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cryogenics

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MOXAGM01 Status of the Large Hadron Collider (LHC) quadrupole, controls, collider, dipole 1
 
  • F. Bordry
    CERN, Geneva
  The status of the LHC commissioning is presented. Preparation for smooth beam commissioning is going on since several years:
  1. very thorough commissioning of the highly complex hardware systems started already in 2005
  2. preparation of the LHC beam commissioning, resulting in detailed procedures for various commissioning phases with increasing beam intensity and performance
  3. preparation of the injector complex, with beam up to the end of the transfer lines between SPS and LHC.
 
slides icon Slides  
 
MOYBGM01 Global R&D Effort for the ILC Linac Technology linac, linear-collider, acceleration, collider 12
 
  • A. Yamamoto
    KEK, Ibaraki
  The presentation will cover the ongoing ILC R&D program in the field of superconducting accelerating structures, accelerator modules and rf systems. In addition to technical/scientific aspects, a view of the organisational challenges of this global R&D programme and how they are addressed will be described.  
slides icon Slides  
 
MOZDM01 LHC Hardware Commissioning Summary dipole, extraction, controls, instrumentation 56
 
  • R. I. Saban
    CERN, Geneva
  The presentation summarizes the main phases of the LHC hardware commissioning and discusses especially the powering of one completer sector to the nominal current.  
slides icon Slides  
 
MOPC101 Design Considerations of Fast-cycling Synchrotrons Based on Superconducting Transmission Line Magnets proton, power-supply, synchrotron, target 301
 
  • H. Piekarz, S. Hays, Y. Huang, V. D. Shiltsev
    Fermilab, Batavia, Illinois
  Fast cycling synchrotrons have become necessary components of contemporary accelerator systems for advanced nuclear and high-energy physics programs. We explore a possibility of using super-ferric dipole magnets of up to 2 Tesla B-field powered by a superconducting transmission line conductor. We present both the LTS and the HTS conductor design options for these magnets and their impact on both static and dynamic power losses with operation cycles from o.5 Hz to 5 Hz, depending on the beam energy and the size of the accelerator ring. We also discuss expected B-field quality and the corrector magnets options. We outline magnet string inter-connections and creation of space for the corrector magnets and discuss option for a superconducting dump switch of the quench protection system.  
 
MOPC110 Commissioning of the Heidelberg Cryogenic Trap for Fast Ion Beams (CTF) vacuum, ion, radiation, target 319
 
  • M. Lange, K. Blaum, M. Froese, M. Grieser, D. Kaiser, S. Menk, D. Orlov, A. Shornikov, T. Sieber, J. Varju, A. Wolf, R. von Hahn
    MPI-K, Heidelberg
  • O. Heber, M. Rappaport, J. Toker, D. Zajfman
    Weizmann Institute of Science, Physics, Rehovot
  At the MPI für Kernphysik, a cryogenic electrostatic heavy-ion storage ring (CSR) is being developed. As a cryogenic test facility (CTF), an electrostatic ion beam trap is nearing completion. It will store ions between two electrostatic mirrors, confining them radially by two einzel lenses set apart by 30 cm. This linear, open design leaves room for testing beam diagnostic devices developed for the CSR, e.g. split ring electrodes and a residual gas monitor. As for the CSR, parts of the vacuum system will be brought in direct contact with superfluid helium, to achieve an operating temperature of 2-10 K. Under these conditions, we expect residual gas pressures in the 10-15 mbar range, and storage times on the order of minutes for light molecular ions. We will present first results from the commissioning of the CTF, especially the temperatures and residual gas pressures reached in the trap, as well as experiences with the position stability of the mechanical suspension of the trap electrodes in cryogenic operation.  
 
MOPC118 Coordination of the Commissioning of the LHC Technical Systems controls, dipole, collider, quadrupole 340
 
  • R. I. Saban, B. Bellesia, M. P. Casas Lino, C. Fernandez-Robles, M. Pojer, R. Schmidt, M. Solfaroli Camillocci, A. Vergara-Fernández
    CERN, Geneva
  The Large Hadron Collider operation relies on 1232 superconducting dipoles with a field of 8.33T and 400 superconducting quadrupoles with a strength of 220 T/m powered at 12kA, operating in superfluid He at 1.9K. For dipoles and quadrupoles as well as for many other magnets more than 1700 power converters are necessary to feed the superconducting circuits. A sophisticated magnet protection system is crucial to detect a quench and safely extract the energy stored in the circuits (about 1GJ only in one of the dipole circuits) after a resistive transition. Besides, in such complex architecture, many technical services (e.g. cooling and ventilation, technical network, electrical distribution, GSM network, controls system, etc.) have to be reliably available during commissioning. Consequently, the commissioning of the technical systems and the associated infrastructures has been carefully studied. Procedures, automatic control and analysis tools, repositories for test data, management structures for carrying out and following up the tests have been put in place. This paper briefly describes the management structure and the tools created to ensure safe, smooth and rapid commissioning.  
 
MOPC137 The Cryogenic Storage Ring Project at Heidelberg ion, vacuum, storage-ring, electron 394
 
  • R. von Hahn, K. Blaum, J. R. Crespo López-Urrutia, M. W. Froese, M. Grieser, M. Lange, F. Laux, S. Menk, D. Orlov, R. Repnow, C. D. Schroeter, D. Schwalm, T. Sieber, J. Ullrich, J. Varju, A. Wolf
    MPI-K, Heidelberg
  • H. Quack
    TU Dresden, Dresden
  • M. Rappaport, D. Zajfman
    Weizmann Institute of Science, Physics, Rehovot
  • X. Urbain
    UCL CRC, Louvain-la-Neuve
  At the Max-Planck-Institut für Kernphysik in Heidelberg a next generation electrostatic storage ring at cryogenic temperatures is under development. The main perspective of this unique cryogenic storage ring (CSR) is the research on ions, molecules and clusters up to bio molecules in the energy range of 20 keV -300 keV at low temperatures down to 2 Kelvin. The achievement of this low temperature for all material walls seen by the ions in the storage ring not only causes a strong reduction of black body radiation incident onto the stored particles, but also acts as a large cryopump, expected to achieve a vacuum of better than 1·10-15 mbar (corresponding to 1·10-13 mbar room temperature äquivalent). The low temperature and the extreme low vacuum will allow novel experiments to be performed, such as rotational and vibrational state control of molecular ions and their interaction with ultra-low energy electrons and laser radiation. A 20 W at 2 K refrigerator was designed and successfully commissioned. A connection with the fully assembled cryogenic prototype ion trap is under way. In this paper the concept and the status of the cryogenic storage ring will be presented.  
 
MOPD002 Fabrication of ILC Prototype Cavities at Advanced Energy Systems, Inc. controls, vacuum, target, site 448
 
  • A. J. Favale, M. D. Cole, E. Peterson, J. Rathke
    AES, Medford, NY
  Advanced Energy Systems, Inc. has recently completed manufacture of four standard 9-cell TESLA-style ILC cavities, six single-cell ILC prototype cavities, six 9-cell symmetric ILC cavities, and one 9-cell re-entrant cavity of the Cornell design. This paper will present an overview of these fabrication projects and of the evolution of AES capability in cavity manufacturing. To date four of the 9-cell ILC cavities have been tested, the six single-cell cavities have been tested, and the 9-cell reentrant cavity has been tested. Preliminary results will be shown.  
 
MOPD005 Recent Activities in ILC R&D at Hitachi vacuum, superconducting-RF, radiation, insertion 457
 
  • T. Semba, Y. Itou, S. Kajiura, Y. Tsujioka, T. Yoshinari
    Hitachi Ltd., Ibaraki-ken
  • M. Abe
    Hitachi, Ltd., Power & Industrial Systems R&D Laboratory, Ibaraki-ken
  • H. Hayano, Y. Higashi, S. Noguchi, N. Ohuchi, K. Saito, K. Tsuchiya
    KEK, Ibaraki
  • N. Torii
    Hitachi High-Technologies Corp., Ibaraki-ken
  We participated in the construction of STF (Superconducting RF Test Facility) cryomodule. This paper describes our recent activities in ILC R&D.  
 
