The cross sections for the nuclear reactions O16(p,pn)O15 and O16(p,pna)C11.

Absolute cross sections have been measured for the reactions O16(p,pn)O15 and O16(p,pna)C11 over the proton energy range 18 to 85 Mev. The proton beam intensity was monitored by the C12(p,pn)C11 reaction and as secondary monitor by the Cu63(p,n) and (p,pn) reactions. The oxygen target material was quartz. The curve of O16(p,pn)O15 shows a broad maximum of about 90 mb from 30 to 45 Mev, followed by a slow decrease. The shape of the curve is very similar to the one for the C12(p,pn)C11 reaction. The yield curve of O16(p,pna)C11 increases slowly from the threshold at 27.5 Mev up to 48 Mev, where the maximum value is 25 mb. From that value it decreases to 20mb at 85 Mev