PACIAE 2.1: An updated issue of the parton and hadron cascade model PACIAE 2.0

TL;DR

The paper updates the PACIAE 2.0 model for relativistic nuclear collisions to version 2.1, introducing an elliptical transverse momentum distribution to better study anisotropy in final hadronic states.

Contribution

It introduces a new elliptical transverse momentum distribution in PACIAE 2.1 to improve the analysis of transverse momentum anisotropy in nuclear collision simulations.

Findings

Enhanced modeling of transverse momentum anisotropy.

Better agreement with experimental data on hadronic states.

Improved simulation accuracy for relativistic nuclear collisions.

Abstract

We have updated the parton and hadron cascade model PACIAE 2.0 for relativistic nuclear collisions (cf. Comput. Phys. Comm. 183(2012)333) to the new issue of PACIAE 2.1. The PACIAE model is based on PYTHIA. In the PYTHIA model, once the generated particle/parton transverse momentum $p_T$ is randomly selected, its component of $[p_x,p_y]$ was originally put on the circle with radius $p_T$ randomly. It is now replaced by put on the circumference of ellipse with half major and minor axes of $p_T(1+\delta_p)$ and $p_T(1-\delta_p)$, respectively, in order to investigate better the transverse momentum anisotropy in final hadronic state.