π−-Nucleon Collisions at 1.5 Bev

Abstract

The results of an extensive search for the interactions of 1.5-Bev ${\pi }^{-}$ mesons with nucleons in nuclear emulsion are given. By comparing the cross section for ${\pi }^{-}-P$ interactions in emulsion to the cross sections as measured by counters, it is deduced that half the "${\pi }^{-}-P$" collisions are collision of ${\pi }^{-}$ with protons on the edge of a nucleus. Arguments are presented to indicate that the basic features of the ${\pi }^{-}-P$ interactions are not seriously disguised by the struck nucleons being in a nucleus.