MOPD014 First Test Results of ILC/STF Cryogenic System at KEK superconducting-RF, booster, vacuum, linear-collider 472
 
  • S. Kaneda, T. Ichitani
    Taiyo Nippon Sanso Corporation, Kawasaki-city Kanagawa Pref.
  • K. Hara, K. Hosoyama, A. Kabe, Y. Kojima, H. Nakai, K. Nakanishi
    KEK, Ibaraki
  • T. Kanekiyo
    Hitachi Technologies and Services Co., Ltd., Kandatsu, Tsuchiura
  • M. Noguchi
    Mayekawa MFG. Co., Ltd., Moriya
  • S. Sakuma, K. Suzuki
    Taiyo Nippon Sanso Higashikanto Corporation, Hitachi-city, Ibaraki-Pref
  • J. Yoshida
    Hitachi Plant Technologies, Ltd., Tokyo
  The STF (Superconducting RF Test Facility) cryogenic system, of which capacity is 30W at 2.0K, has been constructed and commissioned for testing STF cryomodule. In the first operation phase, the STF cryogenic system was successfully cooled down to maintain a superconducting RF cavity at the working temperature of 2.0K. Presented in this session will be the results of the first operation of the cryogenic system and the future collaboration plan among KEK and Japanese cryogenic industrial members.  
 
MOPD022 New 1MW 704MHz RF Test Stand at CEA-Saclay klystron, cathode, linac, proton 490
 
  • S. Chel, M. Desmons, A. Hamdi, F. Peauger
    CEA, Gif-sur-Yvette
  In the frame of the european CARE/HIPPI programme, superconducting accelerating cavities for pulsed proton injectors are developed. Qualification of these 704 MHz RF structures fully equipped (housed in a helium tank, with tuning system and power coupler), requires to perform high power tests in the existing horizontal cryostat CryHoLab. During the last years, CEA-Saclay built and ordered the necessary RF equipments to make such a platform for high power RF tests in a cryogenic environment available to the partners in HIPPI and later on to any other interested European teams. The main components of the RF test stand (95 kV-275kVA DC High Voltage Power Supply, 50Hz modulator and 1MW 704.4MHz RF klystron amplifier) are now installed and tested. In this paper, we present the different components with a focus on the new design of the hard tube modulator to match the new specifications and the compatibility with the floating HVPS, the results of the HV and RF measurements performed and we give a brief description of the PXI-based controller for the interlocks and klystron auxiliary controls.  
 
MOPP114 Design of the Prototypical Cryomodule for the EUROTRANS Superconducting Linac for Nuclear Waste Transmutation linac, vacuum, radiation, alignment 826
 
  • S. Barbanotti, N. Panzeri, P. Pierini
    INFN/LASA, Segrate (MI)
  • J.-L. Biarrotte, P. Blache, C. Commeaux, P. Duthil, E. Rampnoux
    IPN, Orsay
  • M. Souli
    GANIL, Caen
  One task of the accelerator workpackage of the EUROTRANS program for the design of a nuclear waste transmutation system is dedicated to the engineering and realization of a prototype cryomodule of the high energy section of the linac, equipped with elliptical superconducting niobium cavities. We review here the present status of the design and the planned program that foresees the experimental characterization of the fully equipped cavity and RF system under its nominal operating conditions.  
 
MOPP115 Production and Qualification of Low Thermal Conduction Suspension Supports for the Cold Mass of Long Superconducting Acceleration Modules radiation, simulation, site, controls 829
 
  • S. Barbanotti, M. Bonezzi, M. Todero
    INFN/LASA, Segrate (MI)
  • C. Engling, K. Jensch, R. Mattusch
    DESY, Hamburg
  A post is an assembly of a low thermal conduction composite material pipe (fiberglass pipe) and some shrink-fit aluminum and steel discs and rings, designed to provide a mechanical support and a thermal insulation to the cold mass of the long cryomodules of the TTF, which are foreseen also for the XFEL and ILC. We review here the production, testing and qualification for the production of post supports, which have been successfully provided for the cryomodules of the TTF in DESY, the STF in KEK and ILCTA in FNAL.  
 
MOPP117 First Test of the Cornell Single-cavity Horizontal Cryomodule linac, radiation, vacuum, resonance 835
 
  • S. A. Belomestnykh, E. P. Chojnacki, R. Ehrlich, R. P.K. Kaplan, M. Liepe, V. Medjidzade, D. Meidlinger, H. Padamsee, P. Quigley, J. J. Reilly, D. M. Sabol, J. Sears, V. D. Shemelin, E. N. Smith, V. Veshcherevich, D. Widger
    CLASSE, Ithaca
  A single-cavity horizontal test cryomodule (HTC) has been designed and fabricated recently at Cornell University for ERL project. This cryomodule is a shortened version of the full injector cryomodule, which will house five superconducting cavities. It serves as a test bench for new design features and for testing fully dressed two-cell ERL injector cavities. The cryostat design has been optimized for precise cavity alignment, good magnetic shielding, and high cryogenic loads from the RF cavities, input couplers, and HOM loads. The HTC was made long enough so in the future it can accommodate longer, multicell cavities of the ERL main linac. In this paper we report on results from the first full test of the HTC, including RF system and superconducting cavity performance, cryomodule studies and operation of a new 1.8 K cryogenic system.  
 
MOPP120 Full Characterization of the Piezo Blade Tuner for Superconducting RF Cavities insertion, controls, feedback, superconducting-RF 838
 
  • A. Bosotti, C. Pagani, N. Panzeri, R. Paparella
    INFN/LASA, Segrate (MI)
  • C. Albrecht, K. Jensch, R. Lange, L. Lilje
    DESY, Hamburg
  • J. Knobloch, O. Kugeler, A. Neumann
    BESSY GmbH, Berlin
  Cavity tuners are mechanical devices designed to precisely match the resonant frequency of the superconducting (SC) cavity to the RF frequency synchronous with the beam. The blade tuner is mounted coaxially to the cavity and changes the resonator frequency by varying its length. A high tuning range is desired together with small mechanical hysteresis, to allow easy and reproducible resonator setup operations. High stiffness is also demanded to the tuner system both to ensure mechanical stability and to mitigate the frequency instabilities induced by perturbations. In high gradient SC resonators, the main sources of resonant frequency instability are the Lorentz Force Detuning (LFD) under pulsed mode operation, and the microphonic noise, in continuous wave (CW) with high loaded quality factors. Piezoceramic elements add dynamic tuning capabilities to the system, allowing fast compensation of these instabilities with the help of feed-forward and feedback loops. The piezo blade tuner has been extensively tested both at room temperature and at cold once assembled on a TESLA type cavity in its final configuration. This paper presents the summary of the complete characterization tests.  
 
MOPP124 Commissioning of the 400 MHz LHC RF System klystron, feedback, controls, vacuum 847
 
  • E. Ciapala, L. Arnaudon, P. Baudrenghien, O. Brunner, A. Butterworth, T. P.R. Linnecar, P. Maesen, J. C. Molendijk, E. Montesinos, D. Valuch, F. Weierud
    CERN, Geneva
  The installation of the 400 MHz superconducting RF system in LHC is finished and commissioning is under way. The final RF system comprises four cryomodules each with four cavities in the LHC tunnel. Also underground in an adjacent cavern shielded from the main tunnel are the sixteen 300 kW klystron RF power sources with their high voltage bunkers, two Faraday cages containing RF feedback and beam control electronics, and racks containing all the slow controls. The system and the experience gained during commissioning will be described. In particular, results from conditioning the cavities and their movable main power couplers and the setting up of the low level RF feedbacks will be presented.  
 
