring LLRF system with high intensity beam loading.
FZJ, Jülich
IKP, Mainz
ELSA, Bonn
BNL, Upton, Long Island, New York
DELTA, Dortmund
The feasibility of a polarized Electron-Nucleon Collider (ENC) with a center-of-mass energy up to 13.5 GeV for luminosities above 2·1032 cm-2 s-1 is presently under consideration. The proposed concept integrates the planned 14 GeV High-Energy Storage Ring (HESR) for protons/deuterons and an additional 3 GeV electron ring. Calculations of cooled beam equilibria including intra-beam scattering and beam-beam interaction have been performed utilizing the BetaCool code. A special design of the interaction region is required to realize back-to-back operation of the HESR storage ring together with the elaborated collider mode. For polarized proton/deuteron beams additional equipment has to be implemented in several machines of the acceleration chain and the HESR to preserve the beam’s polarization. A scheme for polarized electrons is still under investigation. In this presentation the required modifications and extensions of the HESR accelerator facility at the future International Facility for Antiproton and Ion Research (FAIR) are discussed and the proposed concept is presented.
ORNL, Oak Ridge, Tennessee
CERN, Geneva
BNL, Upton, Long Island, New York
PU, Princeton, New Jersey
Funding: U.S. Department of Energy contract DE-AC05-00OR22725
Operation of a mercury jet delivery system is presented. The delivery system is part of the Mercury Intense Target (MERIT) Experiment, a proof-of-principle experiment conducted at CERN in 2007 which demonstrated the feasibility of using an unconstrained jet of mercury as a target for a future Neutrino Factory or Muon Collider. The Hg system was designed to produce a 1-cm-diameter, 20 m/s Hg jet inside a high-field (15 Tesla), 15-cm-bore solenoid magnet. A high-speed optical diagnostic system allowed observation of the interaction of the jet with both 14- and 24-GeV proton beams. Performance of the Hg system during the in-beam experiment will be presented.
UCLA, Los Angeles, California
BNL, Upton, Long Island, New York
Funding: DOE
A study of target parameters for a high-intensity, liquid mercury jet target system for a neutrino factory or muon collider is presented. Using the MARS code, we simulate particle production initiated by incoming protons with kinetic energies between 2 and 100 GeV. For each proton beam energy, we optimize the geometric parameters of the target: the mercury jet radius, the incoming proton beam angle, and the crossing angle between the mercury jet and the proton beam. The number of muons surviving through an ionization cooling channel is determined as a function of the proton beam energy
KEK, Ibaraki
The e+/e- injector LINAC in KEK usually successively injects into four rings, which are Low Energy Ring (LER) of KEKB (3.5GeV/e+), High Energy Ring (HER) of KEKB (8.0GeV/e-), Photon Factory (PF) (2.5GeV/e-) and Advanced Ring for pulse X-rays (PF-AR) (3.0GeV/e-). While LINAC continuously injects into LER and HER alternatively every about five minutes, keeping both of KEKB rings almost their full operating currents. It takes about one minute to switch beam mode of LINAC. PF and PF-AR are injected a few times in a day. Time for PF or PF-AR including mode-switch had taken about 20 minutes for each other. For PF injection, the switching time was shortened in 2005 and the occupancy time is about 5 minutes. In 2008, we succeeded to make the switching time shorter, 2 seconds for HER/LER, and Pulse-to-pulse alternatively injection for PF/HER using an event system. Especially for KEKB, the short switching time is contributed to provide high currents and to improve luminosity at which beam lives are too short to keep the high currents. In 2009, we have a plan to inject also for LER/HER pulse-to-pulse alternatively.
BNL, Upton, Long Island, New York
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
ORNL, Oak Ridge, Tennessee
CERN, Geneva
PU, Princeton, New Jersey
Fermilab, Batavia
We report on the analysis of data collected from the optical diagnostics of the MERIT experiment which was run at CERN in the fall of 2007. The breakup of the free mercury jet resulting from the impact of intense proton beams from the CERN PS within a magnetic field environment is described.
Bruce Technologies Inc., North Billerica, MA
D-Pace, Nelson, British Columbia
Many of today’s PET cyclotrons are delivered from the factory for fully-automated “black box” operation in a hospital-based clinical program. Simplicity and ease of operation by non-specialists is desired, and this is achieved in-part through relatively low current targets bolted directly to the PET cyclotron’s main vacuum tank. However, commercial-scale production of short-lived radiopharmaceuticals is becoming increasingly prevalent where substantially higher-current target operation* requiring greater optimization of beam parameters through compact external beamlines**,*** is necessary to meet ever-more demanding production schedules and delivery commitments. This paper describes a system which incorporates the highest current and highest power PET water targets and a short well-instrumented beamline for beam centring/focusing and maximum productivity.
*M. Stokely et al, WTTC11, Cambridge, 2006, p.{10}2.
**M.P. Dehnel et al, NIM B 261, 2007, p. 809.
***J.E. Theroux et al, CYC2007, Giardini Naxos, Italy, 2007, p. 361.
ORNL, Oak Ridge, Tennessee
Funding: SNS is managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC05-00OR22725
As the SNS beam power is increased, the collimator systems are becoming correspondingly more important. The High Energy Beam Transport (HEBT) transverse collimators are now routinely used during neutron production. We are in the process of redesigning the HEBT momentum collimation system due to problems with gas production from radiolysis. The Ring collimators are designed for two-stage operation but to date they are mainly used in one-stage mode. In this paper we will discuss the status, the operational performance, and upgrades to the collimation systems.
