Beta-decay half-lives of new neutron-rich chromium-to-nickel isotopes and their consequences for the astrophysical r-process

Abstract Beta-decay studies of the new neutron-rich isotopes 58,59 Cr, 63 Mn, 66,67 Co and 69 Ni, yielding distinctly shorter half-lives than the corresponding theoretical predictions, are presented. The influence of the short half-lives on the r-process calculations of nuclear abundances is discussed. It is concluded that a significantly higher neutron density than the one obtained from explosive helium burning in supernovae is need to reproduce the observe abundances around A =80.