A thin target of isotopic boron has been bombarded with 7.03-Mev protons. The neutrons from the ${\mathrm{B}}^{11}(p, n){\mathrm{C}}^{11}$ reaction, studied by means of nuclear emulsions, indicate an excited state of ${\mathrm{C}}^{11}$ at 2.01±0.06 Mev.

• Received 11 April 1956

DOI:https://doi.org/10.1103/PhysRev.103.356