DESY, Hamburg
International collabollations on high energy physics will be described, referring its long history and with emphasis on the recent activity based on ICFA.
Kyoto University, Photonics and Electronics Science and Engineering Center, Kyoto
In order to establish a shallow implantation of polyatomic carbons, a polyatomic ion source for organic liquids with a high-vapor pressure was developed. Vapor of n-octane was ionized by an electron bombardment, and the ion current of 230 μA was obtained at an extraction voltage of 2 kV. The mass spectra indicated that C3H7 ion was the highest in the ion concentration and some fragmentations of octane molecule took place, which might be caused by the electron bombardment. Depth profile of carbon into single crystalline silicon irradiated with C3H7 or C6H13 at different acceleration voltage was analyzed by X-ray photoelectron spectroscopy. As a result, the implanted depth increased with increase of the acceleration voltage. In addition, the C6H13 was implanted deeper than the C3H7 at the same incident energy per atom even though shallow implantation due to binary collision effect had been expected. The depth profile are also discussed in comparison with computer simulation results.
CERN, Geneva
The role of "Experimental Area Manager" supported by a well organized, charismatic and motivated team is absolutely essential for managing the huge effort needed for a multi-cultural, multi-disciplinary installation of cathedral-size underground caverns housing a billion dollar physics experiment. Between the years 2002 and 2008, we supervised and coordinated the ATLAS work site at LHC, from the end of the civil engineering to the first circulating beams, culminating with 240 workers on the site, 24 hours a day, 7 days a week, with activities taking place simultaneously on the surface, in the 60 m shafts and in the 100 m underground experimental cavern. We depict the activities preparation scheme (including tasks ranging from the installation of 280 ton cranes to super-delicate silicon detectors), the work-site organization method, the safety management that was a top priority throughout the whole project, and the open-communication strategy that required maintaining permanent public visits. The accumulation of experience enables us to summarize the critical success factors for a timely and successful completion of such a vast and complex project.
IFMIF/EVEDA, Rokkasho
CEA, Gif-sur-Yvette
INFN/LNL, Legnaro (PD)
Fusion for Energy, Garching
CIEMAT, Madrid
JAEA, Rokkasho, Kamikita, Aomori
In the frame of the IFMIF/EVEDA project, a high-intensity (125 mA) CW deuteron accelerator will be installed and commissioned at the Rokkasho's Broader Approach (BA) site. The main objective of this 9 MeV prototype is to provide information on the feasibility of the design, the manufacturing and the operation of the two linacs (up to 40 MeV) foreseen for IFMIF*. Based on the requirements for each System (Accelerators, Lithium target and Tests Facility) which are deduced from the IFMIF fusion material irradiation requirements, given by the users, the objectives of this accelerator prototype are defined and presented here. Also, because of the distributed nature of the design work and the procurement of the accelerator, organization of the installation and commissioning phase is essential. The installation and commissioning schemes, the organization proposed and the overall plans are presented.
*IFMIF International Team, IFMIF Comprehensive Design Report (CDR) 2003.
IN2P3-LAPP, Annecy-le-Vieux
INFN/LNF, Frascati (Roma)
Following previous measurements, more detailed preliminary ground motion measurements have been performed at the LNF site for the Super B project site characterization. First, results of vertical ground motion measurements done during 18 hours are shown in order to get an idea of the evolution of the ground motion amplitude with time. Secondly, measurements of ground motion (in the 3 directions of space) were performed at different locations on surface in order to evaluate and to compare the influence of various vibration sources. Then, results of ground motion coherence measured for different distances at two locations close to each other but with soft and rigid floor are compared. These measurements are also compared to the ones done in the ATF2 beam line where a special floor was built for stability. By this way, the results reveal that the LNF is a good site to use ground motion coherence properties for stability like it has been done for ATF2.
INFN/LNF, Frascati (Roma)
U. Sannio, Benevento
The bunch-to-bunch evolution of the electron cloud density can be modeled using a cubic map. The map approach has been proved reliable for RHIC* and LHC**. The coefficients that parameterize the map may be obtained by fitting from time consuming numerical simulations. In this communication we derive a simple approximate formula for the quadratic coefficient, which determines the saturation of the cloud due to space charge, in the electron cloud density map, under the assumptions of round chambers and free-field motion of the elctrons in the cloud. Results are compared with simulations for a wide range of parameters governing the evolution of the elctron cloud.
