ODU, Norfolk, Virginia
Using high-pressure RF cavities for muon colliders would provide higher accelerating gradients, that is crucial for fast acceleration of short-living muons .This approach requires a good evaluation for mechanisms of muon - low-Z gas interaction, including such effects as multiple scattering and space charge effects. Most present simulation tools (GEANT4, G4MICE) for muon beams are based on single particle tracking, where collective effects are not taken into account. We use a modified molecular dynamic simulation technique to study effects of both multiple scattering and space charge screening by the gas on scattering, energy loss, and propagation of muons during both ionization cooling and acceleration.
Imperial College of Science and Technology, Department of Physics, London
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. In May 2010 it is expected that the beam and most detectors will be commissioned and the time of the first measurement of input beam emittance closely approaching. The plan of steps of measurements of emittance and cooling, that will follow in the rest of 2010 and later, will be reported.
This abstract is submitted by the chear of the MICE speaker bureau. A member of the collaboration will be soon identified to present the poster and added a co-author.
Osaka University, Osaka
FFAG lattices with racetrack-shape has been studied to cool muon beams. The ring has straight sections with FFAG magnets, which makes enough space to install kicker magnets to inject and extract the muon beam. Wedge absorbers using superfluid helium and RF cavities are installed to the ring. This paper reports progress of the study.
Osaka University, Osaka
The COMET is an experiment to search for the process of muon to electron conversion in a muonic atom, and is in its design phase to be carried out at J-PARC in near future. The experiment uses a long superconducting solenoid channels from a pion production target to a detector system. In order, to study the solenoid channel the g4beamline is used for the magnetic field calculation and beam tracking. This paper reports the status of the simulation studies.
IHEP Beijing, Beijing
MPI-P, München
MPI für Physics, Muenchen
Low energy muon beams are useful for a wide range of physics experiments. High quality muon beams are also required for muon colliders and neutrino factories. The frictional cooling method holds promise for delivering slow muon beams with narrow energy spreads. With this technology, we consider the production of a cold muon beam from a surface muon source, such as that at the Paul Scherrer Institute. A cooling scheme based on frictional cooling is outlined. Simulation results show that the efficiency of slow muon production can be raised to 1%, which is significantly higher than current schemes.
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
Imperial College of Science and Technology, Department of Physics, London
CERN, Geneva
Fermilab, Batavia
BNL, Upton, Long Island, New York
Muons, Inc, Batavia
LBNL, Berkeley, California
We discuss alternative designs of the muon capture front end of the Neutrino Factory International Design Study (IDS). In the front end, a proton bunch on a target creates secondary pions that drift into a capture channel, decaying into muons. 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. This design is affected by limitations on accelerating gradients within magnetic fields. The effects of gradient limitations are explored, and mitigation strategies are presented.
Imperial College of Science and Technology, Department of Physics, London
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
The Neutrino Factory is a planned particle accelerator complex that will produce an intense, focused neutrino beam, using neutrinos from muon decay. Such high neutrino intensities can only be achieved by reducing the muon beam emittance using an ionization cooling system. The G4MICE software is used to study the performance of various cooling cell configurations. A comparison is drawn between the cooling in the FS2 cells, the baseline Neutrino Factory and doublet cells. The beam dynamics in each of cooling channels are presented. The lattices are compared with respect to the equilibrium emittance, muon transmission, acceptance and evolution of emittance along the channel. Conclusions for a possible optimisation of the future muon cooling channel of the Neutrino Factory are presented.
Imperial College of Science and Technology, Department of Physics, London
OXFORDphysics, Oxford, Oxon
In the Muon Ionization Cooling Experiment (MICE) at RAL muons are produced and transported in a dedicated beamline connecting the production point (target) to the diffuser, a mechanism inside the first spectrometer solenoid designed to inflate the initial normalized emittance up to 10 mm rad in a controlled fashion. In order to match the incoming muons to the downstream experiment, covering all the possible values of the emittance-momentum matrix, an optimisation procedure has been devised which is based upon a genetic algorithm coupled to the tracking code G4Beamline. Details of beamline tuning and initial measurements are discussed.
