Paper | Title | Other Keywords | Page | ||||||
---|---|---|---|---|---|---|---|---|---|
MOXACH01 | Worldwide Perspectives in Accelerators and the Rôle of CERN | collider, proton, linear-collider, luminosity | 1 | ||||||
|
After an analysis of the most probable medium and long-term evolution of Particle Accelerators and their worldwide perspectives, the presentation focuses on the specific role of CERN. It emphasizes CERNs mandate as defined by its convention, which is not only to build and operate the laboratory as a centre of excellence but to organize and steer particle physics in Europe. It should be the place where a coherent strategy for the whole field of European Particle Physics is discussed and elaborated in the best interest of the whole community. CERN should act as the driving force in the centre of a network of multilateral collaborating institutes where each laboratory brings its own contribution towards a common goal in a coordinated way following its specific skills and resources. It should favour mutual exchanges and collaborations to enable developments covering the whole range of CERN's activities from pure physics to accelerator and detector R&D. This is a necessary condition not only to make the LHC a success as the highest priority during the next few years, but also for Europe to continue its leading role in the quest to push further the high energy frontier in the future. That will require even more challenging and more complex facilities which will only be possible if built as unique and complementary in world-wide collaborations.
|
|
|
Video of talk
|
|
Transparencies
|
|
||
MOPLT052 | Emittance Growth and Beam Lifetime Limitations due to Beam-beam Effects in e+e- Storage Ring Colliders | emittance, beam-beam-effects, luminosity, electron | 668 | ||||||
|
In this paper we give analytical expressions for the maximum beam-beam parameter and related beam-beam limited beam lifetime in e+e- storage ring colliders. After analysing the performances of existing or existed machines, we make some discussions on the parameter choice for the Super-B factory design.
|
|
|
||||||
MOPLT053 | On Parasitic Crossings and their Limitations to e+e- Storage Ring Colliders | luminosity, beam-beam-effects, storage-ring, collider | 671 | ||||||
|
We treat the problem of parasitic crossing in e+e- storage ring colliders analytically. Analytical formulae for the beam lifetime limited by the combined effects of beam-beam interactions at interaction point and at parasitic crossings are derived, and applied to the by-2 colliding mode of PEP-II low energy ring.
|
|
|
||||||
MOPLT069 | Investigation of Injection for the Low-emittance Lattice with New-6.25 ohm Kicker Magnet System at the Photon Factory | kicker, injection, lattice, photon | 710 | ||||||
|
We installed 6.25ohm traveling-wave kicker magnet in the Photon Factory to obtain a wide acceptance for the injected beam into the low-emittance lattice of the Photon Factory. We investigate the injection for the low-emittance lattice with this 6.25ohm kicker magnet system. Hence we have optical beam diagnostic systems which source point is inside of injection bump, we use this system for the investigation of injection. The pulse shape of the injection bump was measured by the optical beam profile monitor with high-speed gated camera by using a stored beam. The result of pulse shape of injection bump was agreed with the predicted one by using result of magnetic field measurement, and pulse duration was shorter than twice of revolution time. The instantaneous beam profile of injected beam was observed in turn by turn by using the same beam profile monitor system. We measure the turn by turn position of the injected beam from this observation and compare with a simulation. We also observe a smear out of beam oscillation by nonlinear effect from this instantaneous beam profile measurement.
|
|
|
||||||
MOPLT106 | MICE: the Muon Ionisation Cooling Experiment | emittance, background, scattering, instrumentation | 782 | ||||||
|
The provision of intense stored muon beams would allow the properties of neutrinos to be measured precisely and provide a route to multi-TeV lepton-anti-lepton collisions. The short muon-lifetime makes it impossible to employ traditional cooling techniques while maintaining the muon-beam intensity. Ionisation cooling, a process in which the muon beam is passed through a series of liquid hydrogen absorbers followed by accelerating RF-cavities, is the proposed cooling technique. The international Muon Ionisation Cooling Experiment (MICE) collaboration proposes to perform an engineering demonstration of ionisation cooling. The MICE cooling channel, the instrumentation and the implementation at the Rutherford Appleton Laboratory is described together with the predicted performance of the channel and the measurements that will be made.
