Precise measurement of energies inSn115following the(n,γ)reaction

Abstract

The first measurement of $\ensuremath{\gamma}$ rays from the $^{114}\mathrm{Sn}(n,\ensuremath{\gamma})$ reaction using cold neutrons, performed with an array of Ge detectors at the PF1B facility of the Institute Laue-Langevin in Grenoble, has provided the most accurate energy, ${Q}_{\ensuremath{\beta}}=173(12)$ eV, of ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of the $^{115}\mathrm{In}$ ground state to the first excited state in $^{115}\mathrm{Sn}$. This is the lowest of all such energies in the known nuclear landscape. The accuracy of the neutron binding energy of $^{115}\mathrm{Sn}$ and the mass of $^{114}\mathrm{Sn}$ have been improved.