Imperial College of Science and Technology, Department of Physics, London
DPNC, Genève
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
Monitoring the muon beam properties in the final stage of the Neutrino Factory (the Decay Ring) is important for the understanding of the beam itself and a crucial piece of information for the downstream physics detectors. The main topics to be assessed are: knowledge of the muon beam energy, divergence of the muon beam and muon beam current. In the framework of the International Design Study for the Neutrino Factory (IDS-NF) a Race Track model Decay Ring based on G4beamline has been produced to understand how electrons from muon decays can be used to infer the energy properties of the beam via the spin depolarisation technique. The use of other codes, like Zgoubi, to generate a realistic beam including effects like spin polarisation, are considered. A general discussion on the remaining topics is presented.
Imperial College of Science and Technology, Department of Physics, London
STFC/RAL/ISIS, Chilton, Didcot, Oxon
The international Muon Ionisation Cooling Experiment (MICE) is designed to provide a proof of principal of the ionisation cooling technique proposed to reduce the muon beam phase space at a future Neutrino Factory or Muon Collider. The pion production target is a titanium cylinder that is dipped into the proton beam of the Rutherford Appleton Laboratory's ISIS 800 MeV synchrotron. Studies of the particle rate in the MICE muon beam are presented as a function of the beam loss induced in ISIS by the MICE target. The implications of the observed beam loss and particle rate on ISIS operation and MICE data taking is discussed.
Imperial College of Science and Technology, Department of Physics, London
Fermilab, Batavia
The COherent Muon to Electron Transition (COMET) experiment aims to measure muon to electron conversion with an unprecedented sensitivity of less than 1 in 10 million billion. The COMET experiment was given stage 1 approval by the J-PARC Program Advisory Committee in July 2009 and work is currently underway towards preparing a technical design report for the whole experiment. The need for this sensitivity places several stringent requirements on the beamline, such as, a pulsed proton beam with an extinction level between pulses of 9 orders of magnitude; a 5T superconducting solenoid operating near a high radiation environment; precise momentum selection of a large emittance muon beam and momentum selection and collimation of a large emittance electron beam. This paper will present the current status of the various components of the COMET beamline.
Imperial College of Science and Technology, Department of Physics, London
UMAN, Manchester
Cockcroft Institute, Warrington, Cheshire
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
Osaka University, Osaka
Fermilab, Batavia
KURRI, Osaka
UCL, London
FZJ, Jülich
KEK/JAEA, Ibaraki-Ken
STFC/RAL, Chilton, Didcot, Oxon
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
JAI, Oxford
The next generation of lepton flavour violation experiments will use high intensity and high quality muon beams. Such beams can be produced by sending a short proton pulse to the pion production target, capturing pions and performing RF phase rotation on the resulting muon beam in an FFAG ring, which was proposed for the PRISM project. A PRISM task force was created to address the accelerator and detector issues that need to be solved in order to realise the PRISM experiment. The parameters of the initial proton beam required and the PRISM experiment are reviewed. Alternative designs of the PRISM FFAG ring are presented and compared with the reference design. The ring injection/extraction system, matching with the solenoid channel and progress on the ring's main hardware systems like RF and kicker magnet are discussed. The activity on the simulation of a high sensitivity experiment and the impact on physics reach is described. The progress and future directions of the study are presented in this paper.
Imperial College of Science and Technology, Department of Physics, London
BNL, Upton, Long Island, New York
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
JAI, Oxford
Nonscaling FFAG is required for the muon acceleration in the Neutrino Factory, which baseline design is under investigation in the International Design Study (IDS-NF). In order to inject/extract the muon beam with a very large emittance, several strong kickers with a very large aperture are required distributed in many lattice cells. Once the sufficient orbit separation is obtained by the kickers, the final degree of separation from the lattice is made by the septum, which needs to be superconducting. The geometry of the symmetric solutions allowing to inject/extract both signs of muons is presented. The preliminary design of the kicker and septum magnets is given.
Imperial College of Science and Technology, Department of Physics, London
BNL, Upton, Long Island, New York
JLAB, Newport News, Virginia
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
The IDS study showed that a Neutrino Factory seems to be the most promising candidate for the next phase of high precision neutrino oscillation experiments. A part of the increased precision is due to the fact that in a Neutrino Factory the decay of muons produces a neutrino beam with narrow energy distribution and divergence. The effect of beam loading on the energy distribution of the muon beam in the Neutrino Factory has been investigated numerically. The simulations have been performed using the baseline accelerator design including cavities for different number of bunch trains and bunch train timing. A detailed analysis of the beam energy distribution expected is given together with a discussion of the energy spread produced by the gutter acceleration in the FFAG and the implications for the neutrino oscillation experiments will be presented.