|
|
|
||||||
MOPLT112 | Optimizing Non-Scaling FFAG Lattices for Rapid Acceleration | acceleration, lattice, quadrupole, electron | 800 | ||||||
|
A linear approach to fixed field acceleration was first proposed [*,**] and successfully developed to support the rapid and large-emittance acceleration of muons for a Neutrino Factory or Muon Collider. Lattices have evolved from a simple F0D0-cell base as first proposed to a slightly more complex layout that has been referred to as a triplet configuration. In this work a methodology is developed for optimizing nonscaling lattices which demonstrates that the appropriate description is minimum momentum compaction, alpha=(dL/L)/(dp/p). Further, the triplet configuration is not used conventionally as a focusing telescope, but rather its optics is shown to resemble that of a F0D0-cell. This methodology is then used to propose and compare lattices for muon acceleration. Specifically a 2.5-5, 5-10, and 10-20 GeV/c lattice is proposed for muon acceleration and also one for a small, 10-20 MeV/c electron prototype machine.
|
* C. Johnstone, "FFAG Non-scaling Lattice Design", talk, Proc 4th Int Conf on the Physics Potential and Development of the m+ m- Colliders, San Francisco, CA Dec.10-12, 1997, pgs 696-698** F. Mills, "Linear Orbit Recirculators", ibid, pgs 693-696 |
|
||||||
MOPLT118 | Muon Test Area at Fermilab | linac, beam-cooling, booster, instrumentation | 812 | ||||||
|
A construction of a new experimental area designed to develop, test and verify muon ionization cooling using the 400- MeV Fermilab Linac proton beam was finished in fall of 2003. This area will be used initially for cryogenic tests of liquid-hydrogen absorbers for the MUCOOL R&D program and, later, for high-power beam tests of these absorbers and other prototype muon-cooling apparatus. The experimental scenarios being developed for muon facilities involve collection, capture, and cooling of large-emittance, high-intensity muon beams~1013 muons at a repetition rate of 15Hz, so that conclusive tests of the apparatus require full Linac beam, or 1.6 x 1013 p at 15 Hz. The area has 12MW 805MHz, 5MW 201MHz RF, 4K Helium, 500W refrigeration and 400MeV H-/proton beam.
|
|
|
||||||
MOPLT119 | Fabrication of X-band Accelerating Structures at FERMILAB | vacuum, RF-structure, alignment, simulation | 815 | ||||||
|
The RF Technology Development group at Fermilab is working together with the NLC and GLC groups at SLAC and KEK on developing technology for room temperature X-band accelerating structures for a future linear collider. We built seven 60cm long, high phase advance, detuned structures (HDS or FXB series). These structures have 150 degrees phase advance per cell, and are intended for high gradient tests. The structures were brazed in a vacuum furnace with a partial pressure of argon, rather than in a hydrogen atmosphere. We have also begun to build 60cm long, damped and detuned structures (HDDS or FXC / FXD series). So far, we have built 3 FXC structures. Our goal is to build 4 FXC and 2 FXD structures for the 8-pack test at SLAC by the end of March 2004, as part of the GLC/NLC effort to demonstrate the readiness of room temperature RF technology for a linear collider. This poster describes the RF structure factory infrastructure (clean rooms, vacuum furnaces, vacuum equipment, RF equipment etc.), and the fabrication techniques utilized (the machining of copper cells / couplers, quality control, etching, vacuum brazing, cleanliness requirements etc.) for the production of FXB and FXC structures.
|
|
|
||||||
MOPLT144 | Design for a 1036 Super-B-factory at PEP-II | luminosity, interaction-region, collider, injection | 878 | ||||||
|
Design studies are underway to arrive at a complete parameter set for a very high luminosity e+e- Super B-Factory (SBF) in the luminosity range approaching 1036/cm2/s. The design is based on a collider in the PEP-II tunnel but with an upgraded RF system (higher frequency), magnets, vacuum system, and interaction region. The accelerator physics issues associated with this design are reviewed as well as the site and power constraints. Near term future studies will be discussed.
