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Scientific and Technical Report 2001 Volume VI Large Research Facilities

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Scientific and Technical Report 2001 Volume VI Large Research Facilities PAUL SCHERRER INSTITUT ISSN 1423-7350 March 2002 Scientific and Technical Report 2001 Volume VI Large Research Facilities ed. by: Renate Bercher, Carmen Büchli, Lotty Zumkeller CH-5232 Villigen PSI Switzerland Phone: 056/310 21 11 Telefax: 056/31021 99 http://www.psi.ch I TABLE OF CONTENTS Foreword l Accelerator Physics and Development Operation of the PSI-accelerator facility in 2001 5 Progress in the production of the new ring cyclotron cavity 7 Coupled field analysis of the new ring cyclotron cavity 9 Experimental upgrade of the injector II150 MHz RF system 11 Replacement of magnet power supplies, control and field-bus for the PSI cyclotron accelerators 13 Investigations on discharges of high voltage devices based on a transient recorder program 15 Test of a radio-frequency-driven mulitcusp proton source 16 Emittance measurements at the PSI ECR heavy ion source 17 Profile measurement of scanning proton beam for LiSoR using carbon fibre harps 18 A fast dégrader to set the energies for the application of the depth dose in proton therapy 20 MAD9P a parallel 3D particle tracker with space charge 22 Behaviour of the different poisson solvers in the light of beam dynamics simulations 24 Computational electrodynamics on the LINUX-cluster 26 Particle ray-tracing program TRACK applied to accelerators 27 Experimental Facilities Rebuilt beam line section between the targets M and E 31 Disposal preparation for meson production targets 33 A novel method to improve the safety of the planned MEGAPIE target at SINQ 34 Beamline adaptation for the MEGAPIE-target 36 Programme "TUR" and two uniform number generators 37 Conceptual design of the spallation target for the ultra cold neutron source UCN 38 Shielding and activation calculations for an ultracold neutron facility at PSI 41 A rotating filter for the materials science beamline of the SLS 43 Spallation Neutron Source The Spallation Neutron Source Division ASQ: An overview 47 From the Kantonsschule to the MEGAPIE-project 50 Status of the MEGAPIE-project and the international collaboration 51 Configuration optimisation of concave target safety enclosures 53 Hypothetical accident analysis on falling container of the MEGAPIE-target 55 Heat transfer in the case of leaking target material 57 Influence of freezing of Lead-Bismuth Eutectic on the strain distribution in a model container 59 Volume change of LBE after solidification 61 Calculated power deposition in the liquid lead bismuth and target lower enclosures of the MEGAPIE target 63 KILOPIE - Design of a thermal hydraulic experiment for the MEGAPIE target window 65 Tensile testing of MANET II in flowing Pb-Bi at elevated temperature in LiSoR loop 67 SINQ target irradiation programs, STIP-II and STIP-III 69 Temperature dependence of the microstructure of high energy proton irradiated F82H martensitic steel 71 Tensile properties of T91 irrdiated at SINQ-target MARK-II to 10 dpa 73 Liquid metal loop LiSoR 74 Stress wave experiments with the ASTE mercury spallation target 75 Status of the strain-field diffractometer POLDI 77 Experiments on the magnetic flux line lattice in the high temperature superconductor YBCO in high magnetic fields 78 Applied energy-selective neutron radiography and tomography at the PGA station 79 Neutron radiography with fast neutrons at 14-MeV accelerator source 81 Investigation of the hydrogen accumulation in the cladding material of nuclear fuel by neutron radiography 83 Dynamic behaviour of the water distribution in wet aramid-based ballistic body armour panels investigated by neutron radiography 85 II Setup of CCD based detection system at the NCR station 86 3D investigations of pore size distribution in sandstone 87 Selective radiography of 10B distribution in organs using cold and thermal neutron beams 88 On-line gamma-spectrometric measurements of short-lived radioisotopes inmigration experiments at the Grimsel Test site 89 Characterisation of thermally sprayed deposits, treated by hot isostatic pressing (HIP) 90 Characterization of void morphologies in thermally sprayed metallic deposits using scattering techniques 91 Intergranular fracture in nanocrystalline metals 93 Computer simulation of displacement cascades in nanocrystalline metals 94 Structural and mechanical properties of nanocrystalline FCC metals 95 Low-frequency vibrational properties of nanocrystalline materials 97 Atomistic simulations of nanoindentation in interface dominated materials 98 Microstructural analysis of electrodeposited and severe plastically deformed Ni and their mechanical behaviour.... 