Negative pions were stopped in LiN${\mathrm{H}}_2$ and the nuclear deexcitation $\gamma$ rays were observed. The Dopplerbroadened line shape of the decay $\gamma$ rays from the $2^{+}$ state of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ at 4439 keV was analyzed to obtain the momentum distribution of the recoiling ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ nuclei. This distribution is compared with the prediction of a simple model which assumes one-step quasifree ${\pi }^{-}$ absorption on a quasideuteron pair.

NUCLEAR REACTIONS ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}({\pi }^{-},X\gamma )$, $E=0\mathrm{}$; measured $E_{\gamma }$ and Doppler broadening.

• Received 1 October 1976

DOI:https://doi.org/10.1103/PhysRevC.15.984