Kitamura, H.

Paper	Title	Page
MOPKF029	Seeding High Gain Harmonic Generation with Laser Harmonics produced in Gases	363
	G. Lambert, B. Carré, M.-E. Couprie, D. Garzella CEA/Saclay, Gif-sur-Yvette A. Doria, L. Giannessi ENEA C.R. Frascati, Frascati (Roma) T. Hara, H. Kitamura, T. Shintake RIKEN Spring-8 Harima, Hyogo
	Free electron lasers employing High Gain Harmonic Generation (HGHG) schemes are very promising coherent light sources for the soft X-ray regime. They offer both transverse and longitudinal coherence, inversely to Self Amplified Spontaneous Emission schemes, where the longitudinal coherence is limited. We propose here to seed HGHG with high harmonics produced by a Ti:Sa femtosecond laser focused on a gas jet, tuneable in the 100-10 nm spectral region. Specifities concerning the implementation of this particular laser source as a seed for HGHG are investigated. Theoretical ad numerical calculations (using PERSEO in particular) are given, for the cases of the SCSS and ARC-EN-CIEL projects.
TUYBCH01	Design Criteria and Technology Challenges for the Undulators of the Future	59
	H. Kitamura, T. Hara, X. Maréchal, T. Tanaka RIKEN Spring-8 Harima, Hyogo T. Bizen, T. Seike JASRI/SPring-8, Hyogo
	Nowadays, undulators are essential devices for synchrotron radiation (SR) facilities since they generate a quasi-monochromatic radiation with various features, high brightness , high energy and special polarization characteristics. Particularly, demands for high-energy radiation in the X-ray region have become much stronger in many research fields. Accordingly, a short-period undulator design has been developed, because they increase the number of periods in a unit undulator length and as a consequence, they generate brilliant synchrotron radiation. Also, short undulator periodicity enables emission of high-energy photons, and it opens the way for X-ray beamline operation in medium size synchrotron radiation facilities, such as SLS, NSLS, PLS, CLS, ALS, SOLEIL, DIAMOND, SPEAR-III and so on. From the same reason, a short-period undulator is very attractive for SASE-FEL or ERL facilities, since it lowers the electron beam energy necessary for X-ray operation. As a result this design makes a whole facility design compact and economic. In the talk, I will review the status of the development on short-period undulators of various types (in-vacuum, superconducting and cryogenic types) and describe the future direction.
	Video of talk
	Transparencies
WEPLT103	Radiation Damage in Magnets for Undulators at Low Temperature	2089
	T. Bizen, X. Maréchal, T. Seike JASRI/SPring-8, Hyogo Y. Asano JAERI/SPring-8, Hyogo T. Hara, H. Kitamura, T. Tanaka RIKEN Spring-8 Harima, Hyogo D.E. Kim, H.S. Lee PAL, Pohang
	Nd2Fe14B permanent magnets are used in many insertion devices for its good magnetic and mechanical properties. However, the radiation sensitivity of the magnets would be concern when they are used in a strong radiation environment. It is known that these magnets with very high coercivity show high resistance to radiation, though the substance for increasing the coercivity decrease the remanence. The coercivity and remanence of this magnet exhibit negative dependence against temperature, so it is expected to these magnets to show high remanence and high resistance to radiation at low temperature. The idea of using magnets at low temperature leads the new concept of the cryogenic undulators. In this report, the experimental results of the radiation damage of permanent magnets at low temperature are shown.