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MOPLT026 Equipment Manufacturing and Test Data Tracking for the LHC dipole, feedback, cryogenics 596
 
  • E. Manola-Poggioli, S.-A. Chalard, C. Delamare, T. Ladzinski, S. Mallon-Amerigo, P. Martel, S. Petit, T. Pettersson, O. Rademakers Di Rosa, B. Rousseau, A.S. Suwalska, D. Widegren
    CERN, Geneva
  The MTF system was developed at CERN to capture the design, manufacturing and test data of equipment built for LHC. Today, more than 80.000 descriptions of LHC equipment are managed using the MTF. The system handles both production data and non-conformance issues. The acquisition of the equipment data is both an organisational and a technical challenge. On the organisational side many different aspects of production and management have to be taken into account. The LHC equipment suppliers, wherever their production facilities are located, whatever their computer skills or rates of production are, need a user friendly environment to provide the data with a very limited effort on the shop floor. For expensive equipment such as the LHC dipoles a reliable and robust non-conformance methodology must be put in place, the MTF provides the required information technology support tools. The EDMS Service has developed methods, training processes and tools to cope with an extensive use of the system, a use that will grow during the next years until the LHC is installed. This paper presents the experience acquired and the solutions put in place.  
 
MOPLT032 Breakdown Resistance of Refractory Metals Compared to Copper vacuum, cathode, collider, instrumentation 614
 
  • M. Taborelli, S. Calatroni, M. Kildemo
    CERN, Geneva
  The behaviour of Mo, W and Cu with respect to electrical breakdown in ultra high vacuum has been investigated by means of a capacitor discharge method. The maximum stable electric field and the field enhancement factor, beta, have been measured between electrodes of the same material in a sphere/plane geometry for anode and cathode, respectively. The maximum stable field increases as a function of the number of breakdown events for W and Mo. In contrast, no systematic increase is observed for Cu. The highest values obtained are typically 500 MV/m for W, 350 MV/m for Mo and only 180 MV/m for Cu. This conditioning, found for the refractory metals, corresponds to a simultaneous decrease of beta and is therefore related to the field emission properties of the surface and their modification upon sparking. Accordingly, high beta values and no applicable field increase occur for Cu even after repeated breakdown. The results are in agreement with rf breakdown experiments [*] performed on prototype 30 GHz accelerating structures for the CLIC accelerator.

* W. Wuensch, C. Achard, S. Döbert, H. H. Braun, I. Syratchev, M. Taborelli, I. Wilson, "A Demonstration of High Gradient Acceleration", CERN-AB-2003-048-RF; CLIC-Note-569, Proc. PAC2003.

 
 
MOPLT138 Vibrational Stability of GLC/NLC Linear Collider: Status and R&D Plans simulation, luminosity, ground-motion, collider 863
 
  • A. Seryi, F. Asiri, F. Le Pimpec
    SLAC, Menlo Park, California
  • K. Fujii, T. Matsuda, T. Tauchi, H. Yamaoka
    KEK, Ibaraki
  Luminosity stability of the X-band linear collider will be provided by beam-based train by train steering feedbacks in the linac and at the IP, optional active stabilization of the final doublet, being developed to counteract possible excessive vibration of the detector, and optional fast intratrain feedback that would allow delivering major part of the luminosity while other systems are being commissioned. Control and reduction of the beam jitter originating from vibration of collider components is part of our strategy described in this paper.  
 
TUPKF018 Surface Morphology at the Quench Site superconductivity 1000
 
  • S. Berry, C.Z. Antoine, M. Desmons
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  It has been demonstrated recently that local magnetic field enhancement can originate from roughness (e.g. steps at grain boundaries). We are willing to investigate if the quench observed in superconducting niobium cavities can be related to such morphological defects. We recently developed two kinds of tool. 1) A replica technique that allows to reproduce the internal surface of cavities (non destructive testing). 2) A morphological analysis tool. Classical roughness measurements are not adapted to determine local curvature radius.This paper describes a new topological approach aiming at a better characterization of the surface morphology. We also present results of this technique applied to replica taken from cavities at the quench site.  
 
