Multiplicity in proton-nucleus interactions at 200 GeV/ c

Abstract

Experimental results on multiparticle production in proton-nucleus collisions based on an exposure of emulsion stack to 200 GeV/ c proton beam at NAL are presented. It is found that the average charged particle multiplicity 〈n s 〉 = 13.0 ± 0.4, D ≡ (〈n s 2〉 − 〈n s 〉 2) 1 2 = 8.5 ± 0.4 and 〈N h 〉 = 7.3 ± 0.2 . Energy dependence of R em = 〈 n s〉/〈 n ch〉, where 〈 n ch〉 is the charged particle multiplicity in pp collisions, is investigated in the range 7.1–8000 GeV/ c. R em attains a constant value of 1.71 ± 0.04 beyond 200 GeV/ c and furthermore this value of R em implies an A dependence R A = A 0.13. It is found that even for p-nucleus collisions D increases linearly with 〈 n s〉 with about the same slope as for pp collisions.