相关论文: Direct photon production from viscous QGP

The process of exclusive vector meson production (gamma gamma to J/psi rho^0) is studied for almost real photons. This process may be reduced to photoproduction of J/psi off the rho^0 meson. We discuss the possibility of extracting the…

We calculate medium photons due to Compton and annihilation processes in an anisotropic media. The effects of time-dependent momentum-space anisotropy of {\em Quark-Gluon-Plasma} (QGP) on the medium photon production are discussed. Such an…

We analyze the capability of prompt photon production in pp and pp(bar) collisions to constrain the gluon distribution of the proton, considering data from fixed-target experiments as well as collider measurements. Combined fits are…

We discuss the latest theoretical results on direct photon and dilepton production from relativistic heavy-ion collisions. While the dilepton spectra at low invariant mass show in-medium effects like a collisional broadening of the vector…

Production of lepton pairs in gamma p -> e-e+ p reaction is studied at photon energies up to 1 GeV. We show that even if lepton charge is not measured there are extensive kinematical regimes where the nuclear process dominates over the…

The differential cross section for the production of direct photons in p+p collisions at sqrt(s)=200 GeV at midrapidity was measured in the PHENIX detector at the Relativistic Heavy Ion Collider. Inclusive-direct photons were measured in…

We discuss the shortcomings of a formula that has been used in the literature to compute the number of photons emitted by a hot or dense system during a finite time, and show that the transient effects it predicts for the photon rate are…

The production of electroweak bosons (photons, W and Z particles) in PbPb and pp collisions at sqrt(s) = 2.76 TeV per interacting nucleon pair has been measured with the CMS detector at the LHC. Direct photon production is studied using…

Production of electron-positron pairs with invariant masses less than 300 MeV from thermalized hadronic matter in relativistic heavy ion collisions is calculated using a soft virtual photon approximation. The general theoretical framework…

The measurements of direct photons in $1.0 < p_{T} < 5.0 $GeV/$c$ for p+p and Au+Au collisions have been made through the virtual photon method at PHENIX. The fraction of the virtual direct photon component to the inclusive $e^{+}e^{-}$…

Direct photons have been measured with the PHENIX experiment in Au+Au collisions at $\sqrt{s_\mathrm{NN}}$ = 200 GeV. The direct photon result obtained with PHENIX-EMCal up to 18 GeV/$c$ is consistent with the NLO pQCD calculation scaled by…

We compute the soft real photon emission rate from the QCD matter in the vicinity of the critical line at moderate density and the temperature approaching the critical one from above. The obtained production rate exhibits a steep rise close…

In this proceedings, I consider two-loop contributions to real photon production in thermal QCD. If the photon is strictly massless, strong collinear divergences appear in this calculation. These singularities are regularized by the quark…

We present comparisons of high-pT photon and pion production in hadronic interactions with expectations from next-to-leading order perturbative QCD (NLO pQCD). We also comment on phenomenological models of kT smearing (which approximate…

Direct photon produced from first proton-neutron ($p$-$n$) collision during the early stage of heavy ion reaction is a sensitive probe to reflect energy and momentum distribution of nucleons. In this work, we embedded the hard photon…

Direct photons were measured with the PHENIX experiment in p+p, d+Au, and Au+Au at sqrt(s_NN) = 200 GeV. To tackle the p_T region below 5 GeV/c, direct photons were measured through their internal conversion into e^+e^- in Au+Au collisions.

A theoretical derivation of photon bremsstrahlung, induced by the interactions of an energetic quark in a hot and dense quark-gluon plasma, is given in the framework of the reaction operator approach. For the physically relevant case of…

Starting with the de Broglie--Proca Lagrangian for a massive vector field, we calculate the number density of particles resulting from gravitational particle production (GPP) during inflation, with detailed consideration to the evolution of…

Direct photon emission in heavy-ion collisions is calculated within the relativistic microscopic transport model UrQMD. We compare the results from the pure transport calculation to a hybrid-model calculation, where the high-density part of…

This work calculates the first correction to the leading order q\={q} dilepton production rates due to shear viscosity in an expanding gas. The modified rates are integrated over the space-time history of a viscous hydrodynamic simulation…