On the Possibility of Event Shape Selection in Relativistic Heavy Ion Collisions

Abstract

We investigate the possibility of selecting heavy ion collision events with certain features in the initial state ("event engineering"). Anisotropic flow measurements in heavy ion reactions have confirmed the almost ideal fluid dynamical behaviour of the hot and dense quark gluon plasma state. As a consequence, it is intriguing to pursue the idea of selecting collisions with a certain special initial geometry, e.g., a large ellipsoidal or triangular deformation, by classifying events by the value of their final observed flow coefficients. This procedure could be especially interesting for azimuthally dependent jet energy loss studies. We investigate the correlation between initial state features and final state momentum space anisotropies within an event-by-event hybrid approach. We find that the finite particle number and hadronic rescattering of the final state leads to large event-by-event fluctuations in the observables that could be used to characterize the features of the initial state. This makes event engineering by final state selection difficult.

5 pages, 8 figures, minor changes as published in PRC

References in corpus (8)

• PYTHIA 6.4 Physics and Manual
• Elliptic and triangular flow in event-by-event (3+1)D viscous hydrodynamics
• Triangularity and Dipole Asymmetry in Heavy Ion Collisions
• Fully integrated transport approach to heavy ion reactions with an intermediate hydrodynamic stage
• Triangular flow in event-by-event ideal hydrodynamics in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=200A$ GeV
• Constraining the initial state granularity with bulk observables in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=200$ GeV
• $<m_T>$ excitation function: Freeze-out and equation of state dependence
• Initial state fluctuations and final state correlations: Status and open questions

Cited by in corpus (10)

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• Properties of the QCD Matter -- An Experimental Review of Selected Results from RHIC BES Program
• Transverse momentum-flow correlations in relativistic heavy-ion collisions
• Anisotropic flow in transport+hydrodynamics hybrid approaches
• Hydrodynamic flow amplitude correlations in event-by-event fluctuating heavy-ion collisions
• Elucidating the event-by-event flow fluctuations in heavy-ion collisions via the event shape selection technique
• Characterization of initial fluctuations for the hydrodynamical description of heavy ion collisions
• Anisotropic flow fluctuations in hydro-inspired freeze-out model for relativistic heavy ion collisions
• Collective Flow of QCD Matter: a Historical Introduction
• Search for the chiral magnetic effect through beam energy dependence of charge separation using event shape selection