| Paper | Title | Page |
|---|---|---|
| MOZAKI01 | Compensation of the Crossing Angle with Crab Cavities at KEKB | 27 |
|
||
|
The crab cavities are presently being installed in the KEKB rings to compensate the crossing angle at collision and thus increase luminosity. This will be the first experience with such cavities in colliders. Results on the beam operation of the new cavities, both for single and colliding beams, will be presented including the luminosity performance and limitations.
Work presented on behalf of the KEKB Accelerator Group. |
||
|
Slides | |
| MOPAN037 | Acceleration of Cold Emission Beam from Carbon Nanotube Cathode in KEKB/PF Linac | 236 |
|
||
| An electron gun with carbon nanotube cathode has been installed in the KEKB/PF linac, and the beam acceleration tests up to 2.5GeV have been performed successfully. The results and performance are presented in details. | ||
| WEPMN036 | High Field Performance in Reduced Cross-sectional X-Band Waveguides Made of Different Materials | 2119 |
|
||
| To study the characteristics of different materials on high-field rf breakdown we designed a simplified waveguide, where the field of 200MV/m is realized at rf power of 100MW. The geometry is transformed from the WR90, where the height and the width are reduced from 10.16 mm to 1mm and from 22.86mm to 14mm, respectively. This paper reports on the high-gradient testing of copper and stainless-steel waveguides. We have observed rf breakdowns by bursts of x-rays, flashes of visible lights and acoustic signals. Frequent breakdowns are observed at about 100MV/m level in copper case and the study on the stainless-steel waveguide will be performed to be compared to that of copper case. | ||
| THPMN027 | Status of C-band Accelerator Module in the KEKB Injector Linac | 2769 |
|
||
| For future upgrade of the KEKB injector linac, components of C-band accelerator module have been developed since 2002. A prototype C-band accelerator module composed of a 50-MW klystron, an RF-pulse compressor and four 1-m long accelerating sections, has been constructed in the present S-band injector linac. It has been operated for 14 months. In a recent beam-acceleration study, it has achieved an energy gain of 151 MeV, which corresponds to an average acceleration field of 39 MV/m. | ||
| THPMN029 | A DC/Pulse Electron Gun with an Aperture Grid | 2775 |
|
||
| A new thermionic-electron gun for a high-brightness X-ray source is under development. Its extraction voltage and design current are 60 keV and 100 mA, respectively. In order to focus beams on a metal target within 1.0 x 0.1 mm2, it is required for the emittance of a beam to be small. A grid electrode is not an orthodox mesh grid but an aperture grid. An increase of the beam emittance and heat generation at a grid will be surpressed. Electrodes dimensions such as shape of Wehnelt electrode and a shape of an aperture grid are determined by the EGUN simulation and parameters were optimized. In this paper a result of beam examination will be reported. | ||
| TUPMN044 | Status of R&D Efforts Toward the ERL-based Future Light Source in Japan | 1016 |
|
||
| Energy Recovery Linacs (ERL), based on superconducting accelerators, are one of the most promising synchrotron light sources in future. The KEK and the JAEA, in collaboration with the ISSP, the UVSOR, and the SPring-8, are considering to realize together the ERL-based next-generation light source in Japan. To establish key technologies for that, active R&D efforts started. The R&D program includes the developments of ultra-low-emittance photocathode guns and of superconducting cavities, as well as experimental proofs of accelerator-physics issues at the ERL test facility, which will be built at the KEK campus. We are currently working on constructing a prototype photocathode gun, on designing superconducing cavities, and on designing a prototype ERL. The current plan of the prototype ERL comprises a full injector linac, one or two cryomodules for the main linac, and the beam return loop, which can be operated at beam energies from 60 to 160 MeV. The up-to-date R&D status will be reported. | ||
| TUPAN045 | Beam Operation with Crab Cavities at KEKB | 1487 |
|
||
|
Beam operation with crab cavities is planned in early 2007 at KEKB. The crab crossing scheme is expected to increase the vertical beam-beam tune-shift parameter significantly. One crab cavity will be installed in each ring where conditions for beam optics are matched to compensate the beam crossing angle of 22 mrad. Operation results on collision tuning with the crab cavities will be presented.
For the KEKB Accelerator Group. |