MOPP125 A Superconducting RF Vertical Test Facility at Daresbury Laboratory radiation, shielding, superconducting-RF, controls 850
 
  • P. A. Corlett, R. Bate, C. D. Beard, B. D. Fell, P. Goudket, S. M. Pattalwar
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
  • P. K. Ambattu, G. Burt, A. C. Dexter, M. I. Tahir
    Cockcroft Institute, Lancaster University, Lancaster
  A superconducting RF vertical test facility (VTF) has been constructed at Daresbury Laboratory for the testing of superconducting RF cavities at 2K. When fully operational, the facility will be capable of testing a 9-cell 1.3 GHz Tesla type cavity. The facility is initially to be configured to perform phase synchronisation experiments between a pair of single cell 3.9GHz ILC crab cavities. These experiments require the cavities to operate at the same frequency; therefore a tuning mechanism has been integrated into the system. The system is described, and data from the initial operation of the facility is presented.  
 
MOPP136 Performance of Single Crystal Niobium Cavities electron, resonance 877
 
  • P. Kneisel, G. Ciovati
    Jefferson Lab, Newport News, Virginia
  • A. Brinkmann, D. Reschke, W. Singer, X. Singer
    DESY, Hamburg
  We have fabricated and tested a total of six single cell niobium cavities, made from single crystal, high purity niobium. Two of the three cavities of the TESLA shape (1300 MHz) were made from Heraeus niobium by extending a smaller single crystals by rolling and annealing steps; the third cavity was made by spinning. The three other cavities of the scaled LL shape (2) and TESLA shape (1) resonated at 2.3 GHz and were fabricated from “as received” single crystals, both from Heraeus and CBMM niobium. After appropriate surface treatments by buffered chemical polishing and electropolishing all cavities performed quite nicely and peak surface magnetic fields of ~ 160 mT or above corresponding to accelerating gradients between 38 MV/m and 45 MV/m were reached. This paper reports about the performance of these cavities.  
 
MOPP144 The First Cool-down Tests of the 6 Meter-Long-Cryomodules for Superconducting RF Test Facility (STF) at KEK superconducting-RF, vacuum, linear-collider, collider 892
 
  • N. Ohuchi, F. Furuta, K. Hara, H. Hayano, N. Higashi, Y. Higashi, H. Hisamatsu, K. Hosoyama, E. Kako, Y. Kojima, M. Masuzawa, H. Matsumoto, H. Nakai, S. Noguchi, T. Saeki, K. Saito, T. Shishido, A. Terashima, N. Toge, K. Tsuchiya, K. Yokoya
    KEK, Ibaraki
  • M. H. Tsai
    NSRRC, Hsinchu
  • Q. J. Xu
    IHEP Beijing, Beijing
  KEK is presently constructing the Superconducting RF Test Facility (STF) as the center of the ILC-R&D in Asia from 2005. In this project, KEK aims to get the manufacturing and operational experiences of the RF cavity and cryomodule toward the ILC, and two cryomodules have been developed. These cryomodules are 6 meter long and have 4 nine-cell cavities in each cryostat. The basic cross section designs of the cryomodules are almost same as the design of TESLA type-III, however, each cryostat has the different type of cavities, TESLA type and Low-Loss type. The tests for the cryomodules are planed to be performed at three steps. In the first test, measurements of the cryogenic performances of these cryomodules are the main objective. One nine-cell cavity was assembled in each cryostat and the cool-down of the two cryomodules was performed. In the following tests, the four nine-cell cavities will be assembled in each cryostat as the complete integration and the beam test will be performed. In this paper, we will report the design of the cryomodules and the cryogenic performances at the first cold test.  
 
MOPP146 The Coaxial Tuner for ILCTA_NML at Fermilab superconductivity, vacuum, linear-collider, collider 895
 
  • A. Bosotti, C. Pagani, N. Panzeri, R. Paparella
    INFN/LASA, Segrate (MI)
  The piezo Blade Tuner prototype has been successfully tested inside the horizontal cryostat, CHECHIA, at DESY and extensive tests at BESSY are planned. As suggested by the cold test results, a few minor modifications have been implemented and a set of 8 improved devices is under construction for the installation in the second module of ILCTA at Fermilab. This reviewed design, together with a simplified helium tank in prototyping, should hopefully fulfill also the XFEL requests in term of performances and cost. In particular the use of thicker blades and their slightly different distribution along the circumference produces the increase of the tuner strength and stiffness that is needed in order to fulfill the pressure vessel regulations for qualification. As in the past, two equivalent devices, respectively in titanium and stainless steel, have been designed to maintain open the possibility of the use of a SS helium vessel once the required technology were developed. The results of the extensive mechanical tests performed to validate the estimated performances and life time are also presented.  
 
MOPP149 Recent Developments of the Superconducting CH-Cavities simulation, beam-losses, linac, resonance 901
 
  • H. Podlech, A. Bechtold, M. Busch, F. Dziuba, H. Liebermann, U. Ratzinger
    IAP, Frankfurt am Main
  The Crossbar-H-mode (CH)-structure which has been developed at the IAP in Frankfurt is a multi-cell drift tube structure for the efficient acceleration of low and medium energy protons and ions. The superconducting low energy CH-prototype cavity has reached gradients of up to 7 MV/m, corresponding to an effective voltage gain of 5.6 MV. This shows that high real estate gradients can be achieved in superconducting low energy multi-cell cavities. Additionally, microphonics and tuning measurements have been performed at room temperature and at 4K. Optimized cavity geometry for high power beam projects and plans for the construction of a new superconducting cavity will be presented.  
 
MOPP165 FZJ Smallest SC Triple-Spoke Cavity vacuum, coupling, simulation, site 937
 
  • E. Zaplatin, W. Braeutigam, M. Pap, M. Skrobucha
    FZJ, Jülich
  • P. Kneisel
    Jefferson Lab, Newport News, Virginia
  The paper describes the design, fabrication and test results of the smallest triple-spoke cavity (resonant frequency 760 MHz, β=0.2) developed at Forschungszentrum Juelich.  
 
MOPP168 Tests on the 1.3 GHz Low Loss Single-Cell RF Superconducting Large Grain Cavities of IHEP linear-collider, linac, vacuum, collider 943
 
  • Z. G. Zong, J. Gao, M. Q. Ge, J. Gu, H. Sun, D. Wang, Q. J. Xu, J. Y. Zhai, F. C. Zhao
    IHEP Beijing, Beijing
  • F. Furuta, T. Saeki, K. Saito
    KEK, Ibaraki
  • L. Q. Liu
    Technical Institute of Physics and Chemistry, Beijing
  • L.-Y. Xiong, L. Zhang, T. X. Zhao, Z. G. Zong
    TIPC, BeiJing
  To contribute to the International Linear Collider (ILC) R&D on the 1.3 GHz low loss cavities has been carried out at IHEP since 2005. Six cavities had been fabricated by the standard technology and treated by some procedures of surface treatments, such as centrifugal barrel polishing, barrel chemical polishing, annealing, high pressure rinsing and baking at in-house IHEP. Because of the shortage of liquid helium in Beijing two large grain cavities with a fine grain one were sent to KEK for vertical tests. The large grain cavities was tested and treated at KEk and finally both reached the accelerating gradients of more than 35 MV/m with the maximum of 40.27 MV/m. This paper presents the testing and results of the large grain cavities.  
 
TUPC041 Design of Cold BPM Feedthrough simulation, resonance, insertion, impedance 1146
 
  • K. Iwamoto, Y. Ikeda
    KFG, NEUSS
  • T. Kitamura, T. Matsuoka
    KYOCERA Corporation, Higashiomi-city, Shiga
  We have designed many BPM feedthrough used metallized ceramic components. We select the best material of ceramic and metal ajusted for magnetism and the material of chamber. The request for accelerator application that low temperature and RF property has increased in recent years. In this presentation,we report on the design of the BPM feedthrough for low temperature and for the RF up to 20GHz. We appreciated the bonding strength for ceramic and metal in low temperature 4K,77K. Mo/Mn metallised ceramic is brazed between Fe-Ni-Co Alloy metal components using Ag-Cu brazing material. Ceramic is 99% Alumina which is commonly used for UHV application. The tensile strength in low temperature is lower than in R. T.approximately 10%, but the dispersion affected by brazing flow condition is bigger than this temperature effect. The influence of low temperature is less than brazing flow condition, therefore the bonding strength of metallised ceramic is enough for UHV application at 4K.  
 