TUPKF068 JLAB Hurricane Recovery linac, vacuum, cryogenics, superconductivity 1102
 
  • A. Hutton, D. Arenius, F.J. Benesch, S. Chattopadhyay, E. Daly, V. Ganni, O. Garza, R. Kazimi, R. Lauze, L. Merminga, W. Merz, R. Nelson, W. Oren, M. Poelker, T. Powers, J.P. Preble, C. Reece, R.A. Rimmer, M. Spata, S. Suhring
    Jefferson Lab, Newport News, Virginia
  Hurricane Isabel, originally a Category 5 storm, arrived at Jefferson Lab on September 18 with winds of only 75 mph creating little direct damage to the infrastructure. However, electric power was lost for four days allowing the superconducting cryomodules to warm up and causing a total loss of the liquid helium. The subsequent recovery of the cryomodules and the impact of the considerable amount of opportunistic preventive maintenance provides important lessons for all accelerators complexes, not only those with superconducting elements. The details of how the recovery process was structured and the resulting improvement in accelerator availability will be discussed in detail.  
 
TUPLT022 Beam Dynamics Simulations at the S-DALINAC for the Optimal Position of Beam Energy Monitors simulation, extraction, optics, electron 1186
 
  • B. Steiner, W.F.O. Müller, T. Weiland
    TEMF, Darmstadt
  • A. Richter
    TU Darmstadt, Darmstadt
  The S-DALINAC is a 130 MeV superconducting recirculating electron accelerator serving several nuclear and radiation physics experiments as well as driving an infrared free-electron laser. For the experiments an energy stability of 1·10-4 should be reached. Therefore noninvasive beam position monitors will be used to measure the beam energy. For the measurement the different flight time of the electrons to the ideal particle are compared, that means in the simulations the longitudinal dispersion of the beam transport system is used for the energy detection. The results of the simulations show that it is possible to detect an energy difference of 1·10-4 with this method. The results are also proven by measurements.  
 
TUPLT085 J-PARC Construction and its Linac Commissioning linac, proton, synchrotron, quadrupole 1351
 
  • Y. Yamazaki
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  The J-PARC(Japan Proton Accelerator Research Complex) accelerator is under construction in JAERI Tokai site. The beam commissioning will be started there by the end of 2006. Prior to this, the front end of the linac was beam-commissioned in 2003 at KEK. The negative hydrogen beam with a peak current of 30 mA was accelerated up to 20 MeV by the first tank of three DTL's following the 3-MeV RFQ linac. The 324-MHz DTL contains the electro quadrupole magnets with water-cooling channels specially fabricated by means of electroforming and wire-cutting technologies. The construction status of the J-PARC accelerator is also presented.  
 
TUPLT091 Fabrication Status of the PEFP 20 MeV DTL vacuum, quadrupole, proton, pick-up 1369
 
  • M.-Y. Park, Y.-S. Cho, J.-H. Jang, Y.H. Kim, H.-J. Kwon
    KAERI, Daejon
  The PEFP (Proton Engineering Frontier Project) 20 MeV DTL have been constructed in KAERI site. The fabrication of the first tank is finished and the DT installation is in the process. We choose the pool-type electromagnets as the focusing magnet and 50 DTs will be installed on first tank. We tested the winding schemes of copper coils on the iron core and measured the magnetic field saturation.In this paper, the results of the tank fabrication and quadrupole magnet test are presented.  
 
TUPLT167 Installation of the Spallation Neutron Source (SNS) Warm Linac vacuum, alignment, linac, quadrupole 1521
 
  • P.E. Gibson, C. Deibele, J.J. Error, G.A.J. Johnson, P. Ladd
    ORNL/SNS, Oak Ridge, Tennessee
  • N.K. Bultman
    LANL, Los Alamos, New Mexico
  The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built at Oak Ridge National Laboratory. The SNS project design and construction is a partnership involving six DOE national laboratories including Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Oak Ridge, and Los Alamos. When completed in 2006, the SNS will provide the most intense, pulsed neutron beams in the world for scientific research and industrial development. At the present time we are installing and commissioning the warm linac system, designed by Los Alamos, and have to date had good success. The warm linac is comprised of six Drift Tube Linac (DTL) tanks and four Coupled Cavity Linac (CCL) modules. These accept an incoming negative hydrogen ion beam from the Front End injector at 2.5 MeV, and accelerate to a final energy of 185 MeV. At this time we have installed and commissioned DTL tanks 1-3 and installed CCL module 1 . Experience and information gained during installation will be presented. The performance in terms of alignment, vacuum and field tuning will be described.  
 
