Results from SKM-200-GIBS on multiparticle azimuthal correlations in C-Ne and C-Cu collisions at energy of 3.7 GeV per nucleon

Abstract

The transverse momentum technique is used to analyse charged-particle exclusive data in central C-Ne and C-Cu interactions at energy of 3.7 GeV per nucleon. Clear evidence of in-plane and out-of-plane (squeeze-out) flow effects for protons and pi^{-} mesons have been obtained. In C-Ne interactions in-plane flow of pi^{-} mesons is in the same direction as for the protons, while in C-Cu collisions pions show antuflow behaviour. From the transverse momentum and azimuthal distributions of protons and pi^{-} mesons with respect to the reaction plane, the flow (the measure of the amount of collective transverse momentum transfer in the reaction plane) and the parameter a_{2} (the measure of the anisotropic emission strength) have been extracted. The flow effects increase with the mass of the particle and the mass number of target A_{T}. The comparison of our in-plane flow results with flow data for various projectile/target configurations was made using the scaled flow F_{S}=F/(A_{P} ^{1/3}+A_{T}^{1/3}). F_{S} demonstrates a common scaling behaviour for flow values from different systems. The Quark Gluon String Model (QGSM) was used for the comparison with the experimental data. The QGSM yields a signature of in-plane and out-of-plane flow effects in C-ne and C-Cu collisions for protons.