Related papers: Photon production from gluon mediated quark-anti-q…
PHENIX has used the versatility of RHIC to map out low $p_{T}$ direct photon production as function of collision system size and beam energy. For systems with a size corresponding to a $dN_{ch}/d\eta$ larger than 20-30, we observe a large…
Results from the PHENIX experiment on direct-photon production in Au+Au collisions at sqrt{s_{NN}} = 200 GeV for transverse momenta 1 < p_T < 13 GeV/c are presented. Direct-photon yields at high p_T scale as expected for particle production…
The $p_T$ dependent elliptic and triangular flow parameters of direct photons are known to be dominated by thermal radiations. The non-thermal contributions dilute the photon anisotropic flow by adding extra weight factor in the $v_n$…
Results from the PHENIX experiment at RHIC on direct photon production in p+p, d+Au, and Au+Au collisions at sqrt(s_NN) = 200 GeV are presented. In p+p collisions, direct photon production at high p_T behaves as expected from perturbative…
We study the transverse momentum spectrum and the elliptic flow v2 of photons produced in Au+Au collisions at sqrt(s)=200 GeV using the Parton-Hadron-String Dynamics (PHSD) transport approach. As sources for photon production, we…
Direct photons are ideal tools to investigate kinematical and thermodynamical conditions of heavy ion collisions since they are emitted from all stages of the collision and once produced they leave the interaction region without further…
Direct photons are a powerful probe to study the properties of the unique matter created in ultrarelativistic heavy-ion collisions. They carry information on the various stages of a heavy-ion collision. At different transverse momenta (pT),…
In heavy-ion collisions, an excess in photon production, together with a larger than expected positive elliptic flow, has been observed, a phenomenon commonly referred to as the direct photon puzzle. In this work we study the mechanism of…
A major goal of experiments in heavy-ion physics is the characterization of the quark gluon plasma (QGP) produced in the collision of heavy ions at high energy. Direct photons are a particularly good probe of the produced medium because…
The PHENIX experiment discovered a large excess of low-$p_{T}$ direct photons in Au+Au collisions at 200 GeV compared to reference p+p collisions, which has been attributed to thermal radiation from the medium produced in the collisions. At…
When studying the initial state and evolution of the matter created in relativistic heavy ion collisions, high-pT direct photons are a powerful probe. They are created in initial hard processes and in parton fragmentation, and possibly in…
Prompt photons produced in a hard reaction are not accompanied with any final state interaction, either energy loss or absorption. Therefore, besides the Cronin enhancement at medium transverse momenta pT and small isotopic corrections at…
The photon production due to conversion of two gluons into a photon, $gg\rightarrow\gamma$, in the presence of the background gauge fields is studied within the specific mean-field approach to QCD vacuum. In this approach, mean field in the…
The thermal-photon emission from strongly coupled gauge theories at finite temperature is calculated by using holographic models for QCD in the Veneziano limit (V-QCD). These emission rates are then embedded in hydrodynamic simulations…
We investigate the production of direct photons in central Au-Au collisions at the relativistic Heavy-Ion Collider (RHIC) at 200 GeV per nucleon, considering all possible sources. We treat thermal photons emitted from a quark-gluon plasma…
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…
The PHENIX experiment at the Relativistic Heavy Ion Collider measured the second Fourier component $v_2$ of the direct-photon azimuthal anisotropy at midrapidity in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV. The results are presented…
The thermal-photon emission from strongly coupled gauge theories at finite temperature via the bottom-up models in holographic QCD in the deconfined phase is studied. The models are constructed to approximately reproduce the electric…
We present a detailed phenomenological study of direct photon production in association with a heavy-quark jet in pA collisions at the Relativistic Heavy Ion Collider (RHIC) and at the Large Hadron Collider (LHC) at next-to-leading order in…
Event-by-event fluctuations in the positions of nucleons in two colliding identical nuclei can lead to non-uniform initial energy density distribution on the transverse plane. In addition to initial state fluctuations, the difference in the…