Collective flow phenomena of protons and π- mesons in nucleus-nucleus collisions at a momentum of 4.2 - 4.5 GeV/c per nucleon

The collective properties of protons and π- mesons in He-C, C-C, C-Ne, C-Cu and C-Ta collisions at a momentum of 4.2 - 4.5 GeV/c per nucleon (E = 3.4 - 3.7 GeV/nucleon) have been investigated. The data is obtained by SKM-200-GIBS and 2-m Propane Bubble Chamber of JINR. The directed (in-plane) protons and π- mesons have been observed in the above-mentioned interactions. In He-C, C-C and C-Ne interactions the directed flow of π- mesons is in the same direction as for protons, while in C-Cu and C-Ta collisions pions show antiflow behaviour. The absolute value of flow increases linearly with the increase of AP, AT, from 95 MeV for He-C up to 178 MeV for C-Ta for protons and from 17 MeV for He-C up to -74(module) MeV for C-Ta for π mesons. The Quark-Gluon String Model reproduces quite well the experimental results