TUPC055 Operating MCP Detectors at Cryogenic Temperatures vacuum, electron, storage-ring, ion 1179
 
  • K.-U. Kuehnel, C. D. Schroeter, J. Ullrich
    MPI-K, Heidelberg
  At present, a low energy electrostatic storage ring operating at cryogenic temperatures down to 2 K is being build up at the MPI-K in Heidelberg. Both, beam diagnostics and experiments rely on the use of position sensitive micro-channel plate (MCP) detectors equipped with phosphor screens or delay line anodes. Since little is known about the performance of these detector types in a cryogenic environment a test chamber was built to investigate their properties. A delay line MCP detector was successfully tested at temperatures as low as 25 K. In this contribution the detailed results of theses tests as well as possible applications of the detector are presented.  
 
TUPC125 Status of the Spallation Neutron Source Superconducting RF Facility vacuum, controls, radiation, superconducting-RF 1362
 
  • F. Casagrande, S. Assadi, M. T. Crofford, W. R. DeVan, X. Geng, T. W. Hardek, S. Henderson, M. P. Howell, Y. W. Kang, J. Mammosser, W. C. Stone, D. Stout, W. H. Strong, D. C. Williams, P. A. Wright
    ORNL, Oak Ridge, Tennessee
  The Spallation Neutron Source (SNS) project was completed without on-site superconducting RF (SRF) facilities. Installation of the infrastructure necessary to maintain and repair the superconducting Linac and to support power upgrade research and development (R&D) is well underway. Installation of a Class10/100/10,000 cleanroom and outfitting of the test cave with RF, vacuum, controls, personnel protection and cryogenics systems is now complete. These systems were recently operated satisfactorily to test a cryomodule that had been removed from the accelerator and repaired in the cleanroom. A horizontal cryostat has been fabricated and will be soon commissioned. Equipment for cryomodule assembly and disassembly has been installed and used for cryomodule disassembly. Cavity processing equipment, specifically an ultra-pure water system, high pressure rinse system, and vertical test area is being designed and installed. This effort is providing both high-power test capability as well as long-term maintenance capabilities. This paper presents the current status and the future plans for the SNS SRF test facility.  
 
TUPD019 Inter-disciplinary Mechanical and Architectural 3D CAD Design Process at the European XFEL controls, simulation, civil-engineering, feedback 1467
 
  • L. Hagge, N. Bergel, T. H. Hott, J. Kreutzkamp, S. Suehl, N. Welle
    DESY, Hamburg
  Realising the European-XFEL involves creating and coordinating several types of 3D design models for many different subsystems like underground buildings, utilities, accelerator systems or photon beam lines. In order to handle the huge amount of data, reduced envelope models are needed for integrating the subsystems towards the complete facility and to ensure that the different subsystems connect properly and do not intersect. Detailed component design models are required for planning approval, tendering or in-house production. A key issue was to develop an optimized design for the facilities while still being able to accommodate possible late R&D-driven design changes of subsystems. The paper describes the procedures and tools which are used for planning and designing the European-XFEL and reports benefits and experience. The procedures in use allow visualization of the facilities, negotiation of requirements and solutions between all the working groups, optimized storing of the documentation as well as running approval and change management procedures. Tools in use include a requirements database, 3D-CAD systems and an engineering data management system.  
 
TUPD021 Sliding Force Measurements on the LHC RF Contact Plug in Modules at 15 K and in UHV vacuum, impedance 1473
 
  • K. Artoos, M. Guinchard, T. Renaglia
    CERN, Geneva
  Some sliding RF contacts mounted in the Plug In Modules in the LHC interconnects failed during a thermal cycle between 4.2 K and room temperature. Gold-coated copper-beryllium RF fingers buckled during the warm up of the machine, indicating that one or more parameters during operation (e.g., the friction coefficient under vacuum) might be different from what was used in the calculations. This report describes the measurement of the longitudinal forces acting on the sliding RF fingers at operating vacuum and temperatures.  
 
TUPP068 Bench Measurements of the Low Frequency Transverse Impedance of the CERN LHC Beam Vacuum Interconnects with RF Contacts impedance, vacuum, coupling, betatron 1697
 
  • B. Salvant
    EPFL, Lausanne
  • F. Caspers, E. Métral
    CERN, Geneva
  • F. Roncarolo
    UMAN, Manchester
  The low frequency longitudinal and transverse impedances of the CERN Large Hadron Collider (LHC) have to be specifically minimized to prevent the onset of coherent instabilities. The LHC beam vacuum interconnects were designed as Plug In Modules (PIMs) with RF contacts to reduce their coupling impedances, but the resulting contact resistance is a concern, as this effect is difficult to estimate. High sensitivity measurements of the transverse impedance of a PIM at low frequency using a coil probe are presented. In particular, the increase of the transverse impedance of the PIM when it is elongated to its operating position is discussed in detail. Finally, the issue of non-conforming contact resistance is also addressed.  
 
TUPP110 Rotative Systems for Dose Distribution in Hadrontherapy (Gantries) dipole, ion, superconducting-magnet, proton 1779
 
  • M. J. Bajard
    UCBL, Villeurbanne
  • F. A. Kircher
    CEA, Grenoble
  Tumour treatments with high velocity ion beams or protons are characterised by a great depth precision (Bragg pic) and a low divergence for dose delivery in very small volumes. In order to spare normal tissues before and around the tumour it is necessary to have the choice of the beam incidence because the patient cannot be moved. Different devices have been built mainly exocentric and isocentric. Many others are being studied. Cryogenic solutions are analysed to reduce the total mass in rotation. For example it would be very interesting to choose a superconductive solution for the last 90° dipole.  
 
TUPP160 Superconducting RF Activities at ACCEL Instruments storage-ring, controls, damping, superconducting-RF 1884
 
  • M. Pekeler, S. Bauer, P. vom Stein
    ACCEL, Bergisch Gladbach
  We report on highlights of SRF activities at ACCEL Instruments during the last few years. For example the development of a new hydrofloric and sulphoric acid free electropolishing method for niobium cavities and the construction and installation of a new standard electropolishing plant for 9-cell 1.3 GHz cavities. In addition we have further developed our design for 500 MHz superconducting RF modules for light sources and delivered three such accelerator modules for Shanghai Ligth Source. For SOLEIL we manufactured a 350 MHz twin cavity accelerator module using the technology of sputtering niobium onto copper.  
 
WEOBM04 LHC: The World's Largest Vacuum Systems being Commissioned at CERN vacuum, ion, injection, cathode 1959
 
  • J. M. Jimenez
    CERN, Geneva
  When it switches on in the spring of 2008, the 26.7 km Large Hadron Collider (LHC) at CERN, will have the world's largest vacuum system operating over a wide range of pressures and employing an impressive array of vacuum technologies. This system is composed by 54 km of UHV vacuum for the circulating beams and 24 km of insulation vacuum around the cryogenic magnets operated mainly at 1.9 K. Over the 54 km of UHV beam vacuum, 48 km of this must be at cryogenic temperature (1.9 K). The remaining 6 km of beam vacuum containing the insertions is at ambient temperature and uses non-evaporable getter (NEG) coatings – a vacuum technology that was born and industrialized at CERN. The pumping is completed using 600 ion pumps to remove noble gases and 1000 gauges are used to monitor the pressures. The cryogenic insulation vacuum, while technically less demanding, is impressive by its size - 24 km in length, 900 mm in diameter for a total volume of 640 m3. Once cooled at 1.9 K, the cryogenic pumping allows reaching pressure in the 10-6 mbar range. This paper described the entire vacuum system and the challenges of the design, manufacturing, installation and commissioning phases.  
slides icon Slides  
 
WEPC022 Operation and Recent Developments at the ESRF feedback, undulator, storage-ring, lattice 2028
 
  • J.-L. Revol, J. C. Biasci, J-F. B. Bouteille, J. M. Chaize, J. Chavanne, P. Elleaume, L. Farvacque, G. Gautier, L. Goirand, M. Hahn, L. Hardy, J. Jacob, R. Kersevan, J. M. Koch, J. M. Mercier, I. Parat, C. Penel, T. P. Perron, E. Plouviez, A. Ropert, K. B. Scheidt, D. Schmied, V. Serriere
    ESRF, Grenoble
  The ESRF has been operating for a period close to fifteen years and is now looking towards an ambitious upgrade programme for the coming ten years. This paper reports on the performances achieved today with the ESRF storage ring, as well as developments accomplished and projects underway. These include a new filling mode for pump and probe experiments, the evolution of insertion devices, developments to improve beam stability, in particular transverse and longitudinal multibunch feedbacks, and the current increase from 200 to 300 mA. The upgrade of the lattice to accommodate longer straight sections and the new High Quality Power Supply system will also be presented. The machine reliability and the most important failures will be discussed. Finally, the use of an electronic logbook in routine operation will be presented, and the status on the control system including TANGO collaboration given.  
 