* U.Iriso, S.Peggs, Phys. Rev.STAB 8, 024403, 2005.
** T.Demma, S.Petracca, G.Rumolo, F.Ruggiero, F.Zimmermann, Phys. Rev.STAB 10, 114401, 2007.
Cosylab, Ljubljana
GSI, Darmstadt
Present GSI control system uses an in-house developed CORBA based middleware called IFC. For FAIR project that will be build on the GSI site, a new control system is foreseen. New devices that are being integrated into the control system preferably will be developed in FESA. In this article, an IFC to FESA gateway will be presented. The gateway provides an intermediate layer that is able to talk to FESA device servers on one side and provide their functionality to existing IFC clients. The gateway will allow coexistence of FESA front-end implementations and existing GSI device servers, providing a smooth transition path to the future FAIR front-end environment. New GSI and FAIR devices that will be implemented in FESA will have to match GSI standards for nomenclature and device modeling. Exact match of new devices is not possible due to different hardware and software architecture of the new system, therefore a gateway solution is required. The gateway can translate the complete device model, including conversion from FESA to GSI data types. In the process of gateway design and implementation, valuable input was collected for the design of the future FAIR control system.
LAL, Orsay
Within the XFEL project Laboratoire d'Accélérateur Linéaire (LAL) is engaged to deliver 800 fundamental power couplers operating at 1.3 GHz at nominal power of 120 kW for the superconducting linac. This paper presents the strategies chosen for industrial production along with that of conditioning so as to deliver couplers at the rate of 8 per week.
BARC, Mumbai
BARC is involved in the development of superconducting cavities for Accelerator Driven Sub-critical System (ADSS). The performance of superconducting RF structure can be greatly affected due to multipacting. Hence 2D and 3D multipaction simulation studies have been carried out for a medium velocity (β=0.49) elliptical Niobium cavity operating at 1050 MHz. An in-house code has been developed which uses finite element method based software to calculate electromagnetic field of the structure. Leap frog method algorithm has been used to solve Lorenz force equation for trajectory tracking of electrons which are launched inside from different initial positions. Electron trajectories are tracked until they hit the surface. An interpolation function is used to calculate SEY at different impact energies. By repeating the process at different field level for different primary electrons multipacting field levels are identified. The study revealed that the cavity structure is not multipacting prone up to 17 MV/m average accelerating field. Two point first order multipacting is observed at the equatorial region of the cavity when the accelerating field is between 18 MV/m and 28 MV/m.
Imperial College of Science and Technology, London
Imperial College of Science and Technology, Department of Physics, London
Cockcroft Institute, Lancaster University, Lancaster
The ever-growing demand for higher beam energies has dramatically increased the risk of RF breakdown, limiting the maximum achievable accelerating gradient. Field emission is the most frequently encountered RF breakdown where it occurs at regions of locally enhanced electric field. Electrons accelerated across the cavity as they tunnel through the surface in the presence of microscopic defects. Upon Impact, most of the kinetic energy is converted into heat and stress. This can inflict irreversible damage to the surface, creating additional field emission sites. This work aims to investigate, through simulation, the physics involved during both emission and impact of electrons. A newly developed 3D field model of an 805 MHz cavity is generated by COMSOL Multiphysics. Electron tracking is performed using a Matlab based code, calculating the relevant parameters needed by employing fourth Order Runge Kutta integration. By studying such behaviours in 3D, it is possible to identify how the cavity surface can alter the local RF field and lead to breakdown and subsequent damages. The ultimate aim is to introduce new surface standards to ensure better cavity performance.
JINR, Dubna, Moscow Region
The investigations on ILC siting in the Dubna region and ILC technical activity at JINR are presented. International intergovernmental status of JINR, stable geological and plain relief conditions, comfortable location and well developed infrastructure create a set of advantages of the JINR site in the neighborhood of Dubna. The shallow layout of accelerator tunnel makes it possible to use a communication gallery at the surface instead of second one. This is an effective way of significant cost reduction of all conventional facilities and explicit labor of the project. The results of the preliminary geological engineering surveys along the supposed route of the ILC in Dubna area of Moscow region are presented.
CERN, Geneva
GSI, Darmstadt
The Chair and Deputy will receive the award of the IPAC'10 Organizing Committee on behalf of the JACoW Collaboration.