ORNL, Oak Ridge, Tennessee
Funding: *SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy
The combined time required for diffusion release from target materials and effusive-flow of short-lived ion species must be minimized at ISOL based radioactive ion beam (RIB) facilities. Computational simulation studies with state-of-the-art codes offer cost effective means for designing targets with optimized diffusion release properties and vapor transport systems with short path lengths, as required for such applications. To demonstrate the power of the technique for designing optimum thickness targets, analytic solutions to the diffusion equation are compared with those obtained from a finite-difference code for radioactive particle release from simple geometries. The viability of the Monte Carlo technique as a practical means for optimally designing vapor transport systems is demonstrated by simulating the effusive-flow of neutral particles through several complex vapor transport systems. Important issues which affect the yield rates of short-lived species generated in high power ISOL targets are also discussed.
STFC/RAL, Chilton, Didcot, Oxon
Exeter University, Exeter, Devon
Gericke LTD, Ashton-under-Lyne
This paper proposes a technology based on fluidized powder which could be employed as a high power target (and beam dump), for example in a future Neutrino Factory or Muon Collider. A fluidized powder target is believed to bring together some advantages of both the solid and liquid phase whilst avoiding some of their drawbacks. The current Neutrino Factory and Muon Collider proposals require the use of a high Z target material withstanding beam ionisation heating of around 1 MW. The article proposes to use a dense tungsten powder jet as an alternative to the baseline open mercury jet for interaction with the proton beam inside the high field capture solenoid. The preliminary experimental results on the production and on the characteristics of a dense horizontal tungsten powder jet are presented. The morphology of the jet is analysed and presented as a function of the driving parameters (e.g. pneumatic supply pressure, boundary conditions of the jet, etc.). A test rig was developed to investigate the reliability of lean and dense phase pneumatic conveying of tungsten powder and the results of such experiments are discussed in the paper.
STFC/RAL, Chilton, Didcot, Oxon
Kyoto University, Kyoto
KEK, Ibaraki
Funding: Science and Technology Facilities Council
The T2K experiment will utilise the highest pulsed power proton beam ever built to generate an intense beam of neutrinos. This uses the conventional technique of colliding the 0.75 MW 30 GeV proton beam with a graphite target and using a magnetic horn system to collect pions of one charge and focus them into a decay volume where the neutrino beam is produced. The target is a two interaction length (900 mm long) graphite target supported directly within the bore of the first magnetic horn which generates the required field with a pulsed current of 300 kA. This paper describes the design and development of the target system required to meet the demanding requirements of the T2K facility. Challenges include radiation damage, shock waves resulting from a 100 K temperature rise in the graphite material during each beam spill, design and optimisation of the helium coolant flow, and integration with the pulsed magnetic horn. Conceptual and detailed engineering studies were required to develop a target system that could satisfy these requirements and could also be replaced remotely in the event of a target failure.
STFC/RAL, Chilton, Didcot, Oxon
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
Birmingham University, Birmingham
Spoilers in the ILC Beam Delivery System are required to survive without failure a minimum of 1-2 direct impacts of 250 GeV-500 GeV bunch of electrons or positrons, in addition to maintaining low geometric and resistive wall wake fields. The likelihood of spoiler survival was determined using finite element models of thermal and mechanical properties of the spoilers, with realistic patterns of energy deposition as input. The second phase of an experiment to calibrate the finite element models using electron beam data will be performed in the ATF2 extraction line, by subjecting a small sample of Ti-6Al-4V to bunches of electrons. The displacement of the surface will be measured with a Velocity Interferometer System of Any Reflector (VISAR). This paper shows the project plan as well as results of the simulations and expected readout from the VISAR.
STFC/RAL, Chilton, Didcot, Oxon
KEK, Ibaraki
The target station of the T2K neutrino facility requires a beam window to separate the target chamber, containing helium at atmospheric pressure, from the secondary beam line, which is maintained at ultra high vacuum. In addition to withstanding this differential pressure, the window must survive induced stresses due to intense heating resulting from interaction with a 0.75 MW pulsed proton beam. The design consists of a hemispherical double window with forced convection helium cooling in the volume enclosed, manufactured from titanium alloy. Preliminary analysis suggested that 'shock' waves induced by the pulsed nature of the beam will form the dominant mode of stress. The finite element software ANSYS Mechanical (V10) has been used to simulate the effect of beam impingement on a variety of window thicknesses in an attempt to find the optimum geometry. Results have shown that through thickness stress waves can be amplified if successive bunches arrive in phase with the waves generated by previous bunches. Therefore, thickness has been shown to be a critical variable in determining the window’s resistance to induced thermal shock.
Sheffield University, Sheffield
University of Warwick, Coventry
STFC/RAL/ISIS, Chilton, Didcot, Oxon
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
Funding: Science and Technology Facilities Council (United Kingdom)
The UK programme of high power target developments for a Neutrino Factory is centred on the study of high-Z materials (tungsten, tantalum). A description of lifetime shock tests on candidate materials is given as a part of the research into a solid target solution. A fast high current pulse is applied to a thin wire of the sample material and the lifetime measured from the number of pulses before failure. These measurements are made at temperatures up to ~2000 K. The stress on the wire is calculated using the LS-DYNA code and compared to the stress expected in the real Neutrino Factory target. It has been found that tantalum is too weak at these temperatures but a tungsten wire has reached over 26 million pulses (equivalent to more than ten years of operation at the Neutrino Factory). Measurements of the surface velocity of the wire using a laser interferometry system (VISAR) are in progress, which, combined with LS-DYNA modelling, will allow the evaluation of the constitutive equations of the material. An account is given of the optimisation of secondary pion production and capture in a Neutrino Factory and of the latest solid target engineering ideas.
Sheffield University, Sheffield
The MICE experiment requires a beam of low energy muons to test muon cooling. This beam is derived parasitically from the ISIS accelerator at the Rutherford Appleton Laboratory. A novel target mechanism has been developed which allows the insertion of a small titanium target into the proton beam on demand, for the final couple of milliseconds before extraction. The first operational linear drive was installed onto ISIS in January of 2008. Since then, it has operated for over 100,000 actuations. Studies have been performed of particle production and collection by the MICE beam-line, as well as verification of the reliability of the target drive itself. The target data acquisition system records not only the position of the target throughout the ISIS acceleration cycle, but also the outputs from beam loss monitors placed around the synchrotron. Data will be presented showing the stability of the target’s motion and the correlation of beam loss and particle production with the timing and depth of the target’s intersection with the circulating beam.