WEPC098 Development of Cryogenic Undulator CPMU at SOLEIL permanent-magnet, undulator, vacuum, radiation 2225
 
  • C. Benabderrahmane, P. Berteaud, N. Béchu, M.-E. Couprie, J.-M. Filhol, C. Herbeaux, C. A. Kitegi, J. L. Marlats, A. Mary, K. Tavakoli
    SOLEIL, Gif-sur-Yvette
  On SOLEIL at 2.75 GeV, producing hard X rays requires short period and small gap in-vacuum hybrid permanent magnet undulators. Besides, higher achieved peak magnetic field can be while operating at cryogenic temperature Tc (around 140 K). When cooling down the permanent magnets, the remanence Br increases down to a certain temperature at which the process is limited by the appearance of the Spin Reorientation Transition phenomenon. The coercivity is also increased at Tc which improves significantly the resistance to radiation. R&D studies, aims at replacing SmCo by NdFeB permanent magnets whose Br of 1.4 T, could enable to increase at least by 30% the peak magnetic field at Tc. Unfortunately such magnet grade can’t be heated to high temperature without degrading the magnetic properties, which limits the residual pressure that can be achieved. Temperature gradient and mechanical deformation are also technical issues. Different permanent magnet grades at Tc are characterized. Studies are also carried out on a small assembly of four periods. Residual pressures obtained with or without partial baking on standard U20 in-vacuum undulators are compared.  
 
WEPC105 Construction of a Cryogenic Permanent Magnet Undulator at ESRF undulator, vacuum, simulation, laser 2243
 
  • J. Chavanne, M. Hahn, R. Kersevan, C. A. Kitegi, C. Penel, F. Revol
    ESRF, Grenoble
  A cryogenic permanent magnet undulator (CPMU) has been constructed at ESRF. The device is a full scale in-vacuum undulator with a magnetic length of 2 metres and a period of 18 mm. This prototype is still compatible with an operation at room temperature, it has been mainly used to investigate the technological issues connected to the operation at low temperature. An important effort has been dedicated to the construction of a complete measuring bench operated in-vacuum with the undulator at cryogenic temperatures around 150 K. The bench includes a stretched wire system for field integral measurement and a local field measurement assembly suitable for the accurate characterization of the optical phase error along the undulator. The main results of the magnetic measurements will be presented , they confirm the simulations performed with RADIA using NdFeB permanent magnet material models at low temperature. The cryogenic system used to cool the undulator is based on a reliable liquid nitrogen closed loop. The heat budget of the device will be discussed. The prototype has been installed on the ESRF ring in December 2007. The first results of operation will be presented.  
 
WEPD006 Conceptual Design of Superferric Magnets for PS2 dipole, quadrupole, magnet-design, injection 2410
 
  • L. Bottura, G. De Rijk, M. Karppinen, G. Kirby, R. Maccaferri, C. Maglioni, V. Parma, L. Rossi, W. Scandale, L. Serio, D. Tommasini
    CERN, Geneva
  We analyze feasibility and cost of a superferric magnet design for the PS2, the novel 50 GeV ring that should replace the PS in the CERN injector chain. Specifically, we provide the conceptual design of dipole and quadrupoles, including considerations on cryogenics and powering. The magnets have warm iron yoke, and cryostated superconducting coils embedded in the magnet, which reduces AC loss at cryogenic temperature. The superconductor has large operating margin to endure beam loss and operating loads over a long period of time. Although conservative, and without any critical dependence on novel technology developments, this superconducting option appears to be attractive as a low-power alternative to the normal-conducting magnets that are the present baseline for the PS2 design. In addition it provides flexibility in the selection of flat-top duration at no additional cost.  
 
WEPD007 Detection and Location of Electrical Insulation Faults on the LHC Superconducting Circuits during the Hardware Commissioning pick-up, diagnostics, instrumentation, quadrupole 2413
 
  • D. Bozzini, V. Chareyre, K. H. Mess, S. Russenschuck
    CERN, Geneva
  As part of the electrical quality assurance program, all superconducting circuits of the LHC have to be subjected to a (high) DC voltage, up to 1.9 kV DC, for the testing of the electrical insulation. Circuits with an insulation fault have to be repaired before powering. Fault location within a ± 3 m range over the total length of 2700 m has been achieved in order to limit the number of interconnection openings. In this paper, the methods, tooling, and procedures for the detection and location of electrical faults will be presented in view of the practical experience gained in the LHC tunnel. Three cases of faults detected and localized during the hardware commissioning phases of the LHC will be discussed.  
 
WEPD008 Automatic System for the DC High Voltage Qualification of the Superconducting Electrical Circuits of the LHC Machine controls, monitoring, power-supply, dipole 2416
 
  • D. Bozzini, V. Chareyre, S. Russenschuck
    CERN, Geneva
  • M. Bednarek, P. Jurkiewicz, A. Kotarba, J. Ludwin, S. Olek
    HNINP, Kraków
  A system has been developed to verify automatically with the application of a DC high voltage, the insulation resistance between circuits to circuit and circuit to ground. In the most complex case of the LHC machine up to 72 circuits share the same volume inside the cryogenic lines and each circuit can have an insulation fault versus any other circuit or versus ground. The system can connect up to 80 circuits and apply a voltage up to 2 kV DC. The leakage of current flowing through each circuit is measured within a range of 1 nA to 2 mA. The matrix of measurements characterizes the paths taken by the currents and recognizes weak points of the insulation between circuits. The system is composed of a DC voltage source, a data acquisition card that measures with precision currents and voltages and drives up to 5 high voltage switching modules offering each 16 channels. A LabVIEW based application controls the system for an automatic and safe operation. This paper describes the hardware and software design, the testing methodology and the results obtained during the qualification of the LHC superconducting circuits.  
 
WEPD012 The LHC Continuous Cryostat Interconnections: the Organization of a Logistically Complex Worksite Requiring Strict Quality Standards and High Output controls, vacuum, quadrupole, alignment 2428
 
  • P. Fessia, F. F. Bertinelli, D. Bozzini, P. Cruikshank, A. Jacquemod, W. Maan, A. Musso, L. Oberli, A. Poncet, S. Russenschuck, F. Savary, M. Struik, Z. Sulek, J.-P. G. Tock, D. Tommasini, C. Vollinger
    CERN, Geneva
  • A. Grimaud
    ALL43, Saint-Genis-Pouilly
  • A. Kotarba
    HNINP, Kraków
  • L. Vaudaux
    IEG, St-Genis-Pouilly
  The interconnections of the Large Hadron Collider (LHC) continuous cryostat have been completed in autumn 2007: 1695 magnet to magnet interconnections and 224 interconnections between the continuous cryostat and the cryogenic distribution line have been closed along the 27km of the LHC. The high productivity demanded, the complexity of the interconnection sequence, the strict quality standards have required an ad hoc organization in order to steer and coordinate the activities on a worksite that was spread along the whole accelerator ring. The optimization of the intricate sequence of construction and test phases carried out by CERN staff, CERN collaborating institutes and contractors have led to the necessity of a common approach and of a very effective information flow. Specialized CERN teams have been created to deal with non standard operation to smooth the work sequences of the main assembly teams. In this paper, after having recalled the main technical challenges, we review the organizational choices that have been taken, their impact on quality and productivity and we briefly analyze the development of the worksite in term of allocated resources and production.  
 
