Author: Kuroda, R.
Paper Title Page
THPWA014 Development of Photon-induced Positron Annihilation Lifetime Spectroscopy using an S-band Compact Electron Linac 3660
  • Y. Taira, R. Kuroda, B.E. O'Rourke, N. Oshima, R. Suzuki, M. Tanaka, H. Toyokawa
    AIST, Tsukuba, Ibaraki, Japan
  • K. Watanabe
    Nagoya University, Nagoya, Japan
  • T. Yanagida
    Kyushu Institute of Technology, Fukuoka, Japan
  Funding: This work was supported by Grants-in-Aid for Scientific Research (22360297)
Positron annihilation lifetime spectroscopy (PALS) is a very sensitive tool to characterize materials and study defects at the nanometer scale. However, the application of PALS has been restricted to thin samples because of the limited range of positrons in materials. PALS for thick samples is possible by using high energy photons to create positrons inside the sample via pair production. This technique is called photon-induced positron annihilation lifetime spectroscopy (PiPALS). We have developed a novel PiPALS system using ultra-short photon pulses based on bremsstrahlung radiation to carry out in-situ measurement of structural materials under special conditions (piping for supercritical water and nuclear reactor materials). Intense, ultra-short photon pulses with energies up to 40 MeV can be generated by using an electron linear accelerator with photocathode rf gun system at AIST. In this conference, we will present the experimental result of the positron annihilation lifetime spectrum of a metal target by using ultra-short photon pulses*.
*Y. Taira et al., Rad. Phys. and Chem., accepted for publication 2012.