Total Cross Section of Be, O, Na, and Ca for Fast Neutrons

Abstract

The total cross sections of Be, O, Na, and Ca were investigated as a function of neutron energy in ranges between 30 and 1000 kev with a resolving power of approximately 20 kev. In Be a resonance was observed at 625 kev, presumably caused by $p$-neutrons. The resonance in O at 440 kev is probably due to $p$-neutrons forming a compound nucleus of spin $\frac{3}{2}$. In Na and Ca numerous peaks were found. The cross section of Ca has values below 1.5 barns over a considerable range of energies.