Hajima, R.

Paper	Title	Page
WG212	Space Charge Compensation and Optimal Mergers for ERL Injectors
	R. Hajima JAEA/ERL, Ibaraki
	Emittance growth and its compensation at an ERL injector is one of key issues for future ERL light sources. We overview the sources of emittance growth and the way to compensate them. We also discuss the emittance dilution at a merger, which has never been studied in non-ERL accelerators.
	Slides
WG205	Status of the ERL Projects at KEK and JAEA
	S. Sakanaka KEK, Ibaraki R. Hajima JAEA/FEL, Ibaraki-ken
	Two Japanese institutes, the High Energy Accelerator Research Organization (KEK) and the Japan Atomic Energy Agency (JAEA; formerly JAERI and JNC), proposed each own 5-6 GeV ERL project for the future light source. Thereafter, the two institutes agreed to promote an ERL-based next-generation synchrotron light source in Japan based on their stimulated technologies. As a first step towards this course, KEK and JAEA are planning to construct together an ERL test facility at KEK site in order to resolve technical and physical challenges. The ERL test facility will comprise a 5-10 MeV injector, a superconducting main linac, and a return loop. The beam energy of the main linac will initially be a few tens of MeV, and will be upgraded up to about 200 MeV. We are also promoting cooperation with the other Japanese SR facilities, SPring-8, UVSOR, and ISSP, to organize an R&D team for the ERL test facility. We present current status and plans of the KEK-JAEA ERL project.
	Slides
WG221	Vacuum and Aperture Needs for Energy-Recovery Linac Light Sources
	R. Hajima JAEA/FEL, Ibaraki-ken
	Vacuum and aperture are general issue in all particle accelerators. Smaller aperture is beneficial for economical design of magnets, but harmful for good vacuum. In the design of storage-ring light sources, vacuum and aperture are crucial points to discuss, because the beam lifetime is mainly determined by beam-residual gas interactions. Vacuum and aperture needs for ERL light sources are not same as storage rings. In this talk, we examine vacuum and aperture needs for energy-recovery linacs from viewpoints of beam loss, ion trapping, shielding of coherent synchrotron radiation, etc.
	Slides