Search for Delayed-Neutron Emission inBr86Decay

A search for delayed-neutron activity in the decay of 54-sec ${\mathrm{Br}}^{86}$ was carried out. No statistically significant activity was observed, but an upper limit for the neutron branch of ∼0.25% was set. This limit corresponds to a maximum of ∼10% for the possible contribution of ${\mathrm{Br}}^{86}$ to the 55-sec delayed-neutron period observed in the thermal neutron fission of ${\mathrm{U}}^{235}$ and ascribed to ${\mathrm{Br}}^{87}$.