Study on presolar grain using neutron activation analysis with multiple ray detection

Hatsukawa, Yuichi; Miyamoto, Yutaka   ; Toh, Yosuke   ; Oshima, Masumi; Hayakawa, Takehito

We developed a new technique of trace element analysis based on neutron activation analysis with coincident -ray detection. In order to improve the low efficiency of coincident -ray detection, an array of 16 Ge detectors with BGO Compton suppressors was used for this method. High sensitive trace element analyses without chemical separation were carried out by the combination of neutron activation analysis and the method of multiparameter coincidence spectroscopy. In this study, we try to measure trace elements in presolar grains using neutron activation analysis with multiple ray detction. Presolar grains are synthesis in stars such as the Super nova or Red giant, and found in the primitive meteorites. We obtained 160 micro grams of nanodiamonds which is one of presolar grains from the Allende meteorite, and measured trace elements in the grains using this method. 8 elements in presolar grain were detected.