WEPD016 Electrical Quality Assurance of the Superconducting Circuits during LHC Machine Assembly dipole, pick-up, controls, quadrupole 2440
 
  • S. Russenschuck, D. Bozzini, V. Chareyre, O. Desebe, K. H. Mess
    CERN, Geneva
  • M. Bednarek, D. P. Dworak, E. Gornicki, P. Jurkiewicz, P. J. Kapusta, A. Kotarba, J. Ludwin, S. Olek, M. Talach, M. Zieblinski
    HNINP, Kraków
  • M. Klisch, B. Prochal
    AGH, Cracow
  Based on the LHC powering reference database, all-together 1712 superconducting circuits have been electrically wired and interconnected in the various cryogenic lines of the LHC machine. Continuity, magnet polarity, and the quality of the electrical insulation have been the main objectives of the Electrical Quality Assurance (ELQA) activities during the LHC machine assembly. Another activity aimed at ensuring the coherence between the reference database on one side, and the polarity conventions used for beam simulation and magnetic measurements. With the assembly of the LHC now completed, the paper reviews the methods and procedures established for the ELQA, as well as the employed time and resources. The qualification results will be presented with the emphasis on the detected electrical non-conformities and their possible impact on the performance of the LHC machine.  
 
WEPD018 Commissioning of the LHC Current Leads dipole, quadrupole, controls, instrumentation 2446
 
  • A. Ballarino, S. A. March, K. H. Mess
    CERN, Geneva
  The powering of the LHC superconducting magnets relies on more than 3000 leads transporting the current from/to the cryogenic environment and rated at currents ranging from 60 A to 13000 A. The design of these leads, about 1000 of which are based on high temperature superconducting material, was entirely done at CERN, where prototype assemblies were also assembled and tested, while the series production was done in external laboratory and companies on the basis of build-to-print specification. This report summarizes the results of the tests performed during the commissioning of the LHC machine, when the leads underwent the thermal and electrical cycles necessary for the powering of the LHC superconducting circuits.  
 
WEPD020 Stability of Superconducting Wire in Magnetic Field superconducting-magnet, power-supply, dipole 2449
 
  • K. Ruwali
    GUAS/AS, Ibaraki
  • K. Hosoyama, K. Nakanishi
    KEK, Ibaraki
  • Y. Teramoto, A. Yamanaka
    Toyobo Research Institute, Shiga
  Main cause of premature quench in superconducting magnet is the heat generated due to superconducting wire motion. The wire motion occurs where electromagnetic force to conductors exceeds frictional force on surfaces of the conductors. Hence, frictional properties of the conductors and winding structures are important parameters for characterizing stability of the superconducting windings. An experimental setup was prepared to detect wire movement by observing spike in voltage of the superconducting sample wire. A detailed study was carried out in order to study superconducting wire motion under different experimental conditions such as varying applied load to specimen wire, back up field, varying the interface of superconductor and base material. The base materials used are polyimide film and Dyneema. The Dyneema has low frictional coefficient and negative thermal expansion. In the case of Dyneema, it is found that amplitude of voltage generated due to wire motion reduces and also relatively smooth motion of wire is observed. These effects are attributed to the low frictional coefficient. The experimental observation will be discussed in detail.  
 
WEPD026 The Special LHC Interconnections: Technologies, Organization and Quality Control insertion, controls, vacuum, superconducting-magnet 2464
 
  • J.-P. G. Tock, F. F. Bertinelli, D. Bozzini, P. Cruikshank, O. Desebe, M. F. Felip-Hernando, C. Garion, A. Jacquemod, N. Kos, F. Laurent, A. Poncet, S. Russenschuck, I. Slits, L. R. Williams
    CERN, Geneva
  • L. Hajduk
    HNINP, Krakow
  • L. Vaudaux
    IEG, St-Genis-Pouilly
  In addition to the standard interconnections of the continuous cryostat of the Large Hadron Collider (LHC), there exists a variety of special ones related to specific components and assemblies, such as cryomagnets of the insertion regions, electrical feedboxes and superconducting links. Though they are less numerous, their specificities created many additional interconnection types, requiring a larger variety of assembly operations and quality control techniques, keeping very high standards of quality. Considerable flexibility and adaptability from all the teams involved (CERN staff, collaborating institutes, contractors) were the key points to ensure the success of this task. This paper first describes the special interconnections and presents the employed technologies which are adapted from the standard work. Then, the organization adopted for this non-repetitive work is described. Examples of non-conformities that were resolved are also discussed. Figures of merit in terms of quality and productivity are given and compared with standard interconnections work.  
 
WEPD028 Performance of the Superconducting Corrector Magnet Circuits during the Commissioning of the LHC acceleration, target, extraction, sextupole 2470
 
  • W. Venturini Delsolaro, V. Baggiolini, A. Ballarino, B. Bellesia, F. Bordry, A. Cantone, M. P. Casas Lino, C. CastilloTrello, N. Catalan-Lasheras, Z. Charifoulline, C. Charrondiere, G. D'Angelo, K. Dahlerup-Petersen, G. De Rijk, R. Denz, M. Gruwe, V. Kain, M. Karppinen, B. Khomenko, G. Kirby, S. L.N. Le Naour, A. Macpherson, A. Marqueta Barbero, K. H. Mess, M. Modena, R. Mompo, V. Montabonnet, D. Nisbet, V. Parma, M. Pojer, L. Ponce, A. Raimondo, S. Redaelli, V. Remondino, H. Reymond, A. Rijllart, R. I. Saban, S. Sanfilippo, K. M. Schirm, R. Schmidt, A. P. Siemko, M. Solfaroli Camillocci, H. Thiesen, Y. Thurel, A. Vergara-Fernández, A. P. Verweij, R. Wolf, M. Zerlauth
    CERN, Geneva
  • A. Castaneda, I. Romera Ramirez
    CIEMAT, Madrid
  • SF. Feher, R. H. Flora
    Fermilab, Batavia, Illinois
  The LHC is a complex machine requiring more than 7400 superconducting corrector magnets distributed along a circumference of 26.7 km. These magnets are powered in 1380 different electrical circuits with currents ranging from 60 A up to 600 A. Among the corrector circuits the 600 A corrector magnets form the most diverse and differentiated magnet circuits. About 60000 high current connections had to be made. A minor fault in a circuit or one of the superconducting connections would have severe consequences for the accelerator operation. All magnets are wound from various types of Nb-Ti superconducting strands, and many contain resistors to by-pass the current in case of the transition to the normal conducting state in case of a quench, and hence reduce the hot spot temperature. In this paper the performance of these magnet circuits is presented, focussing on the quench current and quench behaviour of the magnets. Quench detection and the performance of the electrical interconnects will be dealt with. The results as measured on the entire circuits will be compared to the test results obtained during the reception tests of the individual magnets.  
 
