First, second, third and fourth flow harmonics of deuterons and protons in Au+Au reactions at 1.23 AGeV. (11th March 2020)

• Record Type: Journal Article
• Authors: Hillmann, Paula; Steinheimer, Jan; Reichert, Tom; Gaebel, Vincent; Bleicher, Marcus; Sombun, Sukanya; Herold, Christoph; Limphirat, Ayut
• Is Part Of: Journal of physics. Volume 47:Number 5(2020:May)
• Publication Date: 2020-03-11
• Subjects: collective flow -- deuterons -- protons -- HADES -- kinetic freeze-out -- coalescence -- equation of state; Nuclear physics -- Periodicals; Particles (Nuclear physics) -- Periodicals; Physique nucléaire -- Périodiques; Particules (Physique nucléaire) -- Périodiques; Kernfysica; Elementaire deeltjes; 539.7
• DOI: 10.1088/1361-6471/ab6fcf
• Languages: English
• ISSNs: 0954-3899

Abstract

Abstract: We explore the directed, elliptic, triangular and quadrangular flow of deuterons in Au+Au reactions at a beam energy of 1.23 AGeV within the UrQMD approach. These investigations are of direct relevance for the HADES experiment at GSI that has recently presented first data on the flow of light clusters in Au+Au collisions at 1.23 AGeV. To address the deuteron flow, UrQMD has been extended to include deuteron formation by coalescence. We find that this ansatz provides a very good description of the measured deuteron flow data, if a hard equation of state is used for the simulation. In addition we show that light cluster formation has a sizable impact on the proton flow and has to be taken into account to obtain reliable results in the forward/backward region. Based on the observed scaling of the flow, which is a natural result of coalescence, we conclude that deuteron production at GSI energies is a final state recombination effect. Finally, we also discuss the scaling relations of the higher order flow components up to v 4 . We show that v 3 ∼ v 1 v 2 and v 4 ∼ v 2 2 as function of transverse momentum and that the integrated v 2 2 ∼ v 4 over the investigated energy range from E lab = 0.1 AGeV to 40 AGeV.