The absolute cross section for the reaction $\mathrm{C}(\alpha , X){}_{}{}^{11}{}_{}{}^{}\mathrm{C}$ has been measured from 0.64 to 2.8 GeV using a counter telescope to determine the alpha flux and a plastic scintillator target to determine the ${}_{}{}^{11}{}_{}{}^{}\mathrm{C}$ activity. The results are 55.6±2.2 mb (0.64 GeV), 49.2±1.9 mb (1.2 GeV), 44.1±1.8 mb (2.0 GeV), and 42.0±1.7 mb (2.8 GeV).

NUCLEAR REACTIONS $\mathrm{C}(\alpha , X){}_{}{}^{11}{}_{}{}^{}\mathrm{C}$, $E=0.64\mathrm{}$, 1.2, 2.0, 2.8 GeV; measured absolute cross section.

• Received 1 September 1982

DOI:https://doi.org/10.1103/PhysRevC.26.2565