Evidence for the Statistical Model Obtained from (p, n) Spectra of the Odd-Even Elements V, Mn, Co, Nb, Rh, and In

Abstract

Spectra of neutrons emitted from ($p, n$) reactions have been measured for the essentially monoisotopic odd-even elements V, Mn, Co, Nb, Rh, and In. The 7-8 Mev protons used were obtained from the Livermore 90-in. cyclotron. Neutron energy distributions were determined using time-of-flight techniques. Experimental results indicate agreement with the compound statistical model of the nucleus. Relative level densities obtained in this manner were found to increase with atomic weight as theoretically expected. Assuming a level density of the form $\exp \left[2\mathrm{}{\left(a\epsilon \right)}^{\frac{1}{2}}\right]$, $a$ values were obtained which varied as $a=\frac{A}{13}$.