Shintake, T.
(Tsumoru Shintake)

MOBIS01 Overview of Single Pass FEL Designs Technical Suggestions for Stability Improvement
Tsumoru Shintake (RIKEN Spring-8 Harima, Hyogo)

The talk will review recent achievement of technology development for SASE-FELs, such as the low emittance electron sources. The talk also gives some suggestion on "Background technology requirement for Single Pass FELs before or behind the "low emittance" story. Question is what do we need to prepare before starting the construction of a large scale machine?

THBOC03 Emittance Measurement on the CeB6 Electron Gun for the SPring-8 Compact SASE Source
Kazuaki Togawa, Hitoshi Baba, Takahiro Inagaki, Kazuyuki Onoe, Tsumoru Shintake, Takashi Tanaka (RIKEN Spring-8 Harima, Hyogo), Hiroshi Matsumoto (KEK, Ibaraki)

A high-volatage pulsed electron gun has been constructed for the injector system of the soft X-ray FEL project at SPring-8 (SCSS project). A CeB6 single crystal was chosen as a thermionic cathode, because of its excellent emission properties. The gun voltage of -500 kV was chosen to reduce emittance growth due to space charge. We have succeeded in generating a 500 keV beam with 1 A peak current and 3 micro-sec FWHM. The beam was very stable with low jitter. The beam emittance has been measured by means of double-slits method, and the normalized rms emittance of 1.1 pi-mm-mrad has been obtained. We report on the experimental result on the emittance measurement of the CeB6 electron gun.

MOPOS21 Seeding High Gain Harmonic Generation with Laser Harmonics Produced in Gases
Guillaume Lambert, Bertrand Carré, Yann Mairesse, Pascal Salières (CEA/Saclay, Gif-sur-Yvette), Marie-Emmanuelle Couprie, David Garzella (CEA/SPAM, Gif-sur-Yvette), Andrea Doria, Luca Giannessi (ENEA C.R. Frascati, Frascati - Roma), Toru Hara, Hideo Kitamura, Tsumoru Shintake (RIKEN Spring-8, Hyogo)

Free electron Lasers employing High Gain Harmonic generation (HGHG) schemes are very promising coherent ligth sources for the soft X-ray regime. They offer both transverse and longitudinal coherence, while Self Amplified Spontaneous Emission schemes have a longitudinal coherence 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. Semi analytical , numerical 1D and 3D calculations are given, for the cases of the SCSS, SPARC and ARC-EN-CIEL projects.

TUPOS20 Electron Beam Simulations on the SCSS Accelerator
Toru Hara, Hideo Kitamura, Tsumoru Shintake (RIKEN Spring-8 Harima, Hyogo)

The SPring-8 Compact SASE Source (SCSS) is a SASE-FEL project aiming at soft X-ray radiation at its first stage using 1 GeV electron beams. One of the unique features of the SCSS is the use of a pulsed high-voltage electron gun with a thermionic cathode. Main reason for this choice is its high stability and the well developed technology relating to the gun. Meanwhile, the electron bunch should be compressed properly at the injector in order to obtain sufficient peak currents. In this presentation, the results of the electron beam simulations along the accelerator and the expected parameters of the electron beam will be given.