Proton Induced Coherent Pion Production

The short range component of the nucleon‐nucleus interaction is phenomenologically described by effective interaction including the so‐called Landau‐Migdal parameters g′, among which only gΔΔ′ has been left unfixed because of the scarcity of experimental information. We propose Coherent Pion Production (CPP) measurement 12C(p, nπ+)12C(g.s.) to get quantitative information on gΔΔ′. A preliminary CPP experiment was performed at the RCNP neutron time of flight facility by involving exclusive measurement of pions and neutrons. We have specially developed for this purpose a new pion counter and embedded it in the beam swinger magnet of the neutron time of flight facility. We describe the experiment and preliminary result from the pion‐neutron coincidences.