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DOE OSTI · 1855755

Multi-messenger heavy-ion collision physics

Gale, Charles·Paquet, Jean-François·Schenke, Björn·Shen, Chun
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Abstract

We report that this work studies the production of direct photons in relativistic nuclear collisions, along with the production of hadrons. Radiation from the very first instants to the final moments of the evolution is included. The hybrid model used here describes all stages of relativistic heavy-ion collisions. Chronologically, those are an initial state reflecting the collision of nuclei described within the Color Glass Condensate effective theory; a pre-equilibrium phase based on non-equilibrium linear response; relativistic viscous hydrodynamics, and a hadronic afterburner. The effect of the preequilibrium phase on both photonic and hadronic observables is highlighted for the first time. The potential of photon observables - spectrum, differential elliptic and triangular flow - to reveal the chemical equilibration time is studied. Finally, we consider "small collision systems", including proton+nucleus collisions and collisions of light nuclei, as probed by hadronic and electromagnetic observables. We demonstrate how photon production can signal the formation of quark-gluon plasma in such small systems.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSlepton productionparticle productionphoton productionquark productionrelativistic heavy-ion collisionsresonance production

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Gale, Charles, Paquet, Jean-François, Schenke, Björn, Shen, Chun. 2022-01-14. Multi-messenger heavy-ion collision physics. https://doi.org/10.1103/physrevc.105.014909

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