COHERENT PION-PRODUCTION IN THE (HE-3,T) REACTION IN NUCLEI

We have evaluated the cross section for coherent pion production in th e He-3 + C-12 --> t + C-12 + pi+ reaction. The DELTA peak of the energ y distribution is considerably shifted with respect to the peak in the p (He-3, t)DELTA++ reaction. The coherent pions represent a sizable f raction of all pions produced and are a major ingredient in the interp retation of the shift of the DELTA peak in the inclusive (He-3, t) rea ction in nuclei. The coherent production process qualifies as producti on of virtual pions followed by elastic scattering of the virtual pion s with the nucleus and the investigation of this channel will offer in formation about pion nucleus interaction complementary to the one obta ined from scattering of real pions.