MicroscopicBa130(n, γ)Cross Section and the Origin ofXe131on the Moon

The ${}_{}{}^{130}{}_{}{}^{}\mathrm{Ba}(n, \gamma )$ cross section has been measured from 0.5 to 5000 eV with an energy resolution of 0.4%. The large epithermal resonances found in this experiment explain the anomalously high concentrations of ${}_{}{}^{131}{}_{}{}^{}\mathrm{Xe}$ found in lunar rocks, and the measured resonance parameters provide one with a quantitative tool for correlating burial depth with exposure age for lunar samples.