Sheffield University, Sheffield
The MICE Experiment requires a beam of low energy muons to demonstrate muon cooling. This beam is derived parasitically from the ISIS accelerator. A novel target mechanism has been developed that inserts a small titanium target into the proton beam on demand. The target remains outside the beam envelope during acceleration and then overtakes the shrinking beam envelope to enter the proton beam during the last 2 ms before beam extraction. The technical specifications for the target mechanism are demanding, requiring large accelerations and precise and reproducible location of the target each cycle. The mechanism operates in a high radiation environment, and the moving parts are compatible with the stringent requirements of the accelerator’s vacuum system. This paper will describe the design of the MICE target and how it is able to achieve its required acceleration whilst still meeting all of the necessary requirements for operation within the ISIS vacuum. The first operational linear electromagnetic drive was installed onto ISIS in January 2008 and has since been operated for over one hundred thousand actuations.
Imperial College of Science and Technology, Department of Physics, London
Fermilab, Batavia
The International Design Study for the Neutrino Factory (IDS-NF), which is being carried out by personnel from the Americas, Asia, and Europe, has been established by the Neutrino Factory community to deliver a Reference Design Report for the facility by 2012*. The baseline design, developed from that defined in the ISS**, will provide 1021 muon decays per year from 25GeV stored muon beams. The facility will serve two neutrino detectors; one situated at source-detector distance of between 3000-5000km, the second at 7000-8000km. Muon storage rings have also been proposed as the basis of a multi-TeV lepton-antilepton Muon Collider. The R&D required to deliver the Neutrino Factory and that required to realise the Muon Collider have many synergies including: the pion-production target; ionisation cooling; rapid acceleration of large emittance beams; and the provision of high-gradient accelerating cavities that operate in high magnetic fields. The conceptual design of the accelerator facility for the Neutrino Factory and the relation of the IDS-NF to the EUROnu Design Study will be described***.
*The decision point identified by the Strategy Group of the CERN Council.
**The International Scoping Study for a future Neutrino Factory and super-beam facility.
***Submitted on behalf of the IDS-NF.
LBNL, Berkeley, California
Funding: US Department of Energy
Staging Laser Plasma Accelerators (LPA), which is necessary in order to substantially increase the electron beam energy, requires incoupling additional laser beams into accelerating stages. To preserve high accelerating gradient of LPA, it is imperative to minimize the distance that is needed for laser incoupling. Using a conventional mirror with PW-class lasers will require the incoupling distance to be as long as tens of meters due to limitations imposed by laser induced damage of the optic. In this presentation we will describe a new approach for the laser incoupling that is based on planar water jet plasma mirror. The plasma mirror can operate as close as few cm to the focus of the laser thus minimizing the coupling distance. Using a water jet instead of a solid target avoids mechanical scanning of the target surface as well as contamination of the vacuum by laser breakdown debris. Experimental results showing performance of the water jet plasma mirror will be presented and progress in staging experiments will be discussed
ORNL, Oak Ridge, Tennessee
There are many planned or nascent particle-accelerator-based projects world-wide. Often these are large and complex projects that can benefit from strong project management. Following the premise that it is better to learn from the community’s successes rather than its mistakes, this talk will draw on successful experiences from the Oak Ridge SNS project in elaborating strategies and techniques for successful project management.
LBNL, Berkeley, California
LLNL, Livermore, California
PPPL, Princeton, New Jersey
Voss Scientific, Albuquerque, New Mexico
The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the warm dense matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has been demonstrated in the Neutralized Drift Compression Experiment (NDCX) with controlled ramps and forced neutralization. Using an injected 30 mA K+ ion beam with initial kinetic energy 0.3 MeV, axial compression leading to ~100X current amplification and simultaneous radial focusing to a few mm have led to encouraging energy deposition approaching the intensities required for eV-range target heating experiments. We discuss the status of several improvements to NDCX to reach the necessary higher beam intensities, including:
- greater axial compression via a longer velocity ramp;
- beam steering dipoles to mitigate aberrations in the bunching module;
- time-dependent focusing elements to correct considerable chromatic aberrations; and
- plasma injection improvements to establish a plasma density always greater than the beam density, expected to be >1013 cm-3.
NIRS, Chiba-shi
AEC, Chiba
Based on more than ten years of experience of the carbon cancer therapy with HIMAC, we have proposed a new treatment facility for the further development of the therapy with HIMAC. This facility will consist of three treatment rooms: two rooms equipped with horizontal and vertical beam-delivery systems and one room with a rotating gantry. For the beam-delivery system of the new treatment facility, a 3D hybrid raster-scanning method with gated irradiation with patient’s respiration has been proposed. A R&D study has been carried out toward the practical use of the proposed method, although this method was verified by a simulation study. In the R&D study, we have improved the beam control of the size, the position and the time structure for the proposed scanning method with the irradiation gated with patient’s respiration. Further, owing to the intensity upgrade of the synchrotron, we can successfully extend the flattop duration, which can complete one fractional irradiation with one operation period and can increase the treatment efficiency of the gated irradiation. We will report the recent progress on HIMAC for carbon therapy.
KURRI, Osaka
University of Fukui, Faculty of Engineering, Fukui
Accelerator based neutron source with an internal target (ERIT-emittance recovery internal target) placed into the proton storage ring has been developed. In this scheme, the beam and energy degradation caused by the target are cured by ionization cooling and the thermal and epi-thermal neutron flux of more than 1x109 n/cm2/sec can be obtained. The experimental results will be given in the conference.
