Measurement of the 187Re(n,2n)186mRe Destruction Cross-section

We are continuing a program to measure cross sections for $^{187}$Re(n,2n$\gamma$) reactions with particular interest in confirming a transition that has tentatively been identified as a doorway transition feeding the $^{186}$Re E$_x$=149(7)~keV isomeric state. The cross sections are being measured using pulsed, nearly mono-energetic neutron beams, as well as an array of planar HPGe $\gamma$-ray detectors. At present, the reaction cross sections for $^{187}$Re(n,2n$\gamma$) are poorly known, so measuring the cross sections have positive implications, for example, on reactor physics since Re is a common fission fragment. Furthermore, refining the cross section measurements may reduce uncertainties in the Re/Os cosmochronometer. Funding provided by NSF grant NSF-PHY-08-51813.