99 Structure of lipid bilayers of dimeric ionpaired amphiphiles 101 Role of counterion distribution on the structure of micelles in aqueous salt solution 102 Technical Support and Co-ordination Versatility of the ATK division 105 The PROSCAN project: a progress report 109 List of publications 111 Contributions to conferences and workshops 115 Lectures and courses 122 Dissertations 123 Members of scientific committees 123 Awards 124 Reports / books 124 Chapter in book 124 1 Wildenstein, a strong• of operation, during which 10Ah of beam have been hold dating back to the accumulated, we will prophylactically replace the spallation 13th century, was the target with a new one of the same type. At the same time, meeting place for a one- we will be able to examine the materials, which have been day workshop in June exposed to this intense radiation dose. 2001 on measures to improve the availability Besides our work on maintenance and improvement of of our proton accelera• existing equipment, we are also involved in new and novel tors and their auxiliary enterprises. Just a few days before Christmas, our strain systems. Although we field diffractometer POLDI saw its first neutrons; LISOR, a do not expect our unique apparatus to test corrosion effects and liquid metal facilities to be still embrittlement under radiation at elevated temperatures, was operational 700 years from now, we felt that similarities in completed and installed on an Injector 1 proton beam line. the history, albeit on different time scales, of the stronghold We have also been heavily involved in the PROSCAN and our accelerators might be a nice symbol of our project, which comprises a novel superconducting cyclo• endeavor. Both places have changed their purpose over the tron, beam Unes to the existing and also to a new gantry for years: Wildenstein from a stronghold of local knights to a an efficient and improved proton therapy program. Thanks gathering place of Swiss troops against the armies of the to the comprehensive expertise of our staff, a first-rate French king and later to a summer resort and meeting place; accelerator could be designed and ordered from a European our research facility from an instrument to study industrial company in collaboration with fellow institutes. fundamental forces of nature to a multipurpose facility, We could also find an excellent solution for the beam lines which is also used for research in materials sciences and for and shielding in a difficult topology. Progress has been medical applications. The secret of longevity of castle and made in the MEGAPIE project, which will eventually allow accelerator is adaptation to new needs and intensive and us to substantially increase the SINQ neutron flux by careful maintenance. utilizing liquid lead bismuth eutectic as target material. Although the retirement of the initiator and technical While the main effort in the past ten years was directed project director of this large international collaboration, Dr. Guenter Bauer, appeared to be a serious setback, we could towards increasing the beam current from 100 to 2000 uA fortunately acquire two competent and enthusiastic and installation of additional user facilities like SINQ to collaborators as technical manager and controller. Besides satisfy new needs, we are now concentrating on stable our intensive support of SLS, including experimental operation at these high beam intensities. Unfortunately, equipment, there are a number of projects from other "stable operation" is not clearly defined. A few years ago, departments such as the ultracold neutron source UCN, the the accelerator physicists considered 80% beam on time low energy muon beam LEM, assembly of a fuel cell excellent but the users complained about poor performance. powered car and handling and disposal of radioactive Today we achieve a yearly mean beam on time of almost waste, where we deliver important technical and scientific 90% at 1.7 mA and we have achieved 95% to 98% of the contributions. scheduled beam time for periods of weeks. These numbers seem to be satisfactory for the users. Despite this achievement, we try hard to further reduce the number of Even though our main task remains the operation and serious and long breakdowns, which are the main cause of improvement of the large accelerator facilities, we also the reduced yearly mean availability. Furthermore, work on or collaborate in research projects. Only a fraction breakdowns that necessitate long repair times are extremely of our workforce can be devoted to these activities, but this detrimental for many experiments, which have only been fraction provides an essential motivation for the scientific allocated a few days of beam time. As a result of our personnel and it also has a big impact on our understanding discussions, we launched a number of activities, which and fulfillment of the requirements of research at our include design and construction of improved power facilities. As a direct consequence of theoretical studies
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