LULI, Palaiseau
INRS-EMT, Varennes (Québec)
Osaka University, Graduate School of Engineering, Osaka
Beam optimization of laser-accelerated protons is a crucial point for the development of applications in various areas. Several directions need to be pursued, namely (i) optimization of the high-energy end of the spectrum e.g. for dense plasma radiography, and (ii) enhancement of laser-to-protons conversion efficiency and reduction of divergence e.g. for fast ignition. We will present recent experimental results and simulations on these topics. We will show that high-energy protons in the TNSA regime could be enhanced using low-density plasmas [2] or reduced mass solid targets [3]. The laser-to-protons conversion efficiency is equally sensitive to laser and target parameters and can be increased using ultra-thin targets [4] or reduced mass solid targets [3]. In addition, we will present some results in exploring radiation-pressure acceleration of ions using circularly polarized laser pulses.
[3] S. Buffechoux et al., “Enhanced laser acceleration of protons from reduced mass targets”, in preparation
[4] P. Antici, J. Fuchs et al., IEEE Trans. On Plasma Sci. 36, 1817 - 1820 (2008).
Diamond, Oxfordshire
The study of nonlinear effects in storage rings requires massively parallel particle tracking over a range of initial conditions. Stream processing architectures trade cache size for greatly increased floating point throughput in the case of regular memory access patterns. The symplectic integrator of Tracy-II* has been implemented in CUDA** on the nVidia stream processor and used to calculate dynamic apertures and frequency maps for the Diamond low-alpha lattice. To facilitate integration with existing workflows the the lattice description of Accelerator Toolbox*** is re-used. The new code is demonstrated to achieve a two orders of magnitude increase in tracking speed over a single CPU core and benchmarks of the performance and accuracy against other codes are presented.
*J. Bengtsson, Tracy-2 User's Manual, Feb 1997.
**NVIDIA, NVIDIA_CUDA_Programming_Guide_1.1.pdf
***A. Terebilo - ACCELERATOR MODELING WITH MATLAB ACCELERATOR TOOLBOX, PAC 2001
ENEA C.R. Frascati, Frascati (Roma)
In this paper the Fast Multipole Approximation is described with regard to the problem of modelling self fields effects in low emittance, high brightness electron beams of interest for future accelerators and light sources. This well established technique is known to scale as O(N) or O(N log N) (depending on details of the implementation) with the number of particles involved in the simulation. Performances and results as a standalone technique or as a method for for fast calculation of boundary conditions together with other approaches based on PDEs are discussed, along with details of a parallel implementation in the tracking code Tredi.
IIT, Chicago, Illinois
Illinois Institute of Technology, Chicago, Illinois
Fermilab, Batavia
Muons, Inc, Batavia
Funding: Supported in part by USDOE Contract DE-FG02-6ER86281
The study of Muon beam optics is crucial for future Neutrino Factory and Muon Collider facilities. At present, the GEANT4-based simulation tools for Muon beam tracking such as G4beamline and G4MICE are based on single particle tracking without collective effects taken into account. However, it is known that collective effects such as space charge and wakefields for muons (in matters or vacuum) are not ignorable. As the first step, space charge computation has been implemented into muon tracking. The basic algorithm is particle to particle interactions through retarded electro-magnetic fields. The momentum impulse by collective effects is imposed on every particle at each collective step, and the G4beamline main code is used for tracking. Comparisons to LANL Parmela are illustrated and analyzed. Optimizations of the algorithm are also underway to gain less computing time and more accuracy. Moreover, the idea of enhancing ionization cooling efficiency by utilizing the collective effect due to polarized charges in matter appears to be possible, and the preliminary estimation has been done.
Muons, Inc, Batavia
Illinois Institute of Technology, Chicago, Illinois
IIT, Chicago, Illinois
Funding: Supported in part by USDOE STTR Grant DE-FG02-06ER86281
Most computer programs that calculate the trajectories of particles in accelerators assume that the particles travel in an evacuated chamber. The development of muon beams, which are needed for muon colliders and neutrino factories and are usually required to pass through matter, is limited by the lack of user-friendly numerical simulation codes that accurately calculate scattering and energy loss in matter. Geant4 is an internationally supported tracking toolkit that was developed to simulate particle interactions in large detectors for high energy physics experiments, and includes most of what is known about the interactions of particles and matter. Geant4 has been partially adapted in a program called G4beamline to develop muon beam line designs. The program is now being developed and debugged by a larger number of accelerator physicists studying muon cooling channel designs and other applications. Space-charge effects and muon polarization are new features that are being implemented.
BNL, Upton, Long Island, New York
Fermilab, Batavia
Funding: Work performed under the auspices of the US Department of Energy
SiO2 quartz fibers of the LHC ATLAS 0-degree calorimeter (ZDC) anticipated to experience integrated doses of a few Grad at their closest position were exposed to 200 MeV protons and neutrons at the BNL Linac. Specifically, 1mm- and 2mm- diameter quartz (GE 124) rods were exposed to direct 200 MeV protons during the first phase of exposure leading to peak integrated dose of ~28 Grad. Exposure to a primarily neutron flux of 1mm-diameter SiO2 fibers was also achieved with a special neutron source arrangement. In a post-irradiation analysis the quartz fiber transmittance was evaluated as a function of the absorbed dose. Dramatic degradation of the transmittance property was observed with increased radiation damage. In addition, detailed evaluation of the fibers under the microscope revealed interesting micro-structural damage features and irradiation-induced defects. This paper presents the results of the irradiation damage study.
