Prompt photon yield and $v_2$ coefficient from gluon fusion induced by magnetic field in heavy-ion collision

Abstract

We compute the production of prompt photons and the $v_2$ harmonic coefficient in relativistic heavy-ion collisions induced by gluon fusion in the presence of an intense magnetic field, during the early stages of the reaction. The calculations take into account several parameters which are relevant to the description of the experimental transverse momentum distribution, and elliptic flow for RHIC and LHC energies. The main imput is the strength of the magnetic field which varies in magnitude from 1 to 3 times the pion mass squared, and allows the gluon fusion that otherwise is forbidden in the absence of the field. The high gluon occupation number and the value of the saturation scale also play an important role in our calculation, as well as a flow velocity and geometrical factors. Our results support the idea that the origin of at least some of the photon excess observed in heavy-ion experiments may arise from magnetic field induced processes, and gives a good description of the experimental data.

arXiv comment6 pages, 2 figures, conference paper from ISMD 2017

References in corpus (16)

• The effects of topological charge change in heavy ion collisions: "Event by event P and CP violation"
• Event-by-event fluctuations of magnetic and electric fields in heavy ion collisions
• Some Features of the Glasma
• The production of photons in relativistic heavy-ion collisions
• Coherent gluon production in very high energy heavy ion collisions
• Direct photon production in Pb-Pb collisions at $\sqrt{s_\rm{NN}}$ = 2.76 TeV
• Azimuthally anisotropic emission of low-momentum direct photons in Au$+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV
• Pseudo-Critical Enhancement of Thermal Photons in Relativistic Heavy-Ion Collisions
• Hadronic and partonic sources of direct photons in relativistic heavy-ion collisions
• The Glasma, Photons and the Implications of Anisotropy
• Parametric estimate of the relative photon yields from the Glasma and the Quark-Gluon Plasma in heavy-ion collisions
• On the role of magnetic field in photon excess in heavy ion collisions
• Prompt photon yield and elliptic flow from gluon fusion induced by magnetic fields in relativistic heavy-ion collisions
• Effect of magnetic field on the photon radiation from quark-gluon plasma in heavy ion collisions
• A Tale of Tails: Photon Rates and Flow in Ultra-Relativistic Heavy Ion Collisions
• Thermal photon production from gluon fusion induced by magnetic fields in relativistic heavy-ion collisions