Laser Compton scattering gamma rays generated in NewSUBARU and to use applied research in pair production positrons

We developed the MeV order gamma ray source by Laser Compton scattering (LCS) at NewSUBARU BL01. Yb fiber laser (1064 nm) and an Er fiber laser (1550 nm) are newly introduced. The LCS-gamma fluxes are 1.0×10³ photon/mA/W/s and 2.0×10² photon/mA/W/s with gamma ray energy of 17 MeV and 11 MeV, using the Yb laser and the Er laser, respectively. These gamma ray beams are collimated by two collimators of 6 mm in diameter. The output pulses of these two lasers are possible to synchronize with the electron bunches of 30ps pulse width in NewSUBARU storage ring. This system will be applicate to the experiments required high time resolution. Generated MeV order gamma rays will be applied for generation of high energy positrons by pair creation. Lifetime measurement will be developed for non-destructive material inspection by high energy positron. (author)