BNL, Upton, Long Island, New York
Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The proton polarization measurements in AGS and RHIC are based on proton-carbon and proton-proton elastic scattering in the Coulomb Nuclear Interference region. Polarimeter operation in the scanning mode gives polarization profiles and beam intensity profile measurements. This polarimeter is an ideal wire-scanner due to: extremely good signal/noise ratio and high counting rate, which allows accurate bunch by bunch emittance measurements during 100 ms time of the beam crossing. The measurements of the beam emittance in both vertical and horizontal planes will be possible after polarimeter upgrade for the 2009 polarized run. Two new vacuum chambers and two target motion mechanisms and detectors assembly will be installed in each ring. One polarimeter can be used for the vertical polarization and intensity profile measurements and the second can be used for the horizontal profile measurements. The absolute accuracy limitations and cross-calibration of different techniques will be also discussed.
DPNC, Genève
The MICE experiment aims at demonstrating that the performances of the muon ionization technique are compatible with the requirements of the neutrino factory and the muon collider. The experiment is running at the Rutherford-Appleton Laboratory in the UK using the ISIS proton beam on a dynamic target as a muon source. Brand new target system and muon beam line have been designed, built and installed during the last two years. On the other hand, particle identification detectors needed for the experiment have also been installed and commissioned. This presentation describes how we made use of Time of Flight detectors, aerogel Cherenkov counters and electro-magnetic calorimeter sensors to characterize the content of the MICE beam between 100 and 480 MeV/c.
JAI, Egham, Surrey
CERN, Geneva
The diagnostics of a 6D phase space distribution is a crucial and a challenging task, which is required for modern and future installations such as light sources or linear colliders, like CLIC. The longitudinal profile is one of the parameters which needs to be monitored. A setup for the investigation of coherent diffraction radiation from a conducting screen as a tool for non-invasive longitudinal electron beam profile diagnostics has been designed and installed in the CRM line of the CLIC Test Facility (CTF3) at CERN. This setup also allows the measurements of Coherent Synchrotron Radiation from the last bending magnet. In this report we present the status of the experiment and show some preliminary results on coherent synchrotron radiation and coherent diffraction radiation studies. The plans for interferometric measurements of coherent radiation are also presented.
LANL, Los Alamos, New Mexico
NSTec, Los Alamos, New Mexico
Funding: Work supported by the United States Department of Energy, DOE contract Number: W-7405-ENG-36
Accurate and reliable beam position measurements are required to commission and operate the DARHT II Accelerator. The Beam Position Monitor (BPM) system developed for use on the DARHT II accelerator consists of 31 electro-magnetic detector assemblies, a computer network based data acquisition system, and custom analysis software. During an accelerator “shot”, each BPM uses arrays of b-dot detectors to intercept the electron beam’s changing magnetic field. Post shot analysis of the BPM data provides the beam current and position information used for steering and tuning subsequent shots. This paper will analyze the performance of the BPM system, now that several thousand beam shots have been achieved.
Muons, Inc, Batavia
Northern Illinois University, DeKalb, Illinois
Funding: Supported in part by the Illinois Department of Commerce and Economic Opportunity
The multi-pixel photon counter (MPPC), or Geiger-mode avalanche photo-diode (GM-APD), also known as silicon photomultiplier (SiPM) is of great interest as a photon detector for high-energy physics scintillation counters, and other applications. In this paper we discuss some of the performance characteristics of MPPCs, and several applications, namely for muon cooling experiments, rare muon decay modes, and collider detectors. In addition we will discuss advances in signal processing electronics for MPPCs, which further enhance their use for large-scale applications.
ANL, Argonne
Northern Illinois University, DeKalb, Illinois
An exotic beam facility for the production of rare isotopes such as the Facility for Rare Isotope Beams (FRIB) at Michigan State University will require a high resolution fragment separator to separate isotopes of varying mass and charge. The goal of the fragment separator is to produce a high-purity beam of one rare isotope. Sources of contamination in a beam such as this are isotopes with a similar magnetic rigidity to the separated isotope and those which are produced by fragmentation in the energy degrader. This can be particularly detrimental when a contaminating isotope has a large cross section. Here we investigate beam purity as a function of the separated isotope and the type of fragment separator setup used, i.e. one stage, two stage, or one stage with gas cell branch.
CERN, Geneva
The LHC phase II collimation project requires beam shock and impact tests of materials used for beam intercepting devices. Similar tests are also of great interest for other accelerator components such as beam entrance/exit windows and protection devices. For this purpose a dedicated High Radiation Material test facility (HiRadMat) is under study. This facility may be installed at CERN at the location of a former beam line. This paper describes the associated beam line which is foreseen to deliver a 450 GeV proton beam from SPS with an intensity of up to 3·1013 protons per shot. Different beam line designs will be compared and the choice of the beam steering and diagnostic elements will be discussed, as well as operational issues.
Imperial College of Science and Technology, Department of Physics, London
The Muon Ionisation Cooling Experiment (MICE) at RAL will be the first apparatus to study muon cooling at high precision. Muons are produced along a transport beamline in a super-conducting solenoid via pion decay. The final beam emittance is generated by tuning the quadrupoles for beam size matching. The beam angular divergence is matched in a variable-thickness diffuser, which is a re-entrant mechanism inside the first solenoid, automatically changeable in few minutes from 0 to 4X0. The initial normalized emittance of the beam (few mm rad) will be inflated up to 10 mm rad in order to cover the (eN,P) matrix required by the experiment. Details of beamline tuning are presented.
JAEA/TARRI, Gunma-ken
CNS, Saitama
It is possible to fold the tails of the transverse beam profile into the inside, or even to uniformize the beam distribution in the properly-designed nonlinear beam transport system. A two-dimensionally uniform beam profile was formed using sextupole and octupole magnets at the azimuthally-varying-field cyclotron facility of Japan Atomic Energy Agency. Such a uniform beam exhibits a unique feature in the viewpoint of a uniform irradiation system; as compared to the raster scanning system, it enables us to perform uniform irradiation over the whole area of a large sample at a constant particle fluence rate. For the application of materials sciences, uniformization of heavy-ion beams as well as protons has been performed. In order to reduce undesirable beam halos at the target, tail-folding of the spot beam is also planed using the nonlinear focusing method.
