Performance of a high speed and high density data acquisition system for multiple -ray detection

Kimura, Atsushi   ; Toh, Yosuke   ; Koizumi, Mitsuo ; Furutaka, Kazuyoshi  ; Kin, Tadahiro; Oshima, Masumi

In order to measure neutron capture cross sections with time of flight method and multiple -rays coincidence method, the present authors decided to construct a large Ge detector array at MLF in the J-PARC project. Time-integrated neutron flux in thermal region at the MLF is expected to be 1.110 n/s/cm. Because of the high neutron flux, the DAQ reported in NSS 2004 can not handle the signals from the spectrometer. The authors, therefore, have improved the DAQ and report performance of our system in this NSS 2008. Total energy resolution of this system was 2.4 keV in FWHM for 1.33-MeV -rays. The dead time of this system is only 3.3 s per event and the maximum event rate was more than 300 k events/s.