WEPKF019 Magnetic Measurement Systems for the LHC Dipole Assembly Firms dipole, power-supply, controls, alignment 1636
 
  • H. Reymond, J. Billan, J. Garcia Perez, D. Giloteaux, A. Raimondo, V. Remondino, A. Rijllart
    CERN, Geneva
  The LHC lattice superconducting dipole magnets are actually under construction in three European industries. Due to the extremely high magnet performance required for the LHC, these magnets have to be built with high accuracy during all the steps of their assembling. In order to detect defects in the earliest production phases and to ensure the quality of the magnetic field as specified by the CERN contracts, dedicated measurement benches have been built and installed in each industry to validate the magnetic field quality at two important production stages. This paper describes the initial requirements and the implementation of the magnetic measurement systems. Details on the technical solutions, the present status and measurement results are presented.  
 
WEPKF024 The Geometry of the LHC Main Dipole dipole, sextupole 1648
 
  • E.Y. Wildner, J. Beauquis, G. Gubello, M. La China, W. Scandale
    CERN, Geneva
  The 15 m long main dipole of the Large Hadron Collider has a curvature following the beam trajectory with the aim to minimize the necessary coil aperture. To avoid feed-down effects and mechanical aperture restrictions strong constraints have to be imposed on the construction of the magnet in terms of tolerances and stability of the cold mass during transport, cryostating, cold tests and installation in the LHC tunnel. In this paper we show the behaviour of the shape of the magnet using available measurements taken at different stages of construction and assembly. In particular we discuss the evolution of the sagitta and the positioning of the corrector magnets that are used to compensate the multipole field errors. We propose alignment procedures to be used in case magnets are out of tolerance after transport and cold tests. The twist of the magnet and its relation to the field angle will also be discussed.  
 
WEPKF048 Characteristics of Ground Motion at KEK and SPring-8 ground-motion, power-supply, linear-collider, collider 1711
 
  • Y. Nakayama, T. Ito
    JPOWER, Kanagawa-ken
  • S. Matsui, C. Zhang
    JASRI/SPring-8, Hyogo
  • R. Sugahara, S. Takeda, H. Yamaoka, M. Yoshioka
    KEK, Ibaraki
  • S. Yamashita
    University of Tokyo, Tokyo
  Authors Y. Nakayama, T. Ito, (JPOWER); R. Sugahara, S. Takeda, H.Yamaoka, M.Yoshioka (KEK); S.Matsui, C.Zhang (SPring-8); S. Yamashita (ICEPP): Abstract Stability of ground is preferable for accelerator beam operation. We have measured ground motion of ground at the KEKB and SPring-8 site, where the ground has quite different characteristics each other. In this paper, some of analysis results are shown, and the characteristics of the ground motion at the KEKB site and those at the Spring-8 site are compared.  
 
WEPLT010 Design and Fabrication of Superfluid Helium Heat Exchanger Tubes for the LHC Superconducting Magnets vacuum, electron, quadrupole, dipole 1837
 
  • F.F. Bertinelli, G. Favre, L.M.A. Ferreira, S.J. Mathot, L. Rossi, F. Savary
    CERN, Geneva
  • E. Boter
    CELLS, Bellaterra (Cerdanyola del Vallès)
  The dipole and quadrupole cold masses of the LHC machine require about 1700 heat exchanger tubes (HET). In operation the HET carries a two-phase flow of superfluid helium at sub-atmospheric pressure. The HET consists of an oxygen-free, seamless copper tube equipped with stainless steel ends. After an evaluation of different design alternatives, a design based on the technologies of vacuum brazing and electron beam welding has been adopted. Presence of these multiple technologies at CERN and synergies with the cleaning, handling and transport of other 15-metre components for LHC, motivated CERN to undertake this series fabrication on site. The raw copper tubes are procured in Industry, presenting challenging issues of geometric precision. Organisation of the HET fabrication includes cryomeasurements to validate cleaning procedures, characterization of welding procedures, buckling design by FEA and experimental verification, quality control during series production. The series fabrication of these long, multi-technological components is continuing successfully, respecting the project?s tight budgetary and planning constraints.  
 
WEPLT011 Transport and Handling of LHC Components: a Permanent Challenge shielding, simulation, collider, cryogenics 1840
 
  • C. Bertone, I. Ruehl
    CERN, Geneva
  The LHC project, collider and experiments, is an assembly of thousands of elements, large or small, heavy or light, fragile. Every one of those has own transport requirements that constituting for us a real challenge to handle. The manoeuvres could be simple, but the complex environment and narrow underground spaces may lead to difficulties in integration, routing and execution. Examples of transport and handling of typical LHC elements will be detailed: the 17m long, 35t heavy but fragile cryomagnets from the surface to the final destination in the tunnel, the delicate cryogenic cold-boxes down to pits and detector components. This challenge did not only require a lot of imagination but also the close cooperation between all involved parties, in particular with colleagues from safety, cryogenics, civil engineering, integration and logistics.  
 