DAE/VECC, Calcutta
K500 Superconducting Cyclotron (SCC) is already commissioned successfully at VECC, Kolkata by accelerating Ne3+ internal beam with 70 nA beam current at 670 mm extraction radius. The Radio Frequency cavity of SCC is successfully operational since last two years. All these years were very challenging and worthy period from the point of view of gaining experience and knowledge by solving fabrication and assembly problems faced during construction of 10 m tall copper made coaxial RF cavities and tackling RF related commissioning problems. RF system operates within the frequency range of 9 to 27 MHz for generating maximum 100 kV DEE voltage. The construction of the RF system demands making of numerous critical soldering and brazing joints including joints between ceramic and copper along with maintaining close dimensional accuracies, assembly tolerances, mirror symmetricity, surface finish and utmost cleanliness. This paper presents the details of fabrication and installation procedures and their effects on the final performance of the cavities. It also highlights the problems faced during the commissioning process of the RF cavities.
DESY, Hamburg
Building an accelerator facility brings together civil construction and mechanical engineering, two trades with very different working cultures, practices and tool sets: While construction sites are traditionally paper-based and 2D oriented, the accelerator and its infrastructure are completely modeled in 3D. At the European XFEL, methods and tools known from plant construction were introduced to civil construction to enable efficient collaboration of all trades. Integrated 3D models encompass design models of all technical subsystems. An electronic "XFEL room book" captures requirements and manages assignments of space, infrastructure and equipments in the buildings. The DESY Engineering Data Management System (EDMS) manages and links the information with additional documentation. Electronic workflows coordinate e.g. reviews and change management. 3D models, room book and documentation databases together constitute the so-called "Building Information Model" (BIM). The BIM addresses the entire building lifecycle and is a basis for later facility operation. The poster describes information management procedures, tools and experience in the civil construction of the European XFEL.
NSRRC, Hsinchu
The electric power system of Taiwan Photon Source (TPS) will be installed during the construction of TPS. Many power electronic devices which produce large nonlinear loads will be used in the new power system and the accelerator facility. The capacitor banks will also be used for the power factor correction. Thus, the excessive harmonic waveform distortion level on the normal waveform will be presented continuously. These excessive harmonic current flows will result in transformer and cable over-heating and many types of circuit faults, and also wasting energy. A project is initiated to study these harmonic effects which will appear in the electric power system of TPS. A computer simulation approach is used to study the harmonic waveform distortion phenomena, and also to investigate an effective approach to reduce it. The harmonic effects of selected section of TLS (Taiwan Light Source) electric power system, and those appear at the mock segment of 1/24 accelerator of TPS system are measured and compared with the simulated results.
Sheffield University, Sheffield
University of Warwick, Coventry
STFC/RAL/ISIS, Chilton, Didcot, Oxon
STFC/RAL, Chilton, Didcot, Oxon
Recently reported results on the tungsten lifetime/fatigue tests under conditions expected in the Neutrino Factory target have strengthened the case of solid target option for a Neutrino Factory. This paper gives description of the detailed measurements of the tungsten properties at high temperature and high stress. We have performed extensive set of measurements of the surface displacement and velocity of the tungsten wires that were stressed by passing a fast, high current pulse through a thin sample. Radial and longitudinal oscillations of the wire were measured by a Laser Doppler Vibrometer. The wire was operated at temperatures of 300-2500 K by adjusting the pulse repetition rate. In doing so we have tried to simulate the conditions (high stress and temperature) expected at the Neutrino Factory. Most important result of this study is an experimental confirmation that strength of tungsten remains high at high temperature and high stress. The experimental results have been found to agree very well with LS-DYNA modelling results.
KIT, Karlsruhe
KCETA, Eggenstein-Leopoldshafen
Cosmic ray particles can produce extended air showers that have a total energy of more than 100 EeV, which is a hundred million times more than the TeV particles that we produce in accelerators. How do the cosmic accelerators work? Where are they and what are they accelerating? How do the supposedly extragalactic particles propagate to Earth? Do they offer a new kind of astronomy? The Pierre Auger Observatory is an international project dedicated to find answers to these - and many more - questions. The presentation reviews the goals, achievements and plans for a better understanding of ultra-high energy cosmic rays.