Collective flows of protons and deuterons in Au + Au collisions at $E_{beam}$ = 1.23$A$ GeV by the IQMD model

TL;DR

This study uses the IQMD model to simulate collective flows of protons and deuterons in Au+Au collisions at 1.23A GeV, comparing coalescence models and analyzing flow coefficients and correlations.

Contribution

It introduces a detailed comparison of coalescence models and analyzes flow coefficients and correlations in heavy-ion collisions at intermediate energies.

Findings

Reasonable match of proton and deuteron spectra to experimental data.

Observation of constituent nucleon scaling in flow ratios.

Analysis of flow correlations and centrality dependence.

Abstract

Collective flows of protons and deuterons for Au + Au collisions at beam energy $E_{beam}$ = 1.23 $A$ GeV were simulated by an Isospin dependent Quantum Molecular Dynamics (IQMD) model. Two coalescence models, namely naive coalescence and dynamical coalescence models, for the formation of deuterons are compared. After reasonable match of rapidity spectra of protons and deuterons to the High Acceptance DiElectron Spectrometer (HADES) data is reached, we apply an event-plane method to calculate the first four-order collective flow coefficients as well as the ratios of $<v_4>/<v_2>^2$ and $<v_3>/<v_1><v_2>$, and observe the number of constituent nucleon scaling among protons and deuterons. In addition, the dependence of $\epsilon_n$ and $v_n$ as well as the ratio $<v_n>$/$\epsilon_n$ on the centrality is obtained. Lastly, we further investigate the Pearson coefficients $corr(v_n,v_m)$ between the first four harmonic flows for protons and deuterons as a function of rapidity and centrality.