WEPD029 Performance of the Main Dipole Magnet Circuits of the LHC during Commissioning dipole, extraction, target, instrumentation 2473
 
  • A. P. Verweij, V. Baggiolini, A. Ballarino, B. Bellesia, F. Bordry, A. Cantone, M. P. Casas Lino, A. Castaneda, C. CastilloTrello, N. Catalan-Lasheras, Z. Charifoulline, G.-J. Coelingh, G. D'Angelo, K. Dahlerup-Petersen, G. De Rijk, R. Denz, M. Gruwe, V. Kain, B. Khomenko, G. Kirby, S. L.N. Le Naour, A. Macpherson, A. Marqueta Barbero, K. H. Mess, M. Modena, R. Mompo, V. Montabonnet, D. Nisbet, V. Parma, M. Pojer, L. Ponce, A. Raimondo, S. Redaelli, H. Reymond, D. Richter, A. Rijllart, I. Romera, R. I. Saban, S. Sanfilippo, R. Schmidt, A. P. Siemko, M. Solfaroli Camillocci, H. Thiesen, Y. Thurel, W. Venturini Delsolaro, A. Vergara-Fernández, R. Wolf, M. Zerlauth
    CERN, Geneva
  • SF. Feher, R. H. Flora
    Fermilab, Batavia, Illinois
  During hardware commissioning of the Large Hadron Collider, 8 main dipole circuits and 16 main quadrupole circuits are tested at 1.9 K and up to their nominal current. Each dipole circuit contains 154 magnets of 15 m length, and has a total stored energy of up to 1.1 GJ. Each quadrupole circuit contains 47 or 51 magnets of 5.4 m length, and has a total stored energy of up to 20 MJ. All magnets are wound from Nb-Ti superconducting Rutherford cables, and contain heaters to quickly force the transition to the normal conducting state in case of a quench, and hence reduce the hot spot temperature. In this paper the performance of these circuits is presented, focusing on the quench current and quench behaviour of the magnets. Quench detection, heater performance, operation of the cold bypass diodes, cryogenic recovery time, electrical joints, and possible magnet-to-magnet quench propagation will be dealt with. The results as measured on the entire circuits will be compared to the test results obtained during the reception tests of the individual magnets.  
 
WEPD038 Thermal and Structural Modeling of the TTF Cryomodule Cooldown and Comparison with Experimental Data simulation, radiation, controls, monitoring 2494
 
  • S. Barbanotti, P. Pierini
    INFN/LASA, Segrate (MI)
  • K. Jensch, R. Lange, W. Maschmann
    DESY, Hamburg
  The study of thermal and structural behavior during cooldown/warmup of long SRF cryostats is important for both the XFEL and ILC, which base the design on the successful TTF design. We present the finite elements analysis of the main internal components of the cryomodules during the transient cooldown and warmup, comparing the data obtained with data taken at DESY on the linac.  
 
WEPD039 Evolution of the Standard Helium Liquefier and Refrigerator Range designed by Air Liquide DTA, France synchrotron, controls, neutral-beams, simulation 2497
 
  • S. Crispel, G. Aigouy, A. Caillaud, F. Delcayre, V. Grabie
    Air Liquide, Division Techniques Avancées, Sassenage
  The standard helium liquefier and refrigerator range, called HELIAL, designed by Air Liquide DTA, has been upgraded with significant improvement of efficiency as a result of technological development.. Indeed in the demanding high tech markets, (international laboratories, aerospace applications, synchrotrons, HTS applications…), cryogenic systems must provide increasingly high performances. The new HELIAL Evolution is equipped with Air Liquide's expansion turbines, well known for their extremely high reliability and efficiency,. The results of this development endowing the HELIAL Evolution with twice liquefaction capacity, are presented in this paper.  
 
WEPD040 Outcome of the Commissioning of the Readout and Actuation Channels for the Cryogenics of the LHC controls, instrumentation, site, operational-performance 2500
 
  • G. Fernandez Penacoba, C. Balle, J. Casas-Cubillos, J. De La Gama, P. Gomes, E. Gousiou, N. Jeanmonod, A. Lopez Lorente, E. Molina Marinas, A. Suraci, N. Vauthier
    CERN, Geneva
  The installation of the Large Hadron Collider (LHC) at CERN has been completed and its commissioning is now in progress. The LHC is the largest cryogenic installation ever built. It includes 1700 superconducting magnets, a cryogenic distribution line (QRL) running parallel to the accelerator, 52 electrical distribution feedboxes (DFB) supporting the superconducting current leads that supply power to the magnets circuits, and 16 superconducting RF accelerating cavities. For its operation more than 10 000 sensors and actuators are required. The commissioning of this instrumentation includes the validation of both hardware (installed sensors, cabling, front-end electronics, communication field-buses) and software (databases extraction, programmable logic controllers programs, supervision coherence). At present point, having provided the cryogenic instrumentation for the operation in half of the LHC, more than 95% of the channels are working within specifications. This paper presents the commissioning strategy, tracking policy, and performance results after commissioning of the cryogenic instrumentation for the LHC.  
 
WEPD041 Continuous Operation of Cryogenic System for Synchrotron Light Source controls, superconducting-magnet, storage-ring, synchrotron 2503
 
  • F. Z. Hsiao, S.-H. Chang, W.-S. Chiou, H. C. Li, H. H. Tsai
    NSRRC, Hsinchu
  The availability of user time is an important index for the performance evaluation of a synchrotron light source. In NSRRC two cryogenic plants are installed for liquid helium supply to the superconducting magnets and the superconducting cavity of the electron storage ring. As a subsystem of the storage ring, the objective of continuous helium supply without interruption is important for the cryogenic plant. The target to shorten the recovery time of the storage ring, if the cryogenic plant trips, is another issue. Component failure and system maintenance are two main reasons interrupting operation of the cryogenic plant. This paper shows our strategy on the scheduled maintenance of either the cryogenic plant or the utility system to keep continuous liquid helium supply. Two tests to shorten the recovery time are presented: the first is liquid helium supply from both cryogenic plants simultaneously; the second is restarting the on-duty cryogenic plant with the other dewar providing helium to the superconducting devices.  
 
WEPD042 Development of a Simulation Module for the Cryogenic System simulation, controls, superconducting-magnet, synchrotron 2506
 
  • H. C. Li, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, H. H. Tsai
    NSRRC, Hsinchu
  In NSRRC two 450W cryogenic systems were installed on the year 2002 and 2006, respectively. After long time operation some behavior and setting parameters of the cryogenic system did not satisfy our requirement because of the deterioration of electrical sensors and valves. To ask the manufacturer to solve those problems, it took lots of time in the communication of problem description and the modification of control program. A simulation module for the cryogenic system is thus developed to trace the procedure before and after modification of the control program. This paper details the simulation module and shows the usefulness of this module on evaluation of the software modification for cryogenic system.  
 
WEPD043 Orbital Welding of QRL Line in Confined Environment vacuum, controls, alignment, collider 2509
 
  • E. P. Roussel
    Air Liquide, Sassenage
  • P. J.D. P. Mazoyer
    ORBITAL, Vonnas
  AIR LIQUIDE DTA was in charge of design, manufacturing of element and installation of QRL line of CERN. The elements of this cryogenic line have been welded by orbital welding with an open weld head. A specific welding head has been developed for the project. Radial and axial clearances lead the design of the head. To install this cryogenic line, more than 15 000 orbital welds have been realized. This paper will present the technical requirements applicable to QRL line, different welding configuration, main step to qualify welding process. We will describe the results of non destructive examination: helium leak test, X-ray inspection and visual inspection.  
 
WEPD044 Efficiency Analysis for the Cryogenic System at NSRRC simulation, superconducting-magnet, controls, synchrotron 2512
 
  • H. H. Tsai, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, H. C. Li
    NSRRC, Hsinchu
  Three superconducting magnets and one superconducting cavity for RF are cooled by two 450W liquid helium system at NSRRC. These two systems were made up of Claude cycle which is usually compared in their performance to that of the ideal Carnot cycle. This paper presents the efficiency analysis for the cryogenic system. Based on the analysis, the power transfer to the process change for the operation will be performed. In addition, it also shows the way to identify the problems when done the trouble shooting for part of erratic response of the plant. The carnot efficiency also provides an important index of the performance, especially when we done the process control.  
 
WEPD045 Hydrogen Cryosorption on Multi Walled Carbon Nanotubes vacuum, collider, background, synchrotron 2515
 
  • F. Xu, M. Barberio, P. Barone, A. Oliva, L. Papagno, V. Pirronello, R. Vasta
    INFN Gruppo di Cosenza, Arcavacata di Rende (Cosenza)
  We present a Temperature Programmed Desorption (TPD) study on H2 adsorption on multiwalled carbon nanotubes (MWNT) at very low pressure (< 10-6 Torr) and temperature (12-30 K). Our results show a hydrogen take up limit in the range of 10-8 mol per gram depending on the adsorption temperature. We compare the MWNT cryosorption capacity with that of commonly used activated carbon and discuss the possibility of employing MWNT as cryosorber in large particle accelerators.  
 
