CERN Accelerating science

Preprint
Report number	arXiv:2405.20210
Title	The unexpected uses of a bowling pin: anisotropic flow in fixed-target $^{208}$Pb+$^{20}$Ne collisions as a probe of quark-gluon plasma
Author(s)	Giacalone, Giuliano (U. Heidelberg, ITP) ; Zhao, Wenbin (LBNL, NSD ; UC, Berkeley) ; Bally, Benjamin (IRFU, Saclay) ; Shen, Shihang (IAS, Julich) ; Duguet, Thomas (IRFU, Saclay ; KU Leuven, Dept. Phys. Astron.) ; Ebran, Jean-Paul (CEA DAM ; U. Paris-Saclay) ; Elhatisari, Serdar (Gaziantep U.) ; Frosini, Mikael (CEA Cadarache) ; Lähde, Timo A. (Julich, Forschungszentrum ; IAS, Julich ; JCHP, Julich ; JARA, Aachen) ; Lee, Dean (Michigan State U.) ; Lu, Bing-Nan (GSCAEP, Beijing) ; Ma, Yuan-Zhuo (Michigan State U.) ; Meißner, Ulf-G. (IAS, Julich ; Bonn U., HISKP ; U. Bonn, Phys. Inst., BCTP) ; Nijs, Govert (CERN) ; Noronha-Hostler, Jacquelyn (Illinois U., Urbana) ; Plumberg, Christopher (Pepperdine U.) ; Rodríguez, Tomás R. (Madrid U.) ; Roth, Robert (Darmstadt, Tech. U. ; FAIR, Darmstadt) ; van der Schee, Wilke (CERN ; Utrecht U. ; Nikhef, Amsterdam) ; Schenke, Björn (Brookhaven Natl. Lab.) ; Shen, Chun (Wayne State U. ; RIKEN BNL) ; Somà, Vittorio (IRFU, Saclay)
Imprint	2024-05-30
Number of pages	12
Subject category	nucl-ex ; Nuclear Physics - Experiment ; hep-ph ; Particle Physics - Phenomenology ; nucl-th ; Nuclear Physics - Theory
Abstract	The System for Measuring Overlap with Gas (SMOG2) at the LHCb detector enables the study of fixed-target ion-ion collisions at relativistic energies ($\sqrt{s_{\rm NN}}\sim100$ GeV in the centre-of-mass). With input from \textit{ab initio} calculations of the structure of $^{16}$O and $^{20}$Ne, we compute 3+1D hydrodynamic predictions for the anisotropic flow of Pb+Ne and Pb+O collisions, to be tested with upcoming LHCb data. This will allow the detailed study of quark-gluon plasma (QGP) formation as well as experimental tests of the predicted nuclear shapes. Elliptic flow ($v_2$) in Pb+Ne collisions is greatly enhanced compared to the Pb+O baseline due to the shape of $^{20}$Ne, which is deformed in a bowling-pin geometry. Owing to the large $^{208}$Pb radius, this effect is seen in a broad centrality range, a unique feature of this collision configuration. Larger elliptic flow further enhances the quadrangular flow ($v_4$) of Pb+Ne collisions via non-linear coupling, and impacts the sign of the kurtosis of the elliptic flow vector distribution ($c_2{4}$). Exploiting the shape of $^{20}$Ne proves thus an ideal method to investigate the formation of QGP in fixed-target experiments at LHCb, and demonstrates the power of SMOG2 as a tool to image nuclear ground states.
Other source	Inspire
Copyright/License	preprint: (License: CC BY 4.0)