Spectroscopy of neutron rich microsecond isomers near the doubly magic 132Sn

Abstract

Experiments have been conducted at the LOHENGRIN spectrometer at the ILL high flux reactor (Grenoble) in order to search for μs isomers in the neutron rich region in the vicinity of 50 132 Sn82. The details of the experimental set-up are given in [1,2]. The nuclei were produced by thermal neutron induced fission of 235U and 239,241Pu. The LOHENGRIN spectrometer was used to separate the fission fragments (FF) recoiling from a thin target of about 400 μg/cm2, according to their A/q ratios. The detection is based on the time correlation between the FF and the γ rays or the conversion electrons from isomer.