Lifetime measurements in sd-shell nuclei : (II). Mean lives of 33S levels

Abstract

Levels in 33S were populated with the 32S(d, p)33S reaction at Ed = 5.00 MeV. Gamma rays were simultaneously measured in coincidence with protons at angles θp = 45° and −45° or 135° and −135°. From the coincidence Doppler shift attenuation measurements mean lives of τm = 1730−450+1100, 150 ± 45, 140 ± 30, 13 ± 5, >7000, 86 ± 25 and 28 ± 9 fs were found for the 33S levels at Ex = 0.84, 1.97, 2.31, 2.87, 2.94, 2.97 and 3.22 MeV, respectively.

Calculations with MSDI shell-model wave functions and a fit of single-particle reduced matrix elements to experimentally known mean lives of neighbouring nuclei, predict very well the measured mean lives, known branchings and mixing parameters.