• T. Tanaka
  RIKEN Spring-8, Hyogo
• Y. Asano
  JAEA, Ibaraki-ken
• H. Baba, T. Bizen, Z. Chao, H. Ego, S. Eguchi, S. Goto, T. Inagaki, S. Inoue, D. Iwaki, K. Kase, Y. Kawashima, H. Kimura, S. Kojima, T. Kudo, N. Kumagai, X. Marechal, S. Matsui, T. Ohata, K. Onoe, Y. Otake, T. Seike, K. Shirasawa, N. Shusuke, T. Takagi, T. Takashima, K. Tamasaku, R. Tanaka, K. Togawa, R. Tsuru, S. Wu, M. Yabashi, S. Yoshihiro
  JASRI/SPring-8, Hyogo
• T. Fukui
  Kyoto IAE, Kyoto
• T. Hara, T. Ishikawa, H. Kitamura, T. Shintake
  RIKEN Spring-8 Harima, Hyogo
• H. Matsumoto
  KEK, Ibaraki
• S. Takahashi
  LNS, Sendai

Funding: Representing the SCSS project team

SCSS, an acronym of "SPring-8 Compact SASE Source", is an X-ray FEL project under planning to be build at the SPring-8 site. R&Ds for accelerator components such as the pulsed-DC electron gun, C-band main linac, and in-vacuum short period undulator have been performed and almost completed. Before construction of the X-ray FEL facility, a prototype accelerator with the electron energy of 250 MeV is being built to demonstrate the concept of SCSS. In this presentation, status of the R&Ds for each accelerator component will be presented together with an overview of the 250-Mev prototype accelerator.

• Y. Tsunawaki
  OSU, Daito, Osaka
• M. Asakawa, N. Ohigashi
  Kansai University, Osaka
• K. Imasaki
  ILT, Suita, Osaka

We have been constructed a solenoid-induced helical wiggler for a compact free electron maser operated in a usual small laboratory which does not have electric source capacity available enough. It consists of two staggered-iron arrays inserted perpendicularly to each other in a solenoid electromagnet. In order to lead/extract an electron beam into/from the wiggler, adiabatic transition (AT) field is necessary at both ends of the wiggler. In this work the AT field was produced by setting staggered-nickel plates with different thickness in the five periods. The thickness of each nickel plate was decided by the field analysis using the MAGTZ computational code based on a magnetic moment method. Exact thickness was, however, found by the precise measurement of the field distribution with the greatest circumspection to obtain a homogeneous increment of the AT field. The change of AT field distribution was studied by referring to an equivalent electric circuit of the wiggler.

• L. Catani, E. Chiadroni, A. Cianchi
  INFN-Roma II, Roma
• M. Castellano, G. Di Pirro, D. Filippetto, C. Vicario
  INFN/LNF, Frascati (Roma)
• M.V. Hartrott
  BESSY GmbH, Berlin
• M. Krasilnikov, A. Oppelt, F. Stephan
  DESY Zeuthen, Zeuthen

For the SPARC Project a novel diagnostic device, called "Emittance-meter", has been conceived and constructed to perform a detailed study of the emittance compensation process in the SPARC photo-injector and to optimize the RF-gun and the accelerator working point. It consists of a movable emittance measurement system, based on the 1D pepper-pot method, installed between two long bellows with the possibility to scan a region 1.5 m long downstream the RF-gun. The construction of the device was completed in the first part of this year and a series of laboratory tests, to evaluate its performances, were carried out in Spring 2005. At the beginning of the summer the complete system was moved to DESY at Zeuthen to be installed on the Photo Injector Test Facility PITZ. After the commissioning it will used for measurements of the PITZ electron beam in the framework of a collaboration between the SPARC and PITZ Projects aiming on studies and operations with photo injectors.