(p, π+) reaction on1pshell nuclei atEp=200MeV

Energy spectra of pions produced by the ($p, {\pi }^{+}$) reaction on ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$, ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, and ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ leading to discrete final states have been measured with 170-210 keV resolution. Except for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, final states that can be reached by the simple transfer of a neutron tend to be favored compared to final states of more complicated structure, which is suggestive of a one-step reaction mechanism. These ($p, {\pi }^{+}$) spectra are surprisingly similar to ($d, p$) spectra at much lower momentum transfer. For ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, single-particle and 2p-1h final states are populated about equally and there is little similarity between the ($p, {\pi }^{+}$) and ($d, p$) spectra.