WEPP005 Measurements and Effects of the Magnetic Hysteresis on the LHC Crossing Angle and Separation Bumps simulation, beam-beam-effects, controls, dipole 2530
 
  • N. J. Sammut, H. Burkhardt, C. Giloux, W. Venturini Delsolaro, S. M. White
    CERN, Geneva
  • N. J. Sammut
    University of Malta, Faculty of Engineering, Msida
  The superconducting orbit corrector magnets (MCBC and MCBY) in the Large Hadron Collider (LHC) at CERN will be used to generate parallel separation and crossing angles at the interaction points during the different phases that will bring the LHC beams into collision. However, the field errors generated by the inherent hysteresis in the operation region of the orbit correctors may lead to unwanted orbit perturbations that could have a critical effect on luminosity. This paper presents the results obtained from dedicated cryogenic measurements on the orbit correctors from the simulated results on the impact of the hysteresis on the LHC orbit.  
 
WEPP010 Scheduling the Powering Tests extraction, superconducting-magnet, instrumentation, simulation 2545
 
  • K. Foraz, E. Barbero-Soto, B. Bellesia, M. P. Casas Lino, C. Fernandez-Robles, M. Pojer, R. I. Saban, R. Schmidt, M. Solfaroli Camillocci, A. Vergara-Fernández
    CERN, Geneva
  The Large Hadron Collider is now entering in its final phase before receiving beam, and the activities at CERN between 2007 and 2008 have shifted from installation work to the commissioning of the technical systems (“hardware commissioning”). Due to the unprecedented complexity of this machine, all the systems are or will be tested as far as possible before the cool-down starts. Systems are firstly tested individually before being globally tested together. The architecture of LHC, which is partitioned into eight cryogenically and electrically independent sectors, allows the commissioning on a sector by sector basis. When a sector reaches nominal cryogenic conditions, commissioning of the magnet powering system to nominal current for all magnets can be performed. This paper briefly describes the different activities to be performed during the powering tests of the superconducting magnet system and presents the scheduling issues raised by co-activities as well as the management of resources.  
 
WEPP030 LHC Luminosity Upgrade: Protecting Insertion Region Magnets from Collision Debris shielding, insertion, luminosity, dipole 2584
 
  • E. Y. Wildner, F. Cerutti, A. Ferrari, M. Mauri, A. Mereghetti
    CERN, Geneva
  The Large Hadron Collider built at CERN now enters a starting-up phase where with the present design luminosities up to 1034 cm-2 s-1 will be reached after the running in phase. A possible upgrading of the machine to luminosities up to 1035 cm-2 s-1 requires a completely new insertion region design, and will be implemented in essentially two phases. The energy from collision debris is deposited in the insertion regions and in particular in the superconducting magnet coils with a possible risk of quench. We describe here how to protect the interaction region magnets against this irradiation to keep the energy deposition below critical values estimated for safe operation. The constraint is to keep the absorber size as small as possible to leave most of the magnet aperture available for the beam. This can be done by choosing a suitable material and design minimizing the load on the cryogenic system. We will describe a proposal of a design for the phase I upgrade lay-out (i.e., luminosities up to 2.5 1034 cm-2 s-1).  
 
WEPP075 Effects of the Cryogenic Operational Conditions on the Mechanical Stability of the FLASH Linear Accelerator Modules quadrupole, electron, linac, controls 2692
 
  • R. Amirikas, A. Bertolini, J. Eschke, M. Lomperski
    DESY, Hamburg
  The Free electron LASer in Hamburg (FLASH) accelerating modules have been instrumented with vertical geophones on their corresponding quadrupoles and their vacuum vessels. The signals from these geophones are constantly monitored and the data are integrated into the control system of the accelerator. Therefore, vibration stability studies of a string of superconducting accelerating modules, in various cryogenic conditions, are now possible for the first time. The results of this experiment will be an important reference for both the European X-ray Free Electron Laser (XFEL) and the International Linear Collider (ILC) linear accelerators which are expected to take advantage from the separation between the feed lines of the 4.5 K shield and of the quadrupole, which will operate in a 2 K Helium-II bath.  
 
THXM02 Development of the KEK-B Superconducting Crab Cavity electron, superconductivity, positron, acceleration 2927
 
  • K. Hosoyama, K. Akai, K. Ebihara, T. Furuya, K. Hara, T. Honma, A. Kabe, Y. Kojima, S. Mitsunobu, Y. Morita, H. Nakai, K. Nakanishi, M. Ono, Y. Yamamoto
    KEK, Ibaraki
  • H. Hara, K. Okubo, K. Sennyu, T. Yanagisawa
    MHI, Kobe
  The development of the KEK-B superconducting crab cavity, including the design, production, tests and latest parameter performances should be described in this talk.  
slides icon Slides  
 
THPP051 Stochastic Cooling in the Framework of the FAIR Project at GSI pick-up, antiproton, storage-ring, vacuum 3479
 
  • F. Nolden, A. Dolinskii, B. Franzke, U. Jandewerth, T. Katayama, C. Peschke, P. Petri, M. Steck
    GSI, Darmstadt
  • D. Möhl
    CERN, Geneva
  Stochastic cooling at FAIR will be one of the instruments to get cooled beams of rare isotopes and antiprotons for high resolution experiments. Stochastic cooling systems will be installed in the CR and RESR storage rings. The Collector Ring CR is a dedicated storage ring for the first step cooling of antiproton beams (3 GeV or β=0.97) produced at the antiproton production target, and of radioactive beams (740 MeV/u or β=0.83) prepared in the Super Fragment Separator. The pick-up and kicker systems have designs which allow very efficient cooling for both particle velocities. There will be different ring optical settings for optimum cooling of antiprotons or rare isotopes. Whereas the next cooling step for rare isotopes will be electron cooling, antiprotons will be accumulated in the RESR using a similar accumulation scheme which was formerly applied at the AA at CERN. The paper presents the CR and RESR system layouts and new hardware developments.  
 
THPP132 Review of the Initial Phases of the LHC Power Converter Commissioning controls, superconducting-magnet, quadrupole, instrumentation 3670
 
  • H. Thiesen, D. Nisbet
    CERN, Geneva
  The LHC requires more than 1700 power converter systems that supply between 60A and 12kA of precisely regulated current to the superconducting magnets. For the first time at CERN these converters have been installed underground in close proximity to many other accelerator systems. In addition to the power converters themselves, many utilities such as air and water cooling, electrical power, communication networks and magnet safety systems needed to be installed and commissioned as a single system. Due to the complexity of installing and commissioning such a large infrastructure, with inevitable interaction between the different systems, a three phase test strategy was developed. The first phase comprised the manufacture, integration and reception tests of all converter sub-systems necessary for powering. The second phase covered the commissioning of all the power converters installed in their final environment with the utilities. The third phase will add the superconducting magnets and will not be covered by this paper. The planning and execution that have led to the successful completion of these initial phases are described. Results and conclusions of the testing are presented.  
 
THPP145 Machine Operation Issues Related to the Vacuum System of the ESRF vacuum, undulator, storage-ring, beam-losses 3705
 
  • R. Kersevan, M. Hahn, I. Parat, D. Schmied
    ESRF, Grenoble
  This paper deals with various operational issues related to the vacuum system of the ESRF storage ring. The impact on the vacuum pressure, beam lifetime, beam losses and other machine parameters after installation of new chambers, diagnostics, RF cavities and insertion devices, and vacuum leaks is discussed in some detail. Particular emphasis is given to the behaviour of the prototype of a 2m-long cryogenic in-vacuum undulator, a new RF cavity, and NEG-coated chambers. Lessons learned from the operation of these and other vacuum components will be extended to the proposed machine upgrade.