Nuclear transparency effect in proton and deuteron induced interaction with carbon nuclei

Abstract

We used the nuclear transparency effect of π+-mesons in proton and deuteron induced interactions with carbon nuclei at 4.2 A GeV/c for studying the properties of nuclear matter. The average values of multiplicity, momentum and transverse momentum of the π+-mesons are analyzed as a function of the number of identified protons in an event. We used the value of pseudorapidity (η1/2) corresponding to Half angle (θ1/2) to see the effect of nuclear transparency for the π+meson in the nuclear medium. The η1/2 divides the multiplicity of charged particles into two equal parts in nucleon-nucleon interaction at 4.2 A GeV/c. We observed several cases where the behavior could be considered as transparency effect. For quantitative description, the results are compared with cascade model. Some simple calculation using Collective Tube Model (CTM) support the idea of collective interaction with grouped nucleon encountered when propagating through the target nucleus.