• K. Koyama, A. Yamazaki
  UTNL, Ibaraki
• T. Hosokai
  RLNR, Tokyo
• A. Maekawa, M. Uesaka
  The University of Tokyo, Nuclear Professional School, Ibaraki-ken
• M. Miyashita
  SUT, Noda-shi, Chiba

An all-optical inverse Compton gamma-ray source is enable us to make a tabletop monochromatic gamma-ray source that might be applied to measure an amount of nuclear material, etc. An intense laser pulse excites a very nonlinear plasma wave and accelerate electron bunch up to several-hundreds MeV within a length of a few millimeters. The key to success is stabilization of the laser-plasma accelerators. We are developing the artificial injection technique of initial electrons in to the plasma wave and guiding of the intense laser pulse by the preformed plasma channel.