PSI, Villigen
The Paul Scherrer Institute (PSI) operates a high power proton accelerator for the research projects in physical and medical sciences. Currently, a proton beam current of 2mA with a beam power of 1.2MW is routinely used. In the future, the ring cyclotron with new cavities will make a proton beam current of 3mA possible. The enhanced beam power will generate higher thermal and mechanical loads to different accelerator components. In this paper, a simulation based study of a new current monitor designed to sustain the 3mA beam operation is presented. The monitor is located behind the second graphite target and exposed to scattered particles and their secondaries. The thermal energy deposition in the current monitor has been calculated by the Monte-Carlo particle transport code MARS. The calculated power source has been used for the the coupled flow, heat and radiation simulations, for the prediction of the operating temperature. The effect of the newly introduced water cooling system and the surface blackening has been analyzed by using CFX. The thermal properties of the monitor system have been measured by laboratory experiments, and a simulation validation study is presented.
PSI, Villigen
With increasing beam powers and current densities in current neutron spallation sources one approaches materials' limits. The importance of near-target beam monitoring rises accordingly. At the Paul Scherrer Institute (PSI), the liquid metal target of MEGAPIE set especially stringent requirements for the reliable interruption of the proton beam in case of an anomaly in the incident current density distribution. A completely novel device called VIMOS based on the optical monitoring of a glowing mesh has been devised. By now, the system has been operating successfully for five years. Starting from the initial goal of reliably detecting beam anomalies in a timely manner the scope of the system has been extended to serve as a standard device for beam monitoring and fine tuning of the settings of the beam transport lines. In parallel to the expansion of the use of VIMOS over time, requirements for improving the maintainability of the system while also reducing concurrent cost have become more urgent. A summary of the operational experience of VIMOS will be reported as well as steps taken in order to deliver more quantitative data on the beam profile in the future.
RCNS, Sendai
KEK, Ibaraki
Tohoku University, School of Scinece, Sendai
We have designed a beam orbit tilt monitor for stabilizing a beam orbit in ATF2. Once we can measure a beam orbit tilt angle with high precision at one point, we can relate this data with the beam position profile at the focal point. This monitor is composed of a single rectangular cavity and waveguides to extract the signal. This monitor can measure the beam orbit tilt with a single cavity. We extract the signal of one basic resonance mode from the cavity. This electric field mode is perpendicular to the nominal beam axis, and is excited by beam tilt. The magnitude of extracted signal gives us the beam tilt data. According to our simulation, the expected sensitivity is about 30 nrad.
UCL, London
Royal Holloway, University of London, Surrey
Kyungpook National University, Daegu
KEK, Ibaraki
SLAC, Menlo Park, California
Fermilab, Batavia
University of Cambridge, Cambridge
The ATF2 international collaboration is intending to demonstrate nanometre beam sizes required for the future Linear Colliders. An essential part of the beam diagnostics needed to achieve this goal is the high resolution cavity beam position monitors (BPMs). In this paper we report on the S-band system installed in the final focus region of the new ATF2 extraction beamline. It only includes 4 BPMs, but they are mounted on the most critical final focus magnets squeezing the beam down to 35 nm. We discuss both the design and the first operational experience with the system.
USP/LAL, Sao Paulo
Funding: FAPESP, CNPq
In this work we describe the design of the OTR monitors that will be used to measure beam parameters of the IFUSP Microtron electron beam. The OTR monitor design must allow for efficiency in the entire energy range (from 5 MeV up to 38 MeV in steps of 0.9 MeV), and the devices are planed to monitor charge distribution, beam energy and divergence. An exception is made for the OTR monitor to the 1.7 MeV beam line, which is to be used to monitor only the beam charge distribution at the exit of the linac injector. The image acquisition system is also presented.
TRIUMF, Vancouver
SFU, Burnaby, BC
UBC, Vancouver, B.C.
Funding: TRIUMF receives funding via a contribution agreement through the National Research Council of Canada.
For ISAC at TRIUMF, radioactive isotopes are generated with a 500MeV proton beam. The beam power is up to 40kW and can easily melt the delicate target if too tightly focused. We protect this target by closely monitoring the distribution of the incident proton beam. There is a 3-wire scanner monitor installed near the target; these give the vertical profile and the +45 and -45 degree profiles. Our objective is to use these 3 measured projections to find the 2-D density distribution. By implementing the maximum entropy (MENT) algorithm, we have developed a computer program to realize tomographic reconstruction of the beam density distribution. Of particular concern is to make the calculation sufficiently efficient that an operator can obtain the distribution within a few seconds of the scan. As well, we have developed the technique to perform phase space reconstruction, using many wire scans and the calculated transfer matrices between them. In this paper we present details of the computer code and the techniques used to improve noise tolerance and compute efficiency.
Cosylab, Ljubljana
ORNL RAD, Oak Ridge, Tennessee
ORNL, Oak Ridge, Tennessee
Funding: This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the U.S. Department of Energy.
Implementation of a timing system master device is a complicated task, since a lot of details have to be taken into account even once the architecture decisions have been laid down. At SNS/ORNL timing master controller is being upgraded in collaboration with Cosylab and this paper focuses on some details of its implementation. New timing system master device is based on agile FPGA circuitry and the main focus of this paper is its firmware implementation. Provided are implementation details for event distribution supporting multiple event sources and priorities. Discussed are mechanisms, ensuring deterministic behavior, different methods of encoding that have been employed, and host-independent distribution of time stamp frames. The concept of the super-cycle is explained and its implementation is laid down. Taken into account that implementation for such a complex device involves extensive testing, paper provides insight into verification it was applied. Advantages of the SystemC based test-benches over traditional VHDL-only verification are discussed.
