Development of Global Ionizing Radiation Monitoring Net-work

Replacement of CsI(Tl) / PD with SrI₂(Eu) / MPPC

Abstract

Development of the global ionizing radiation monitoring network (GIRMN) system has progressed significantly by the use of SrI₂(Eu)-scintillator which has excellent material properties for γ-ray spectroscopy; high light yield (>80,000 ph/MeV), excellent light yield proportionality, high photo electric cross-section, etc. The high energy resolution (<4 %) and high sensitivity of the SrI₂(Eu)-scintillator of 25mmφ × 25 mm high supplied by Union Materials Inc. Japan allows to discriminate the Cs originated γ-rays from the other nucleus species. The software platform newly adopted in the GIRMN is based on the use of ANSI N4242 Data File Format published by NIST and is, therefore, expected to afford the requirements for the standardization and sustainability as a standard ionizing radiation monitoring.