OXFORDphysics, Oxford, Oxon
The Muon Ionization Cooling Experiment is one lattice section of a cooling channel suitable for conditioning the muon beam at the front end of a Neutrino Factory or Muon Collider. Scintillating fibre spectrometers and 50 ps resolution timing detectors provide the unprecedented opportunity to measure the initial and final six-dimensional phase space vectors of individual muons. The capability of MICE to study the evolution of muon beams through a solenoidal lattice will be described.
Sheffield University, Sheffield
The MICE experiment requires a beam of low energy muons to demonstrate muon cooling. A target mechanism has been developed that inserts a small titanium target into the circulating ISIS beam during the last 2ms before extraction. The target mechanism has been in operation in the ISIS beam during 2009 and a large set of useful data has been obtained describing the target's operational parameters. This has allowed the commissioning of the initial section of the MICE beam line and instrumentation, and the close monitoring of target performance. This work describes these target parameters and presents some of the results from operational shifts.
Sheffield University, Sheffield
STFC/RAL, Chilton, Didcot, Oxon
The MICE experiment uses a beam of low energy muons to test the feasibility of ionisation cooling. This beam is derived parasitically from the ISIS accelerator at the Rutherford Appleton Laboratory. A target mechanism has been developed and deployed that rapidly inserts a small titanium target into the circulating proton beam immediately prior to extraction without undue disturbance of the primary ISIS beam. The first target drive was installed in ISIS during 2008 and operated successfully for over 100,000 pulses. A second upgraded design was installed in 2009 and is currently in operation. The technical specification for this upgraded design is given and the motivation for many of the improvements is discussed. In addition possible future improvements to the current design are discussed.
Fermilab, Batavia
BNL, Upton, Long Island, New York
IIT, Chicago, Illinois
LBNL, Berkeley, California
An accelerator complex that can produce ultra-intense beams of muons presents many opportunities to explore new physics. A facility of this type is unique in that, in a relatively straightforward way, it can present a physics program that can be staged and thus move forward incrementally, addressing exciting new physics at each step. At the request of the US Department of Energy's Office of High Energy Physics, the Neutrino Factory and Muon Collider Collaboration and the Fermilab Muon Collider Task Force have recently submitted a proposal to create a Muon Accelerator Program that will have, as a primary goal, to deliver a Design Feasibility Study for an energy-frontier Muon Collider after a 7 year R&D program. This paper presents a description of a Muon Collider facility with a brief physics motivation, gives an overview of the proposal with respect to its organization and timeline and then discusses in some detail its major technical components.
Fermilab, Batavia
Imperial College of Science and Technology, Department of Physics, London
To demonstrate the feasibility of a high pressure RF cavity for use in the cooling channel of a muon collider, an experimental setup that utilizes 400-MeV Fermilab linac proton beam has been developed. In this paper, we describe the beam diagnostics and the collimator system for the experiment, and report the initial results of the beam commissioning. The transient response of the cavity to the beam is measured by the electric and magnetic pickup probes, and the beam-gas interaction is monitored by the optical diagnostic system composed of a spectrometer and two PMTs.
Fermilab, Batavia
ANL, Argonne
Ionization cooling is a critical building block for the realization of a muon collider. To suppress breakdown in the presence of the external magnetic field, an idea of using an RF cavity filled with high pressure hydrogen gas is being considered for the cooling channel design. In the high pressure RF cavity, ionization energy loss and longitudinal momentum recovery can be achieved simultaneously. One possible problem expected in the high pressure RF cavity is, however, the dissipation of significant RF power through the electrons accumulated inside the cavity. The electrons are generated from the beam-induced ionization of the high pressure gas. To characterize this detrimental loading effect, we develop a simplified model that relates the electron density evolution and the observed pickup voltage signal in the cavity, with consideration of several key molecular processes such as the formation of the polyatomic molecules and ions, excitation, recombination and electron attachment. This model is expected to be compared with the actual beam test of the cavity in the MuCool Test Area (MTA) of Fermilab.
