Beta-decay measurement of Cr

若林 泰生; 山口 英斉*; 橋本 尚志*; 早川 勢也*; 栗原 佑蔵*; Binh, D.*; Kahl, D.*; 久保野 茂*; 西村 俊二*; 郷農 靖之*; et al.

no journal, , 

For the rapid proton capture process (-process) in X-ray bursts and the core-collapse stage of supernovae, proton-rich -shell nuclei far from the line of stability play important roles. Studies of the feeding ratios and half-lives of the and electron capture decays of these proton-rich -shell nuclei are of great astrophysical interest not only for nucleosynthesis but also for Fermi and Gamow-Teller transition study. The experiment to measure the half life of decay of Cr was performed using the low-energy RI beam separator (CRIB) of the Center for Nuclear Study (CNS), University of Tokyo. The Cr particles were produced by the Ar + C fusion reaction. A natural C foil of 0.56 mg/cm was installed as the primary target. The Ar primary beam was accelerated up to 3.6 MeV/nucleon by the RIKEN AVF cyclotron. A double sided Si strip detector (DSSD) of 500-m thickness was used as a -ray detector. A Si detector of 1.5-mm thickness was placed just behind the DSSD for a -ray detector. To measure -delayed rays, 3 clover and 1 coaxial Ge detectors were set around the target chamber. The beam was pulsed to measure the half life of the decay of Cr. The -delayed ray of Cr was observed in this experiment. The experimental result will be discussed.