| Paper | Title | Page |
|---|---|---|
| MO6PFP018 | The Pulsed Magnet System for the Simultaneous Injection of KEK-PF and KEKB Ring | 172 |
|
||
|
The KEK Linac delivers the beam to KEK-Photon factory storage ring, KEKB ring and the advanced ring for photon factory. In order to deliver the beam to the KEK-photon factory and KEKB ring simultaneously, the pulsed bending magnet was installed at the end of KEKB Linac. The pulsed bending magnet extract 2.5GeV electron beam to the PF beam transfer line. The deflection angle of the magnet is 0.114 radians and the field strength is almost 1.22T. The peak current stability is better than 0.1% at 24kA operation. The maximum repetition rate is 25Hz. The 1.2m long ceramic chamber is inserted into the 1m long magnet. This system makes possible the top up operation of PF ring. |
||
| MO6RFP067 | Beam Dynamics Simulation for the Compact ERL Injector | 521 |
|
||
|
The compact ERL, cERL, is a project to test an energy recovery linac (ERL) with 60 MeV and 100 mA electron beam to generate synchrotron radiation with smaller emittance and shorter pulse length. The design work of the cERL injector has been carried out using a space charge simulation code. The injector consists of 500 kV photo cathode DC gun, two solenoid magnets, buncher cavity, three super conducting RF cavities and merger section to return pass. It generates an electron beam with -77 pC bunch charge and 1.3 GHz repetition rate. Our target value of emittance is less than 1 mm mrad with the bunch length of 1 mm at the exit of the injector. The parameter optimization of the injector using the multi objected method has been carried out to obtain the minimum emittance. The simulation results will be presented in detail. |
||
| MO6RFP074 | Design and Fabrication of a 500-kV Photocathode DC Gun for ERL Light Sources | 542 |
|
||
|
A 500-kV, 10-mA photocathode DC gun has been designed and is now under fabrication by the collaboration efforts of JAEA, KEK, Hiroshima Univ. and Nagoya Univ. The Cockcroft-Walton generator and the ceramic insulator are installed upright in the SF6 tank. We have adopted a multiple-stacked cylindrical ceramic insulator, because this type of ceramic insulator has shown good stability and robustness at the 200-kV Nagoya polarized gun and the 250-kV JAEA FEL gun. All the vacuum chambers are made of titanium alloy with very low out-gassing. The Cockcroft-Walton generator, the ceramic insulator, the vacuum chambers will be fabricated by April 2009 and a high-voltage test will be started soon later. Up-to-date status of the gun development will be presented in detail. |
||
| MO6RFP075 | Development of a 250-kV Photo-Cathode Electron Gun for the ERL Light Sources at JAEA | 545 |
|
||
|
A 250-kV, 50-mA electron gun has been developed at JAEA for establishing fundamental technologies to generate and evaluate a ultra-small emittance beam, which is required for future ERLs such as a coherent X-ray source and a high-flux gamma-ray source. The gun has been assembled and the first photo-current was obtained from a cathode of NEA-GaAs. Apparatuses for beam measurements has been installed. We plan to measure the transverse emittance by a double-slit configuration and the temporal profile with a deflecting cavity. |
||
| TU5RFP084 | Beam Optics Study for the Compact ERL in Japan | 1284 |
|
||
|
A compact ERL (energy recovery linac) is planned in Japan in order to demonstrate excellent ERL performances and to test key components such as low-emittance photocathode gun and superconducting RF cavity. We studied and optimized the compact ERL optics (except the injector part) to generate a subpico-second bunch in bunch compression mode and to preserve the beam emittance in normal and low-emittance mode. As a result, we could obtain a very short bunch of about 50 fs with a charge of 77 pC in bunch compression mode and almost keep the normalized emittance of 0.1 mm mrad with a charge of 7.7 pC in low-emittance mode. We also designed it to achieve efficient energy recovery at the superconducting RF cavities and to transport the beam to the dump section without serious loss. The design study of the compact ERL optics was carried out with the simulation code Elegant, including CSR(coherent synchrotron radiation) effects. In this paper, we will present the results of the beam optics study for the compact ERL. |
||
| TU6RFP045 | Stored Beam Stability during Pulsed Sextupole Injection at the Photon Factory Storage Ring | 1647 |
|
||
|
We successfully demonstrated a new beam injection method using a single pulsed sextupole magnet (PSM). The PSM has a parabolic-shaped magnetic field, which is expected to provide an effective kick to the injected beam without little effects on the stored beam. We installed the PSM injection system at the Photon Factory storage ring (PF-ring) and succeeded in injecting the beam into PF-ring and storing the current up to 450 mA. This is the first demonstration of the PSM beam injection in electron storage rings. We also tested top-up injection and confirmed that dipole oscillation of the stored beam was sufficiently reduced compared with that generated by the conventional injection system. In this conference, we will present the experimental results and the advantages of the PSM beam injection. |
||
| WE5RFP072 | Fast Local Bump System for the Helicity Switching at the Photon Factory | 2429 |
|
||
|
A fast local bump system for the helicity switching of a circular/linear polarized undulator (CPU) has been developed at the Photon Factory storage ring (PF-ring). The system consists of five identical bump magnets and tandem APPLE-2 type CPUs. In addition, fast correction magnets for a leakage of the bump were prepared. We designed the bump magnets with a core length of 0.15 m, a pole gap of 21 mm and the coils of 32 turns, which were excited by bipolar power supplies with a capacity of ±100 A and ±50 V since a switching frequency of more than 10 Hz and a bump angle of 0.3 mrad were required for user experiments. The bump magnets and one of CPUs were installed at PF-ring in March 2008, and the experiments for the machine development using a stored beam have been progressed. In this conference, we present the first experimental results with the bump system. |
||
| TU5RFP031 | Recent Progress of the Operation at PF-Ring and PF-AR | 1165 |
|
||
|
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. |
||
| TU5RFP081 | Status of the Energy Recovery Linac Project in Japan | 1278 |
|
||
|
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. |