KEK, Ibaraki
ISSP/SRL, Chiba
TIPC, BeiJing
A new vertical test facility for L-band multi-cell cavities has been completed in support of development efforts of ILC (International Linear Collider) and ERL (Energy Recovery Linac) projects at STF (Superconducting rf Test Facility) of KEK. The facility possesses a clean booth for pre-tuning the cavities, four cavity stands to prepare the cavities prior to vertical testing, a half-underground pit which accommodates up to two vertical cryostats which can be pumped and operated separately under a movable iron shield. Vertical testing of the cavities, with a 400 W high-power amplifier and with a temperature-mapping (T-mapping) and additional monitoring systems, is supervised from a control room which overlooks the entire facility. This paper describes the specific details of the facility and results from its initial pilot operation that was conducted in Summer-Fall of 2008.
KEK, Ibaraki
ISSP/SRL, Chiba
TIPC, BeiJing
A new cavity diagnostic system has been introduced for vertical testing of nine-cell L-band superconducting cavities at KEK-STF. The present system is based on approximately 300 carbon resistors for temperature-mapping (T-mapping), and approximately 40 PIN photo diodes for detecting emission of X-rays. The system can accommodate up to total 600 sensors in needed in the future. While most of the sensors are attached to the cavity exterior in a pre-determined regular pattern, some sensors can be strategically placed at non-regular positions so as to watch the areas which are considered “suspicious” as per the surface inspection done prior to vertical testing. Data from the sensors can be collected every 100 msec. The data can be graphically displayed online and are stored for offline analysis. This paper describes the details of this system, together with results from its initial pilot operation which was done with a nine-cell cavity on loan from FNAL (AES#001). Effectiveness of the combined use of T-mapping and PIN photo diodes in operation of the pi-mode and other pass-band modes in conjunction with surface inspection is discussed.
KEK, Ibaraki
JAEA/ERL, Ibaraki
JASRI/SPring-8, Hyogo-ken
ISSP/SRL, Chiba
UVSOR, Okazaki
HU/AdSM, Higashi-Hiroshima
Hiroshima University, Graduate School of Science, Higashi-Hiroshima
AIST, Tsukuba
Future synchrotron light source project using an energy recovery linac (ERL) is under proposal at the High Energy Accelerator Research Organization (KEK) in collaboration with several Japanese institutes such as the JAEA and the ISSP. We are on the way to develop such key technologies as the super-brilliant DC photo-injector and superconducting cavities that are suitable for both CW and high-current operations. We are also promoting the construction of the Compact ERL for demonstrating such key technologies. We report the latest status of our project, including update results from our photo-injector and from both superconducting cavities for the injector and the main linac, as well as the progress in the design and preparations for constructing the Compact ERL.
KEK, Ibaraki
Two synchrotron light sources of the Photon Factory storage ring (PF-ring) and the Photon Factory advanced ring (PF-AR) have been stably operated at KEK. PF-ring covers the photon-energy range from VUV to hard X-ray using a 2.5 GeV (sometimes 3.0 GeV) electron beam. PF-AR is mostly operated in a single-bunch mode of 6.5GeV to provide pulsed hard X-rays. Recently, the operation has progressed to realize a so-called top-up injection at PF-ring. In a single-bunch mode, the continuous injection to preserve a constant beam current of 51 mA has been carried out since February 2007. In addition, the injection with continuing the experiments has been successfully operated in a multi-bunch mode since October 2008. At PF-AR, sputter ion pumps have been extensively reinforced to prolong the beam lifetime and to reduce the frequency of sudden lifetime drops by substituting for distributed ion pumps, which are considered as one of the dust sources. In this conference, we present the recent progress of the operation at PF-ring and PF-AR including machine developments.
CLASSE, Ithaca, New York
LBNL, Berkeley, California
KEK, Ibaraki
ANL, Argonne
Fermilab, Batavia
CalPoly, San Luis Obispo, CA
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
SLAC, Menlo Park, California
Cornell University, Ithaca, New York
Cockcroft Institute, Warrington, Cheshire
Funding: Support provided by the US National Science Foundation, the US Department of Energy, and the Japan/US Cooperation Program.
In March of 2008, the Cornell Electron Storage Ring (CESR) concluded twenty eight years of colliding beam operations for the CLEO high energy physics experiment. We have reconfigured CESR as an ultra low emittance damping ring for use as a test accelerator (CesrTA) for International Linear Collider (ILC) damping ring R&D. The primary goals of the CesrTA program are to achieve a beam emittance approaching that of the ILC Damping Rings with a positron beam, to investigate the interaction of the electron cloud with both low emittance positron and electron beams, to explore methods to suppress the electron cloud, and to develop suitable advanced instrumentation required for these experimental studies (in particular a fast x-ray beam size monitor capable of single pass measurements of individual bunches). We report on progress with the CESR conversion activities, the status and schedule for the experimental program, and the first experimental results that have been obtained.
