Cross Section forC12(p, pn)C11

Abstract

The cross section for the reaction ${\mathrm{C}}^{12}(p, pn){\mathrm{C}}^{11}$ has been measured at a proton energy of 461 Mev; the result is $\sigma =31\mathrm{}$ mb with an associated error of 3 percent. Because of some disagreement among earlier experiments by several laboratories, a detailed discussion of the errors involved in those measurements is given, and in particular, a discussion of the techniques used for positron counting in a $4\pi$ proportional counter. A summary of the present state of knowledge of this reaction is presented.