Fermilab, Batavia
Funding: This work was supported by the Fermi National Accelerator Laboratory, which is operated by Universities Research Association, under contract No.DE-AC02-76CH03000 with the U.S. Department of Energy
This talk will present arguments that the Neutrino Factory - an extremely intense source of flavor-tagged neutrinos from muon decays in a storage ring - gives the best physics reach for CP violation, as well as virtually all parameters in the neutrino oscillation parameter space. It will describe the physics capabilities of a baseline Neutrino Factory as compared to other possible future facilities (beta-beam and super-beam facilities), give an overview of the accelerator complex, describe the current international R&D program and present a potential time line for the design and construction of the facility. Although the baseline study focuses on a facility with muon energy of 25 GeV, a concept for a Low-Energy (~ 4 GeV) Neutrino Factory has also been developed and its physics reach will also be discussed. Finally, it will be shown that a facility of this type is unique in that it can present a physics program that can be staged, addressing exciting new physics at each step. Eventually it can lead to an energy-frontier muon collider. A muon accelerator facility is a natural extension that can exploit the high intensity potential at FNAL starting with Project X.
PPPL, Princeton, New Jersey
Funding: Supported by the U.S. Department of Energy.
For applications of high-intensity beams in heavy ion inertial confinement fusion and high energy density physics, solenoidal focusing lattice and transverse wobblers can be used to achieve uniform illumination of the target and for suppressing deleterious instabilities. A generalized self-consistent Kapchinskij-Vladimirskij solution of the nonlinear Vlasov-Maxwell equations is derived for high-intensity beams in a solenoidal focusing lattice with transverse wobblers. The cross-section of the beam is an ellipse with dynamical centroid, titling angle, and transverse dimensions that are determined from 5 envelope-like equations.
LBNL, Berkeley, California
TU Darmstadt, Darmstadt
GSI, Darmstadt
LLNL, Livermore, California
Ion acceleration from high-intensity, short-pulse laser irradiated thin foils has attracted much attention during the past decade. The emitted ion and, in particular, proton pulses contain large particle numbers (exceeding a trillion particles) with energies in the multi-MeV range and are tightly confined in time (< ps) and space (source radius a few micrometers). The generation of these high-current beams is a promising new area of research and has motivated pursuit of applications such as tabletop proton sources or pre-accelerators. Requirements for an injector are controllability, reproducibility and a narrow (quasi-monoenergetic) energy. However, the source provides a divergent beam with an exponential energy spectrum that exhibits a sharp cutoff at its maximum energy. The laser and plasma physics group of the TU Darmstadt, in collaboration with GSI and LBNL, is studying possibilities for transport and RF capture in conventional accelerator structures. First results on controlling laser-accelerated proton beams are presented, supported by WARP simulations.
UCLA, Los Angeles, California
Funding: This work is supported by the DOE Contract No. DE-FG03-92ER40727.
Over the last several years, the Target Normal Sheath Acceleration (TNSA) mechanism in solid density plasmas produced by a laser pulse has achieved proton energies up to 10’s of MeV and quasi-monoenergetic beams at lower energies. Although solid-target experiments have demonstrated high-charge and low-emittance proton beams, little work has been done with gaseous targets which in principle can be operated at a very high repetition frequency. At the Neptune Laboratory, there is an ongoing experiment on CO2 laser driven proton acceleration using a rectangular (0.5x2mm) H2 gas jet as a target. The main goal is to study the coupling of the laser pulse into a plasma with a well defined density in the range of 0.5 to 2 times critical density and characterize the corresponding spectra of accelerated protons. Towards this end, the Neptune TW CO2 laser system is being upgraded to produce shorter 1-3ps pulses. These high-power pulses will allow us to investigate acceleration of protons via the TNSA and Direct Ponderomotive Pressure mechanisms as well as their combination. The current status of the proton source experiment will be presented.
Fermilab, Batavia
Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy
Since the start of Fermilab Collider Run II in 2001, the maximum weekly antiproton accumulation rate has increased from 400·1010 Pbars/week to approximately 3,700·1010 Pbars/week. There are many factors contributing to this increase, one of which involves changes to operational procedures that have streamlined and automated antiproton source production. Automation has been added to our beam line orbit control, stochastic cooling power level management, and RF settings. In addition, daily tuning efforts have been streamlined by implementing sequencer driven aggregates.
GSI, Darmstadt
IPCP, Chernogolovka, Moscow region
TU Darmstadt, Darmstadt
Universidad de Castilla-La Mancha, Ciudad Real
CERN, Geneva
When the LHC will work at full capacity, two counter rotating beams of 7 TeV/c protons will be generated. Each beam will consist of 2808 bunches while each bunch will comprise of 1.15x1011 protons. Bunch length will be 0.5 ns whereas two neighboring bunches will be separated by 25 ns . Intensity in the transverse direction will be Gaussian with σ = 0.2 mm. Each beam will carry 362 MJ energy, sufficient to melt 500 kg of Cu. Safety is an extremely important issue in case of such powerful beams. We report two–dimensional numerical simulations of hydrodynamic and thermodynamic response of a solid copper cylinder that is facially irradiated by one of the LHC beams in axial direction. The energy loss of protons in copper is calculated employing the FLUKA code and this data is used as input to a hydrodynamic code, BIG2. Our simulations show that the beam will penetrate up to 35 m into the solid copper target. Since the target is strongly heated by the beam, a sample of High Energy Density (HED) matter is generated. An additional application of the LHC, therefore will be, to study HED matte. This is an improvement of our previous work [Tahir et al., PRL 94 (2005) 135004].
IUCF, Bloomington, Indiana
LANL, Los Alamos, New Mexico
Funding: LENS is supported by the National Science Foundation grants DMR-0220560 and DMR-0320627, the 21st Century Science and Technology fund of Indiana, Indiana University, and the Department of Defense.
