First measurement of beta decay half-lives in neutron-rich Tl and Bi isotopes

Abstract: Neutron-rich isotopes around lead, beyond , have been studied exploiting the fragmentation of an uranium primary beam at the FRS-RISING setup at GSI. For the first time β-decay half-lives of and isotopes have been derived. The half-lives have been extracted using a numerical simulation developed for experiments in high-background conditions. Comparison with state of the art models used in r-process calculations is given, showing a systematic underestimation of the experimental values, at variance from close-lying nuclei. [Copyright &y& Elsevier]