|
|
|
||||||
TUPKF005 | Inductive Output Tube Based 300 kW RF Amplifiers for the Diamond Light Source | power-supply, klystron, synchrotron, target | 962 | ||||||
|
All currently operating synchrotron light sources use klystron amplifiers to generate the RF power for the accelerator cavities. In TV broadcasting systems on the other hand, Inductive Output Tubes (IOT)are replacing the classical klystron based systems in all new high power UHF transmitters. The Diamond Light Source will be the first synchrotron to be operated using IOTs. For each accelerating cavity a total of four IOTs will be combined with a waveguide combiner to achieve the RF power requirement of 300 kW at 500 MHz. All IOTs will be supplied from a common crowbarless high voltage power supply. Three such systems will be installed starting in October 2004. This paper gives an overview of the design of the amplifiers, including the first test results from the factory commissioning.
|
|
|
||||||
TUPKF038 | Reduced Length Designs of 500 MHz Damped Cavity Using SiC Microwave Absorber | storage-ring, undulator, impedance, synchrotron | 1048 | ||||||
|
We present a new 500 MHz HOM (Higher-Order Modes) damped cavity for high brilliance synchrotron radiation sources. The design is based on the damped cavity, which is operated at the Photon Factory storage ring in KEK. The PF cavity has a large hole beam duct (140 mm in diameter), a part of which is made of a silicon carbide (SiC) microwave absorber. The new cavity, proposed in this paper, has parallel-plate radial transmission lines on the beam duct instead of the SiC beam duct. The outer end of the radial line is terminated by SiC absorbers. The HOMs, extracted from the center part of the cavity through the beam duct, propagate in the radial line and are dissipated in the absorber. The accelerating mode is not affected by the radial line damper since the frequency is sufficiently below the cutoff of the 140-mm beam duct. In this paper, optimized design of the radial line damper and damping properties for HOMs are described in detail.
|
|
|
||||||
WEPKF042 | Installation and Operation of New Klystron Power Supply with Fast Solid-State Switch for Klystron Protection at the Photon Factory Storage Ring | power-supply, klystron, storage-ring, photon | 1699 | ||||||
|
In the 2.5-GeV Photon Factory storage ring at KEK, there are four klystron power supplies which typically operate at an output voltage of -40 kV with 8 A. We replaced one of these power supplies during 2003 and the new power supply is in operation. This power supply is equipped with a solid-state high-voltage (HV) switch for klystron protection. This HV switch is made up of eighty insulated gate bipolar transistors (IGBT), and it can turn the high-voltage off within a few tens of microseconds in cases of any discharges in the klystrons. We report the performance of this new power supply.
|
|
|
||||||
WEPKF043 | Measurement of the Vertical Quadrupolar Tune Shift in the Photon Factory Storage Ring | storage-ring, betatron, single-bunch, photon | 1702 | ||||||
|
We measured the frequencies of vertical quadrupole oscillations in the 2.5-GeV Photon Factory storage ring at KEK. The measured vertical quadrupole tunes showed remarkable dependence of about -7.5E-5/mA on the bunch current. This contrasts with our previous result of about +4.8E-5/mA (presented in PAC2003) for the horizontal quadrupole tune shift. These results will suggest that the transverse wake forces in a quadrupolar mode contribute significantly to the transverse motions of particles in the Photon Factory storage ring.
|
|
|
||||||
WEPLT022 | Transport and Installation of Cryo-magnets in CERN's Large Hadron Collider Tunnel | acceleration, dipole, collider, hadron | 1873 | ||||||
|
The arcs of the Large Hadron Collider (LHC) will contain around 1700 main superconducting dipoles and quadrupoles. The long and heavy magnets are supported on fragile composite support posts inside a cryostat to reduce the heat in-leak to the magnets' super fluid helium bath. The presence of fragile components and the need to avoid geometry changes make the cryo-magnets very difficult to handle and transport. The transport and installation of the LHC cryo-magnets in the LEP tunnels originally designed for smaller, lighter LEP magnets has required development of completely new handling solutions. The paper explains the constraints imposed by the cryo-magnet characteristics, the existing tunnel infrastructure and schedule considerations. The development and realisation of transport and handling solutions are described, starting from conceptual design, through manufacture and testing to the installation of the first cryo-magnet. Integration studies to verify and reserve space needed for manoeuvre and the preparation of the infrastructure for transport and installation operations are also presented. The paper includes conclusions and some of the lessons learned.