WEPLT020 Installation of A Particle Accelerator: from Theory to Practice. The LHC Example collider, feedback, vacuum, survey 1867
 
  • C. Hauviller, S. Weisz
    CERN, Geneva
  Installing and commissioning the thousands of equipments constituting a Particle Accelerator is a lengthy and complex process. A large number of multidisciplinary teams are involved over a long period lasting usually many years. Diverse boundary constrains must be taken into account: space, a long and narrow tunnel with few accesses, time, with milestones set many years in advance, and obviously budget. A strict organisation associated with the management tools and the right people is the only way to arrive to a success. The keywords are: Knowledge: A unique and up-to-date database of all the elements and their location, Integration: Study the physical position of the elements, suppress the interferences and define the installation methodology, Prevision: Schedule all the activities and update on-line, In-situ management and supervision: Teams dedicated to follow-up, corrective actions and orphan jobs, Safety. After presenting the planned overall organization, the paper will present practical achievements with the example of the LHC machine installation.  
 
WEPLT031 The LHC Access Control System injection, man-machine-interface 1900
 
  • P. Ninin, L. Scibile
    CERN, Geneva
  The LHC complex is divided into a number of zones with different levels of access controls. Inside the interlocked areas, the personnel protection is ensured by the LHC Access System. This system is made of two parts: the LHC Access Safety System and the LHC Access Control System. During machine operation, the LHC Access Safety System ensures the collective protection of the personnel against the hazards arising from the operation of the accelerator. By interlocking the LHC key safety elements, it will permit access to authorised personnel in the underground premises during the accelerator shutdowns and will deny access during accelerator operation. On the other hand, the LHC Access Control System, regulates the access to the accelerator and the numerous support systems. It allows a remote, local or automatic operation of the access control equipment that verifies the users? authorization, identifies them, locks and unlocks access control equipment and restricts the number of users working simultaneously in the interlocked areas. This paper introduces the main functions, architecture, technologies and methodology used to realise the LHC Access system.  
 
WEPLT040 Layout Drawings of the LHC Collider vacuum, collider, cryogenics, survey 1921
 
  • A. Vergara-Fernández, S. Chemli, B. Maire, Y. Muttoni
    CERN, Geneva
  • A. Kournossenko, R. Zalyalov
    IHEP Protvino, Protvino, Moscow Region
  The team in charge of the LHC integration largely uses 3D scenes combining functional positions of equipments and the 3D CAD model issued from the Cern Drawing Directory (CDD) repository. This is made possible through the Digital Mock-Up tool developed at CERN. Giving dimensions in 3D context is a challenge with the current 3D CAD tools used at CERN. Requirements from users groups have made clear a need for automatic production of 2D layout drawings. This paper presents the retained solution to create on-request dimensioned drawings, to publish them, while maintaining coherence and consistency with the 3D integration scenes. Reliability of the information, on-line availability of the latest layout changes on dimensions and positions of equipments, and the maintenance of the facility will also be described.  
 
WEPLT042 Scheduling the Installation of the Large Hadron Collider injection, civil-engineering, feedback, extraction 1927
 
  • S. Weisz, K. Foraz, H. Gaillard, L. Lari
    CERN, Geneva
  The size and complexity of the LHC project at CERN calls for a strong co-ordination of all installation activities. The detailed installation planning has to take into account many constraints such as the component production rates, the installation contracts or the transport and handling requirements in a narrow tunnel with limited access points. The planning also needs to be flexible enough to cope with aleas that are unavoidable in such a large project that spans over many years. This paper describes the methodology followed by the team responsible for the planning and logistics in order to stay reactive to the actual progress of the installation and to keep optimizing the usage of resources.  
 
WEPLT065 Hybrid Dry Coolers in Cooling Systems of High Energy Physics Accelerators simulation, synchrotron, linac 1996
 
  • J.-P. Jensen, B. Conrad, U. Schuetz, F.-R. Ullrich, A. Wanning
    DESY, Hamburg
  Wet water cooling towers in high energy physics accelerators are state of the art. The advantages are robustness, effectiveness and cost-effectiveness. The return water temperature is lower than the air temperature due to cooling via evaporation. The disadvantages are the high water consumption, which becomes more costly in the future, and the soiling of the heat exchangers. If the water source is taken from wells then the drawdown of the ground water level has to be taken into account. DESY plans to use hybrid dry coolers for the two future projects: The XFEL linac and the PETRA 3 synchrotron light source. A hybrid dry cooler is a combination of a dry air cooler during cold and moderate seasons and additional wet cooling during the hot summer season. The cooling surface is wetted by adding water to increase the cooling capability by a factor of 250 %. The hybrid dry cooler saves a lot of water. The water consumption can be reduced by 70% compared to a wet cooling system. This contribution presents the auxiliary water consumption, the requirement of this water and an estimate of the temperature control behaviour of the hybrid dry cooling system.  
 