Fermilab, Batavia
CERN, Geneva
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
Muons, Inc, Batavia
We discuss the design of the muon capture front end of a neutrino factory and present studies of variations of its components. In the front end, a proton bunch on a target creates secondary pions that drift into a capture transport channel, decaying into muons. 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. The cooling section uses absorber material (reducing the 3-D muon momenta) alternating with rf cavities (restoring longitudinal momentum) within strong focusing magnetic fields. The design is affected by limitations on accelerating gradients within magnetic fields. The effects of gradient limitations are explored, and mitigation strategies are presented. Variations of the ionization cooling and acceleration scenarios and extensions toward use in a muon collider are discussed.
Fermilab, Batavia
Muons, Inc, Batavia
IIT, Chicago, Illinois
ANL, Argonne
University of Chicago, Chicago, Illinois
Voss Scientific, Albuquerque, New Mexico
A high pressurizing hydrogen gas filled RF cavity has a great potential to apply for muon colliders. It generates high electric field gradients in strong magnetic fields with various conditions. As the remaining demonstration, it must work under high radiation conditions. A high intensity muon beam will generate a beam-induced electron swarm via the ionization process in the cavity. A large amount of RF power will be consumed into the swarm. We show the recent non-beam test and discuss the electron swarm dynamics which plays a key role to develop a high pressure RF cavity.
Muons, Inc, Batavia
Northern Illinois University, DeKalb, Illinois
Muon Colliders produce high rates of unwanted particles near the beams in the detector regions. Previous designs have used massive shielding to reduce these backgrounds, at a cost of creating dead regions in the detectors. To optimize the physics from the experiments, new ways to instrument these regions are needed. Since the last study of a muon collider detector in the 1990s, new types of detectors, such as solid state photon sensors that are fine-grained, insensitive to magnetic fields, radiation-resistant, fast, and inexpensive have become available. These can be highly segmented to operate in the regions near the beams. We re-evaluate the detector design, based on new sensor technologies. Simulations that incorporate conditions in recent muon collider interaction region designs are used to revise muon collider detector parameters based on particle type and occupancy. Shielding schemes are studied for optimization. Novel schemes for the overall muon collider design, including "split-detectors", are considered.
Muons, Inc, Batavia
Fermilab, Batavia
A helical cooling channel (HCC) consisting of a pressurized gas absorber imbedded in a magnetic channel that provides solenoidal, helical dipole and helical quadrupole fields has shown considerable promise in providing six-dimensional cooling for muon beams. The energy lost by muons traversing the gas absorber needs to be replaced by inserting RF cavities into the HCC lattice. Replacing the substantial muon energy losses using RF cavities with reasonable gradients will require a significant fraction of the channel length be devoted to RF. However to provide the maximum phase space cooling and minimum muon losses, the HCC should have a short period and length. In this paper we examine an approach where each HCC cell has an RF cavity imbedded in the aperture with the magnetic coils are split allowing for half of the cell length to be available for the RF coupler and other services.
Muons, Inc, Batavia
Fermilab, Batavia
Intense muon beams have many potential applications, including neutrino factories and muon colliders. However, muons are produced as tertiary beams, resulting in diffuse phase space distributions. To make useful beams, the muons must be rapidly cooled before they decay. An idea conceived recently for the collection and cooling of muon beams, namely, the use of a Quasi-Isochronous Helical Channel (QIHC) to facilitate capture of muons into RF buckets, has been developed further. The resulting distribution could be cooled quickly and coalesced into a single bunch to optimize the luminosity of a muon collider. After a brief elaboration of the QIHC concept, some recent developments are described.
LBNL, Berkeley, California
BNL, Upton, Long Island, New York
A Neutrino Factory requires an intense and highly cooled (in transverse phase space) muon beam. We discuss a hybrid approach for a linear 4D cooling channel consisting of high-pressure gas-filled RF cavities –potentially allowing high gradients without breakdowns– and discrete LiH absorbers to provide the necessary energy loss that results in the needed muon beam cooling. We report simulations of the channel performance and its comparison with the vacuum case; we also discuss the various technical and safety issues associated with cavities filled with high-pressure hydrogen gas. Even with additional windows that might be needed for safety reasons, the channel performance is comparable to that of the original, all-vacuum Feasibility Study 2a channel on which our design is based. If tests demonstrate that the gas-filled RF cavities can operate properly with an intense beam of ionizing particles passing through them, our approach would be an attractive way of avoiding possible breakdown problems with a vacuum RF channel.