|
|
|
||||||
WEPLT106 | Growth and Suppression Time of an Ion-related Vertical Instability | octupole, storage-ring, photon, betatron | 2098 | ||||||
|
In the KEK Photon Factory electron storage ring, a vertical instability has been observed in a multi-bunch operation mode. The instability can be suppressed by octupole magnetic field in routine operation. Since the instability depends on a vacuum condition in the ring, it seems that it is an ion-related phenomenon. In order to study this instability, we measured the growth and the suppression time of it with the pulse octupole magnet system, which can produce the octupole field with rise and fall time of around 1.2msec. We obtained the result that the instability was grown slowly compared with to suppress it, and the growth time depended on the fill pattern of the bunch train and the beam current per bunch.
|
|
|
||||||
THPLT070 | Design and Constriction of Coronagraph for Observation of Beam Halo | photon, background, optics, scattering | 2655 | ||||||
|
The coronagraph is a spatial telescope to observe the sun-corona by artificial eclipse. The concept of this apparatus is to realize the Schlieren-optical system for cutting the bright diffraction fringes in order to observe a less-bright object surrounding the main image such as the sun-corona. We applied this concept for the observation of the surrounding structure (halo, tail) of the beam. Since the background is mainly scattered light come from the objective lens, the key point to observe a less-intense object is to reduce scattering light from objective lens. We used a very well-polished lens (better than scratch and dig 20/20) as objective lens, and succeeded to obtain the signal to background ratio better than 10-5. As a test, we tried to observe the tail of beam by hiding the central peak with artificial eclipse by the coronagraph at Photon Factory storage ring. We succeeded to observe the tail of beam which has an intensity range of 1/104 of the peak intensity.
|
|
|
||||||
THPLT085 | Reengineering and Refactoring Large-scale Scientific Programs with the Unified Process: A Case Study with OSIRIS PIC Program | diagnostics, simulation, coupling, electromagnetic-fields | 2697 | ||||||
|
As science and engineering problems get more complex, programs which help modelling complicated problems larger and more sophisticated. This trend makes us recognize the importance of well-established engineering disciplines not only in designing large-scale scientific programs for special purposes in appropriate development time but also in importing the programs from other research group and refactor it for conveniences and more advanced applications. OSIRIS is a large-scale PIC code which was developed at UCLA for modelling of laser-plasma interactions. OSIRIS was reengineered and documented in UML by our group and ported to Linux cluster machine of 8 nodes. We report our current status of developing the extended version of OSIRIS, which was named as OSIRIS-X, and how a large-scale scientific programs can be enhanced efficiently with the Unified Process. Some guidelines in designing and refactoring large-scale scientific codes are presented and discussed. A common architecture model of numerically intensive programs for large-scale computing is suggested , and it is discussed how we can use it for rapid development and prototyping of scientific programs. We also discuss future challenges and prospects in OSIRIS-X development.
|
|
|
||||||
FRXBCH01 | Novel Ideas and R&D for High Intensity Neutrino Beams | proton, target, electron, storage-ring | 281 | ||||||
|
Recent developments in neutrino physics, primarily the conclusive demonstration of neutrino oscillations in both atmospheric neutrinos and solar neutrinos, provide the first conclusive evidence for physics beyond the Standard Model of particle physics. The phenomenology of neutrino oscillations, for three generations of neutrino, requires six parameters - two squared mass differences, 3 mixing angles and a complex phase that could, if not 0 or pi, contribute to the otherwise unexplained baryon asymmetry observed in the Universe. Exploring the neutrino sector will requires very intense beams of neutrinos, and needs novel solutions.
|
|
|
Video of talk
|
|
Transparencies
|
|