Development of total absorption detector using clover detector for measurements

Hayashi, Hiroaki*; Shibata, Michihiro*; Asai, Masato  ; Osa, Akihiko  ; Oshima, Masumi; Kimura, Atsushi   ; Koizumi, Mitsuo ; Sato, Tetsuya   

A new total absorption detector composed of a large Clover-type Ge detector and BGO Compton suppressors has been developed to measure values of nuclei far from the -stability line. The Clover detector has a through-hole with a 15-mm inner diameter at its center to put radioactive sources in it. Because of its high detection efficiencies for both and rays, the value can be directly determined from the endpoint of an observed total sum spectrum for and rays without information on the decay scheme. Using this detector, values of Eu and Gd produced in the proton-induced fission of U and mass-separated by an on-line isotope separator at the JAEA-Tokai Tandem Accelerator have been determined with accuracies of 30-300 keV.