LANL, Los Alamos, New Mexico
We propose a high-gradient linear accelerator for accelerating low-energy muons and pions in a strong solenoidal magnetic field. The acceleration starts immediately after collection of pions from a target by solenoidal magnets and brings muons to a kinetic energy of about 200 MeV over a distance of the order of 10 m. At this energy, both an ionization cooling of the muon beam and its further acceleration in a superconducting linac become feasible. The project presents unique challenges ' a very large energy spread in a highly divergent beam, as well as pion and muon decays ' requiring large longitudinal and transverse acceptances. One potential solution incorporates a normal-conducting linac consisting of independently fed 0-mode RF cavities with wide apertures closed by thin metal windows or grids. The guiding magnetic field is provided by external superconducting solenoids. The cavity choice, overall linac design considerations, and simulation results of muon acceleration are presented. While the primary applications of such a linac are for homeland defense and industry, it can provide muon fluxes high enough to be of interest for physics experiments.
LANL, Los Alamos, New Mexico
Many groups are working on muon accelerators for future neutrino factory and muon colliders. One of the applications of muon accelerator is muon radiography which is a promising method to investigate large objects taking advantage of the long penetration lengths of muons. We propose a compact muon accelerator that has a large energy and a phase acceptance to capture relatively low energy pion/muon of 10 - 100 MeV and accelerates them to 200 MeV without any beam cooling. Like an RFQ, mixed buncher/acceleration mode provides phase bunching during the acceleration. Our current design uses 805 MHz zero-mode normal-conducting cavities with 35 MV/m peak field*. The normal conducting cavities are surrounded by superconducting coils that produce 5 T focusing field. We ran Monte Carlo simulations to optimize linac parameters such as frequency and acceleration gradient. Muon energy loss and scattering effects at the cavity windows are studied, too. The simulation showed that about 10 % of the pion/muon injected into the linac can be accelerated to 200 MeV. Further acceleration is possible with superconducting linac.
* S. Kurennoy et al., IPAC 2010.
UCLA, Los Angeles, California
RadiaBeam, Marina del Rey
One of the challenges of the proposed muon collider is the beam size at the interaction region. The current target for the beta function (beta-star) is 10mm for the 1.5TeV scenario with a beam emittance of 25mm-mrad. In this paper, we describe the design and development of a final focusing scheme that attempts to reach these parameters. The final focus scheme is based on the use of permanent magnet quadrupoles (PMQ) in a triplet configuration. Initial simulations show that the PMQs reach gradients as high as ~990T/m using Praseodymium based magnets in a Halbach style arrangement. Possible methods for tuning the PMQs at the interaction region, via temperature control and high-resolution movers, are also described.
PU, Princeton, New Jersey
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
ORNL, Oak Ridge, Tennessee
CERN, Geneva
EBG MedAustron, Wr. Neustadt
BNL, Upton, Long Island, New York
Fermilab, Batavia
PPPL, Princeton, New Jersey
We report on the analysis of data collected in the MERIT experiment at CERN during the Fall of 2007. These results validate the concept of a free mercury jet inside a high-field solenoid magnet as a target for a pulsed proton beam of 4-MW power, as needed for a future Muon Collider and/or Neutrino Factory.
UCR, Riverside, California
Imperial College of Science and Technology, Department of Physics, London
Sofia University St. Kliment Ohridski, Faculty of Physics, Sofia
The Muon Ionization Cooling Experiment (MICE) is being built at the Rutherford Appleton Laboratory (RAL) to test ionization cooling of a muon beam. Successful demonstration of cooling is a necessary step along the path toward creating future high intensity muon beams in either a Neutrino Factory or Muon Collider. Production of particles in the MICE beamline begins with a titanium target dipping into the ISIS proton beam. The resulting pions are captured, momentum-selected, and fed into a 5T superconducting decay solenoid which contains the pions and their decay muons. Another dipole then selects the final particles for propagation through the rest of the MICE beamline. Within the last year, the MICE target has been redesigned, rebuilt, and has begun operating in ISIS. The decay solenoid has also become operational, dramatically increasing the number of particles in the MICE beamline. In parallel, particle identification detectors have also been installed and commissioned. In this paper, the commissioning of the improved MICE beamline and target will be discussed, including the use of Time-of-Flight detectors to understand the content of the MICE beam between 200 and 444 MeV/c.
