C12(π−, π−n)C11Excitation Function

The ${\mathrm{C}}^{12}({\pi }^{-}, {\pi }^{-}n){\mathrm{C}}^{11}$ excitation function was measured with incident pions of energies from 0.45 to 1.9 GeV. The present work supplements the lower energy measurements of Reeder and Markowitz. The excitation function of this simple nuclear reaction shows effects of the elementary pion-nucleon resonances. The ${\pi }^{-}-n$ resonances tend to be reproduced in the excitation function, while the ${\pi }^{-}-p$ resonances tend to cause a reduction in the cross sections. The production of ${\mathrm{C}}^{11}$ and ${\mathrm{F}}^{18}$ by ${\pi }^{-}$ interactions with Al targets was also studied over the same energy range. These excitation functions do not exhibit any structure.