Thermal neutron capture cross sections of zirconium-91 and zirconium-93 by prompt γ-ray spectroscopy

A lower limit of 0.63 +/- 0.02 b has been determined for the thermal neutron capture cross section (sigma(0)) of Zr-93 from a measurement of the prompt gamma-rays emitted by the Zr-93 (n(th),gamma)Zr-94 reaction. The present result for Zr-93 is much smaller than the single previously reported measurement as well as compiled and evaluated values for this cross section. This work also reports a lower limit for sigma(0) of Zr-91 as 1.30 +/- 0.04 b, which is consistent with the single previously reported measurement, as well as compiled and evaluated values for this cross section, within the quoted uncertainties.