Shining a Light on the QGP - Electroweak Probes Experimental Summary

Abstract

Objects which are only subject to the electroweak force are an ideal probe of QCD in high density and temperature environments as they carry information about the conditions during their production out of the QGP without interacting with it. Thus they can be used to characterize the initial state as well as several properties of the QGP and its evolution. Within this article the recent results regarding these electroweak probes presented at the 9 th Hard Probes Conference (Aix-les-Bains, France, 2018) will be summarized. In particular the following questions will be addressed: Can we determine the necessary energy and particle density for the QGP creation using electromagnetic probes? Can we use light-by-light scattering in heavy-ion collisions to do precision tests of QED and measure the magnetic field of the QGP? How are quark jets modified by the presence of the QGP? What can we learn about the initial state and scaling properties in pp, p(d)-A and A-A collisions from the production of high p T photons, Z 0 and W ± bosons? In the version provided on arXiv, additional plots are included in the appendix with respect to the version submitted for publication in the journal. Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). https://pos.sissa.it/ ALICE (0-20% Pb-Pb 2.76TeV) ALICE (20-40% Pb-Pb 2.76TeV) ALICE (40-80% Pb-Pb 2.76TeV) CMS (0-10% Pb-Pb 2.76TeV) CMS (10-30% Pb-Pb 2.76TeV) CMS (30-100% Pb-Pb 2.76TeV) PHENIX (0-20% Au-Au 0.2TeV) PHENIX (20-40% Au-Au 0.2TeV) PHENIX (40-60% Au-Au 0.2TeV) PHENIX (60-92% Au-Au 0.2TeV) PHENIX (0-92% Au-Au 0.2TeV) STAR (0-20% Au-Au 0.2TeV) STAR (20-40% Au-Au 0.2TeV) STAR (40-60% Au-Au 0.2TeV) STAR (60-80% Au-Au 0.2TeV) STAR (0-80% Au-Au 0.2TeV) PHENIX (0-40% Cu-Cu 0.2TeV) PHENIX (0-92% Cu-Cu 0.2TeV) PHENIX (0-20% Au-Au 62.4GeV) PHENIX (20-40% Au-Au 62.4GeV) PHENIX (0-86% Au-Au 62.4GeV) PHENIX (0-86% Au-Au 39GeV) WA98 (0-10% Pb-Pb 17.2GeV)