WEPLT113 Development of New Hydrostatic Levelling Equipment for Large Next Generation Accelerator ground-motion, alignment, klystron, target 2113
 
  • S. Takeda
    KEK, Ibaraki
  The Hydrostatic Levelling Systems (HLS) are installed and commissioned in many laboratories. We have developed a new type hydrostatic levelling equipment for the large future accelerator. The designing points are as followings: (1) use of half filled water level sensor instead of the usual full filled level sensor, (2) the capacitive sensor is supported by an invar rod and (3) use of digitized signal transfer system. These three points are very important factor to apply the leveling system to large next generation accelerator in order to obtain good temperature stability and being free from the environmental electronic noises. We have obtained a typical resolution of the equipment as 0.3 micron-meter, though usual HLS shows the value ten times as much. We are going to show a detailed report about the system including data obtained.  
 
THZCH03 JACoW, a Collaboration Serving the Accelerator Community feedback, linac, cyclotron 249
 
  • J. Poole, C. Petit-Jean-Genaz
    CERN, Geneva
  The Joint Accelerator Conferences Website started from an idea to publish the conference proceedings on the WWW and has grown to an international collaboration which does much more than just publish the proceedings and is currently supported by seven conference series. Through attendance at Steering Committee meetings and Team Meetings and through active participation in the work of the editorial teams of sister conferences, people with the responsibility for the production of the electronic versions of conference proceedings come together to learn from the experience of colleagues, and to develop common approaches to problems. The activities of the collaboration cover all aspects of electronic publication and have recently extended into conference scientific programme management. This paper reviews the history of the collaboration, describes some of the highlights in the activities during the life of the collaboration and presents the current status and future plans.  
Video of talk
Transparencies
 
THPKF004 The Australian Synchrotron Project - Update synchrotron, storage-ring, injection, insertion 2260
 
  • A. Jackson
    ASP, Melbourne
  The Australian Synchrotron - a 3rd generation synchrotron light facility based on a 3-GeV electron storage ring - is under construction at a site adjacent to Monash University in the Metropolitan District of Melbourne. Site preparation started in September 2003 and project completion is scheduled for March 2007. In this paper we present an overview of the facility and discuss progress to date in meeting this very agressive schedule.  
 
THPKF011 Vibration Measurements at the Swiss Light Source (SLS) quadrupole, resonance, ground-motion, lattice 2278
 
  • S. Redaelli, R.W. Assmann, W. Coosemans
    CERN, Geneva
  • M. Böge, M. Dehler, L. Rivkin
    PSI, Villigen
  Vibration measurements have been carried out at the Swiss Light Source (SLS) site as part of a collaboration between the Paul Scherrer Institute (PSI) and the European Organization for Nuclear Research (CERN). The vibration level of the SLS floor and of some lattice elements of the SLS ring have been monitored under various experimental conditions. In particular, vibration spectra of lattice quadrupoles have been measured with a circulating beam and compared with the spectra of transverse beam positions, as measured with beam position monitors. This paper summarizes the results.  
 
THPLT156 Simulations of IP Feedback and Stabilization in the NLC feedback, luminosity, simulation, ground-motion 2825
 
  • L. Hendrickson, J.C. Frisch, T.M. Himel, T.O. Raubenheimer, A. Seryi, M. Woodley
    SLAC, Menlo Park, California
  • G.R. White
    Queen Mary University of London, London
  Keeping nanometer-sized beams in collision is an essential component in achieving design luminosity in a linear collider. The NLC stabilization strategy is conservative by including enough redundancy so that if some piece doesn't work to specification or the incoming beam motion is worse than expected, the beams will still be kept in collision. We show simulation results with both realistic and pessimistic assumptions about the response of the ground motion, inertial stabilization, interbunch and intertrain feedback systems. By providing backup systems, and by assuming that some systems may perform more poorly than expected, we can achieve a high level of confidence in our ability to successfully stabilize the beams.