The Indiana University Cyclotron Facility is operating a Low Energy Neutron Source which provides cold neutrons for material research and neutron physics as well as neutrons in the MeV energy range for neutron radiation effects studies. Neutrons are being produced by a 13 MeV proton beam incident on a Beryllium target. The LENS Proton Delivery System (PDS) is routinely operating at 13 MeV and 25 mA at 1.8% duty factor. The RF system, consisting of three Litton 5773 klystron RF tubes at 425 MHz and 1 MW each, power the AccSys Technology PL-13 Linac. The proton beam delivers 6 kilowatts of power to the Beryllium target. Details of the beam spreading system, target cooling system, and accelerator operations will be discussed.
NSCL, East Lansing, Michigan
Funding: This work is supported by the U.S. Department of Energy
The superconducting (SC) driver linac developed for the proposed Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU) will be able to accelerate stable beams of heavy ions to > 200 MeV/u with beam powers up to 400 kW. The driver linac front-end will include ECR ion sources, a bunching system for multi-charge state beams and a radio frequency quadrupole (RFQ). The superconducting linac will have a base frequency of 80.5 MHz primarily using SC cavities and cryomodules developed for the Rare Isotope Accelerator (RIA), the FRIB predecessor. A charge-stripping chicane and multiple-charge state acceleration will be used for the heavier ions in the driver linac. A beam delivery system will transport beam to the in-flight particle fragmentation target station. The paper will discuss recent progress in the accelerator system design for the superconducting driver linac.
SAMEER, Mumbai
The developmental work on linear electron accelerators in SAMEER, India is briefed in this paper. The technology to develop ‘S’ band compact side coupled standing wave electron linear accelerator is very well established at SAMEER, Mumbai center. 6 MV to 15 MV linacs are developed with the desired specifications. Indigenous 6 MV linac machines for radiotherapy applications have been developed successfully and these machines are in use at premier cancer hospitals in the country. SAMEER is presently working on the development of the dual mode-electron and photon and dual photon energy linear accelerator for radiotherapy application. The 6 MeV linac tube development and its test results are discussed.
FZJ, Jülich
University of Erlangen-Nürnberg, Physikalisches Institut II, Erlangen
INFN-Ferrara, Ferrara
The PAX Collaboration is planning experiments using polarized Antiprotons. The only experimentally proven method so far which could lead to the production of polarized antiprotons is the spin-filtering. In particular, spin-filtering has been used to generate polarized protons in an experiment at the Heidelberg TSR*. In order to optimize spin-filtering for the production of polarized antiprotons dedicated experiments are planned at COSY with protons and AD (CERN) with antiprotons. The experimentation at COSY has already started in 2007. A decisive experiment has been performed to settle a long controversy about the role of electrons in the polarization buildup by spin-filtering. Instead of studying the polarization buildup in an initially unpolarized beam, the inverse situation was investigated by observation of depolarization of an initially polarized beam. For the first time the electrons of the electron cooler have been used as a target to study their depolarizing effects on the stored beam. At the same time a series of machine experiments have been performed to study the beam lifetime at different energies.
*F. Rathmann et al., Phys. Rev. Lett. 71, 1993, p.1379
University of Fukui, Faculty of Engineering, Fukui
KURRI, Osaka
FFAG DDS Research Organization, Tokyo
The acceleratorbased neutron source using ERIT (Energy/emittance Recovery Internal Target) scheme has been constructed at KURRI (Kyoto University Research Reactor Institute). And the first beam test was successfully completed in March 2008. In this poster, recent status of beam studies will be presented.
TU Darmstadt, Darmstadt
CERN, Geneva
The REX-ISOLDE radioactive ion beam facility at CERN makes great demands also on the experimentalists due to its specific duty cycle and the time structure with short beam pulses and large intensities. This paper describes the experimentalist's point of view, how to obtain sufficient and correct statistics under the special circumstances arising from the beam time structure. In particular, the case of Coulomb excitation experiments, where a large total cross section is ultimately desired, is studied in greater detail.
ORNL, Oak Ridge, Tennessee
Funding: *Managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
HRIBF produces high-quality beams of short-lived radioactive isotopes for nuclear science research, and is currently unique worldwide in the ability to provide neutron-rich fission fragment beams post-accelerated to energies above the Coulomb barrier. HRIBF is undergoing a multi-phase upgrade. Phase I (completed 2005) was construction of the High Power Target Laboratory to provide the on-going Isotope Separator On-Line development program with a venue for testing new targets, ion sources, and radioactive ion beam (RIB) production techniques with high-power ORIC beams. Presently under way is Phase II, the Injector for Radioactive Ion Species 2, a second RIB production station that will improve facility reliability and accommodate new ion sources, RIB production, and RIB purification techniques, including laser applications. The Phase III goal is to substantially improve facility performance by replacing or supplementing the Oak Ridge Isochronous Cyclotron production accelerator with either a high-power 25-50 MeV electron accelerator or a high-current multi-beam commercial cyclotron. Either upgrade is applicable to R&D on isotope production for medical or other applications.
TRIUMF, Vancouver
The ISAC facility, located at TRIUMF, first began delivering radioactive ion beams (RIBs) in 1998, added post-accelerated beam capability in 2001, and is regarded as one of the premiere RIB facilities in the world. The existing constraints on RIBs of Z<83 and accelerated beams of A/q<30 with energies limited to 5MeV/u are being addressed. A charge-state booster for RIBs has been commissioned to alleviate the A/q<30 restriction and has successfully delivered multi-charge beams through the ISAC accelerators. The 5MeV/u license limit will be removed once an on-line beam monitor is commissioned, allowing beams of up to 11MeV/u to be delivered presently, and increased to over 20MeV/u when the next accelerator phase is installed. In 2008, an actinide target was used to produce RIBs of Z>82; this successful test was performed on a uranium target with yields measured and radiation safety monitored. A new Beam Delivery group has been formed to integrate all aspects of RIB production, which has led to improved efficiency and greater experimental results. These new capabilities will be presented, showing how 2009 promises to be both an exciting and productive year at ISAC.