Neutron capture cross section of ¹⁸⁵Re leading to ground and isomer states of ¹⁸⁶Re in the keV-neutron energy region

Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan

^* e-mail: buchi@lane.iir.titech.ac.jp

Published online: 16 May 2018

Abstract

The neutron capture cross section of ¹⁸⁵Re was measured in the astrophysically important energy region. Measurements were made using a neutron beam from a ⁷Li(p,n)⁷Be neutron source with energies ranging from 3 to 90 keV. Two different experimental techniques, time-of-flight (TOF) and activation methods, were employed. In the TOF experiments, the total neutron capture cross section of ¹⁸⁵Re was determined by the pulse-height weighting technique. In the activation method, the partial capture cross section leading to the ground state of ¹⁸⁶Re was measured by detecting decay γ-rays from neutron activated samples. The present cross section values were compared with evaluated cross section data and previous measurements. The difference between the TOF and activation results was smaller than experimental uncertainties. This suggests that the production cross section of isomer states of ¹⁸⁶Re is very small.