Author: Kaneyasu, T.
Paper Title Page
TUPO014 High-flux Gamma-ray Generation by Laser Compton Scattering in the SAGA-LS Storage Ring 1476
 
  • T. Kaneyasu, Y. Iwasaki, S. Koda, Y. Takabayashi
    SAGA, Tosu, Japan
  
  We con­struct­ed an ex­per­i­men­tal setup for high-flux gam­ma-ray gen­er­a­tion by laser Comp­ton scat­ter­ing (LCS) in the SAGA-LS stor­age ring. The SAGA-LS is a syn­chrotron ra­di­a­tion (SR) fa­cil­i­ty con­sist­ing of a 255 MeV in­jec­tor linac and a 1.4 GeV stor­age ring. We em­ployed a CO2 laser hav­ing a wave­length of 10.6 mi­crom­e­ter to pro­duce gam­ma-rays in the few MeV re­gion in con­junc­tion with the SR user time. The LCS gam­ma-ray up to the max­i­mum en­er­gy of 3.5 MeV is gen­er­at­ed via head-on col­li­sion be­tween the laser pho­tons and the 1.4 GeV stored beam. Since the en­er­gy ac­cep­tance of the stor­age ring is well above the max­i­mum gam­ma-ray en­er­gy, the LCS ex­per­i­ment can be per­formed with­out re­duc­ing the beam life­time. As a first step for high-flux gam­ma-ray gen­er­a­tion, we use a small 10 W CO2 laser for beam test. The LCS event rate is de­signed to be 2·108 ph/s with a beam cur­rent of 300 mA and a laser power of 10 W. A fur­ther in­crease of the LCS event rate in the order of 1010 ph/s is ex­pect­ed when a kW class laser is uti­lized. We re­port on the char­ac­ter­is­tics of the LCS gam­ma-rays ob­served in the low cur­rent beam test and an ex­per­i­men­tal re­sult for eval­u­at­ing the gam­ma-ray flux at a cur­rent of 300 mA.  
 
THPC042 Status and Development of the SAGA Light Source 2996
 
  • T. Kaneyasu, Y. Iwasaki, S. Koda, Y. Takabayashi
    SAGA, Tosu, Japan
  
  The SAGA Light Source (SAGA-LS) is a syn­chrotron ra­di­a­tion fa­cil­i­ty con­sist­ing of a 255 MeV in­jec­tor linac and a 1.4 GeV stor­age ring, and has been sta­bly pro­vid­ing syn­chrotron light since 2006. The an­nu­al fail­ure time is less than 1% of the user time in the re­cent two years. Three in­ser­tion de­vices are in­stalled in the stor­age ring: an AP­PLE-II un­du­la­tor, a pla­nar type un­du­la­tor (Saga Univ.) and a 4 T su­per­con­duct­ing wig­gler (SCW). The SCW con­tains a hy­brid three-pole mag­net; the main pole of the mag­net is sur­round­ed by su­per­con­duct­ing coils while side poles are nor­mal con­duct­ing mag­nets. The main pole of the SCW is cooled by a GM cry­ocool­er, which al­lows the SCW be op­er­at­ed with­out liq­uid he­li­um. Since the in­stal­la­tion in March 2010, the SCW has been op­er­at­ed sta­bly. To con­trol the ID pa­ram­e­ters dur­ing the user time, a feed-for­ward cor­rec­tion sys­tem which min­i­mizes the ID ef­fects on the emit­tance cou­pling was de­vel­oped. The laser Comp­ton Gam­ma-rays were gen­er­at­ed by using a CO2 laser and were used for beam en­er­gy mea­sure­ment. In ad­di­tion, re­search works on the beam life­time and in­ter­ac­tion be­tween elec­tron beam and crys­tal, and de­vel­op­ment of a mul­ti­pole mag­net are in progress.