UCR, Riverside, California
A significant reduction in the six-dimensional emittance of the initial beam is required in any proposed Muon Collider scheme. Two lattices based on the original RFOFO ring design representing different stages of cooling are considered. One is the so-called open cavity lattice addressing the problem of the 201.25 MHz RF cavities running in a magnetic field, the other one is the 805 MHz RF lattice that is used for smaller emittances. The details of the acceptance analysis and tracking studies of both channels are presented and compared to the independent ICOOL implementation.
UCR, Riverside, California
Fermilab, Batavia
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
In the Muon Ionization Cooling Experiment (MICE), muons are cooled by ionization cooling. Muons are passed through material, reducing the total momentum of the beam. This results in a decrease in transverse emittance and a slight increase in longitudinal emittance, but overall reduction of 6D beam emittance. In emittance exchange, a dispersive beam is passed through wedge-shaped absorbers. Muons with higher energy pass through more material, resulting in a reduction in longitudinal and transverse emittance. Emittance exchange is a vital technology for a Muon Collider and may be of use for a Neutrino Factory. Two ways to demonstrate emittance exchange in the straight solenoidal lattice of MICE are discussed. One is to let a muon beam pass through a wedge shaped absorber; the input beam distribution must be carefully selected to accommodate chromatic aberrations in the solenoid lattice. Another approach is to use the input beam for MICE without beam selection. In this case no polynomial weighting is involved; however, a more sophisticated shape of the absorber is required to reduce longitudinal emittance.
ODU, Norfolk, Virginia
JLAB, Newport News, Virginia
BNL, Upton, Long Island, New York
Recirculating linear accelerators (RLA) are the most likely means to achieve the rapid acceleration of short-lived muons to multi-GeV energies required for Neutrino Factories and TeV energies required for Muon Colliders. In the work described here, a novel arc optics based on a Non Scaling Fixed Field Alternating Gradient (NS-FFAG) lattice is developed, which would provide sufficient momentum acceptance to allow multiple passes (two or more consecutive energies) to be transported in one string of magnets. We present a combination of the non-scaling NS-FFAG RLA placed in a straight section. Orbit offsets of different energy muons are kept small in the NS-FFAG arcs during multiple passes. The NS-FFAG, made of densely packed FODO cells, allows momentum acceptance of dp/p=±60%. This solution would reduce overall cost and simplify the operation. Difference in a muon path length for corresponding energies is corrected with a chicane. We will also discuss technical requirements to allow the maximum number of passes by using an adjustable path length to accurately control the returned beam phase to synchronize with the RF.
BNL, Upton, Long Island, New York
By providing an extremely intense source of neutrinos from the decays of muons in a storage ring, a Neutrino Factory will provide the opportunity for precision measurements and searches for new physics amongst neutrino interactions. An active international collaboration is addressing the many technical challenges that must be met before the design for a Neutrino Factory can be finalized. An overview of the accelerator complex and the current international R&D program will be presented, and the key technical issues will be discussed.
JLAB, Newport News, Virginia
Muons, Inc, Batavia
Neutrino Factories and Muon Colliders require rapid acceleration of short-lived muons to multi-GeV and TeV energies. A Recirculating Linear Accelerator (RLA) that uses superconducting RF structures can provide exceptionally fast and economical acceleration to the extent that the focusing range of the RLA quadrupoles allows each muon to pass several times through each high-gradient cavity. A new concept of rapidly changing the strength of the RLA focusing quadrupoles as the muons gain energy is being developed to increase the number of passes that each muon will make in the RF cavities, leading to greater cost effectiveness. We discuss the optics and technical requirements for RLA designs, using RF cavities capable of simultaneous acceleration of both μ+ and μ- species, with pulsed Linac quadrupoles and arc magnets to allow the maximum number of passes. The design will include the optics for the multi-pass linac and droplet-shaped return arcs.