The differential cross sections for four highest energy proton groups from the ${\mathrm{Be}}^9({\mathrm{He}}^3, p){\mathrm{B}}^{11}$ reaction have been measured at a bombarding energy of 2.00 Mev over the angular region extending from 5° to 170°. In order to fit these data with Legendre polynomial expansions, it was necessary to include polynomials up to the sixth degree. The coefficients in these expansions are tabulated for each proton group. These results by themselves are not inconsistent with the compound nucleus model of nuclear reactions, but when viewed in connection with other results, they indicate the possibility that direct interactions may play an important part in ${\mathrm{He}}^3$-induced reactions.

• Received 13 August 1956

DOI:https://doi.org/10.1103/PhysRev.104.1446