Study of collective matter flow in central C-Ne and C-Cu collisions at energy of 3.7 GeV per nucleon

TL;DR

This study investigates collective flow phenomena in central C-Ne and C-Cu collisions at 3.7 GeV per nucleon, revealing in-plane and out-of-plane flow effects, particle dependence, and a universal scaling behavior across different systems.

Contribution

It provides the first detailed analysis of flow effects in C-Ne and C-Cu collisions at this energy, demonstrating particle-dependent flow directions and a universal scaled flow behavior.

Findings

Protons and pions exhibit in-plane and out-of-plane flow effects.

Pions show in-plane flow in C-Ne and antiflow in C-Cu interactions.

Flow effects scale with particle mass and target atomic number.

Abstract

The transverse momentum technique is used to analyse charged-particle exclusive data in the central C-Ne and C-Cu interactions at energy of 3.7 Gev per nucleon. The 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 the $\pi^{-}$ mesons in-plane flow is in the same direction to the protons, while in C-Cu collisions pions show antiflow behaviour. From the transverse momentum and azimuthal distributions of protons and pi^{-} mesons with respect to the reaction plane the flow F (the measure of the amount of collective transverse momentum transfer in the reaction plane) and the parameter a_{2} (the measure of the strength of the anisotropic emission) have been extracted. The flow effects increase with the mass of the particle and atomic number of target A_{T}. The comparison of our in-plane flow results with flow data of various projectile/target configurations had been done by a scaled flow F_{S}=F/(A_{P}^{1/3}+A_{T}^{1/3}). F_{S} demonstrates a common scaling behaviour among flow values from different systems.