Measurements of proton total reaction cross sections for ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ have been made in the energy range between 20-44 MeV. The cross sections show irregular energy variation for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ at about 23.8 and 25.9 MeV, and for ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ at 30.3 and 33.5 MeV; irregularities were not observed clearly for ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$ or ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$.

NUCLEAR REACTIONS ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$: $20 \mathrm{MeV}<T<\mathrm{}44\mathrm{} \mathrm{MeV}$, between 23 and 51 measurements for each nucleus; measured ${\sigma }_R$; natural targets, except for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ gas and Si${\mathrm{O}}_2$ used for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ measurements.

• Received 27 May 1975

DOI:https://doi.org/10.1103/PhysRevC.12.1093