Directed, elliptic and triangular flow of protons in Au+Au reactions at 1.23 AGeV: A theoretical analysis of the recent HADES data

Abstract

Recently, the HADES experiment at GSI has provided preliminary data on the directed flow, $v_1$ elliptic flow, $v_2$ and triangular flow, $v_3$ of protons in Au+Au reactions at a beam energy of 1.23 A GeV. Here we present a theoretical discussion of these flow harmonics within the UrQMD transport approach. We show that all flow harmonics, including the triangular flow, provide a consistent picture of the expansion of the system, if potential interactions are taken into account. Investigating the dependence of the flow harmonics on the nuclear interaction potentials it is shown that especially $v_3$ can serve as a sensitive probe for the nuclear equation of state at such low energies. The triangular flow and its excitation function with respect to the reaction-plane were calculated for the first time and indicate a complex interplay of the time-evolution of the system and the initial conditions at low beam-energies. Our study also indicates a significant softening of the equation of state at beam energies above $E_{\mathrm{lab}}>7$A GeV which can be explored by at the future FAIR facility.

7 pages, 10 figures, accepted version for publication

References in corpus (11)

• Triangularity and Dipole Asymmetry in Heavy Ion Collisions
• Triangular flow in event-by-event ideal hydrodynamics in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=200A$ GeV
• Inclusive charged hadron elliptic flow in Au + Au collisions at $\sqrt{s_{NN}}$ = 7.7 - 39 GeV
• Elliptic Flow: A Brief Review
• Directed and elliptic flow in heavy ion collisions from $E_{\mathrm{beam}}=90$ MeV/nucleon to $E_{c.m.}=200$ GeV/nucleon
• Directed Flow Indicates a Crossover Deconfinement Transition in Relativistic Nuclear Collisions
• Equation of state dependence of directed flow in a microscopic transport model
• The effect of "pre-formed" hadron potentials on the dynamics of heavy ion collisions and the HBT puzzle
• Deep sub-threshold $\Xi$ and $\Lambda$ production in nuclear collisions with the UrQMD transport model
• Enhancement of elliptic flow can signal a first order phase transition in high energy heavy ion collisions
• Effect of initial fluctuations on the collective flow in intermediate-energy heavy ion collisions

Cited by in corpus (24)

• Mapping the Phases of Quantum Chromodynamics with Beam Energy Scan
• Directed, elliptic and higher order flow harmonics of protons, deuterons and tritons in Au+Au collisions at $\sqrt{s_{NN}}=2.4$ GeV
• Momentum-dependent potential and collective flows within the relativistic quantum molecular dynamics approach based on relativistic mean-field theory
• First, second, third and fourth flow harmonics of deuterons and protons in Au+Au reactions at 1.23 A GeV
• Sensitivity of the excitation functions of collective flow to relativistic scalar and vector meson interactions in the relativistic quantum molecular dynamics model RQMD.RMF
• Effects of a phase transition on two-pion interferometry in heavy-ion collisions at $\sqrt{s_{\mathrm{NN}}}=2.4-7.7$ GeV
• Directed flow of $\Lambda$ in high-energy heavy-ion collisions and $\Lambda$ potential in dense nuclear matter
• Collective flow and correlations measurements with HADES in Au+Au collisions at 1.23 AGeV
• A first estimate of $\eta /s$ in Au+Au reactions at E${}_{\mathrm{lab}}=1.23$ $A$GeV
• Dilepton Signature of a First-Order Phase Transition
• Ambiguities in the hadro-chemical freeze-out of Au+Au collisions at SIS18 energies and how to resolve them
• Delta mass shift as a thermometer of kinetic decoupling in Au+Au reactions at 1.23 AGeV
• Understanding the energy dependence of $B_2$ in heavy ion collisions: Interplay of volume and space-momentum correlations
• Decoding the flow evolution in Au+Au reactions at $1.23A$ GeV using hadron flow correlations and dileptons
• $\Delta$ resonances in Ca+Ca, Ni+Ni and Au+Au reactions from 1 AGeV to 2 AGeV: Consistency between yields, mass shifts and decoupling temperatures
• Effects of the QCD phase transition on hadronic observables in relativistic hydrodynamic simulations of heavy-ion reactions in the FAIR/NICA energy regime
• Nuclear interactions and net-proton number fluctuations in heavy ion collisions at the SIS18 accelerator
• Reaction plane correlated triangular flow in Au+Au collisions at $\sqrt{s_{NN}}=3$ GeV
• Density Functional Equation of State and Its Application to the Phenomenology of Heavy-Ion Collisions
• Probing the Three-dimension Emission Source and Neutron Skin via $\pi$-$\pi$ Correlations in Heavy-Ion Collisions
• Probing system size dependence at high baryon density by systematic comparison of Ag+Ag and Au+Au reactions at 1.23$A$ GeV
• Harmonic flow correlations in Au+Au reactions at 1.23 AGeV: A new testing ground for the Equation-of-State and expansion geometry
• Unlocking the initial neutron density distribution from the two-pion HBT correlation function in heavy-ion collisions
• Toward a Unified Understanding of the Dense Matter Equation of State