Beta Decays of Isotones with Neutron Magic Number of N=126 and R-process   Nucleosynthesis
  Beta decays of the isotones with N=126 are studied by shell model calculations taking into account both the Gamow-Teller (GT) and first-forbidden (FF) transitions. The FF transitions are found to be important to reduce the half-lives, by nearly twice to several times, from those by the GT contributions only. Possible implications of the short half-lives of the waiting point nuclei on the r-process nucleosynthesis during the supernova explosions are discussed. A slight shift of the third peak of the element abundances in the r-process toward higher mass region is found. 
Toshio Suzuki, Takashi Yoshida, Toshitaka Kajino and Takaharu Otsuka
nucl-th