Related papers: Photon and dilepton observables: An experimental o…
Low-mass dilepton spectra as measured in high-energy heavy-ion collisions are a unique tool to obtain spectroscopic information about the strongly interacting medium produced in these reactions. Specifically, in-medium modifications of the…
This work presents measurements of electron-positron pairs from p+p collisions at sqrt(s) = 200 GeV collected during the 2005 RHIC run and compares them to results from Au+Au collisions at sqrt(s_NN) = 200 GeV taken in 2004 with the PHENIX…
The sensitivity of dilepton production in elementary reactions of photons and pions with nuclei on in-medium changes of hadronic properties is studied. It is shown that this sensitivity is comparable to that encountered in ultrarelativistic…
The PHENIX experiment has measured direct photons in $\sqrt{s_{NN}} = 200$ GeV Au+Au collisions and p+p collisions. The fraction of photons due to direct production in Au+Au collisions is shown as a function of $p_T$ and centrality. This…
We attempt, in this paper, to deal with the direct photon production phenomena in $p+p$, $d+Au$ and $Au+Au$ collisions at RHIC energy, $\sqrt{s_{NN}}$ = 200 GeV and in $Pb+Pb$-collisions at LHC energy, $\sqrt{s_{NN}}$ = 2.76 TeV on the…
We discuss properties of photons in extremely strong magnetic fields induced by the relativistic heavy-ion collisions. We investigate the vacuum birefringence, the real-photon decay, and the photon splitting which are all forbidden in the…
Two-photon processes in relativistic heavy-ion collisions have emerged as a critical probe of quantum electrodynamics in ultra-intense electromagnetic fields, with recent focus extending beyond dileptons to hadronic final states. At…
Methods to classify events experimentally according to collision geometry are well established and non-controversial when collisions of large ions are studied. However, high luminosity data from $p/d$+A collisions at RHIC and LHC provided…
We consider recent developments in the theory of the two-photon interferometry in ultrarelativistic heavy ion collisions with emphasis on the difference between photon and hadron interferometry. We review the available experimental results…
We investigate hadrons and direct photon production in pp and pA collisions at the energies of RHIC and LHC within the color-dipole approach employing various saturation models. We show that greatest sensitivity to saturation effects is…
Results are presented of an ongoing analysis of direct photon production in s_(NN)=200GeV deuteron-gold collisions with the STAR experiment at RHIC. A significant excess of direct photons is observed near mid-rapidity 0<y<1 and found to be…
I emphasize in this contribution how prompt photons can be used to probe nuclear parton densities as well as medium-modified fragmentation functions in heavy ion collisions. Various predictions in p-A and A-A collisions at LHC energies are…
Direct photon production is an important observable in heavy ion collisions as photons are penetrating and therefore largely insensetive to final state effects that lead to jet quenching. Measurements of the fragmentation component to…
The azimuthal correlations of direct photons ($\gamma_{_{dir}}$) with high transverse momentum ($p_{_{T}}$), produced at mid-rapidity ($|\eta^{\gamma_{_{dir}}}|<1$) in Au+Au collisions at center-of-mass energy $\sqrt{s_{_{NN}}}=200$~GeV,…
We propose to measure the linear polarization of the external electromagnetic fields of a relativistic heavy ion through azimuthal asymmetries in dilepton production in ultraperipheral collisions. The asymmetries estimated with the…
The recent results at RHIC for direct $\gamma$-charged hadron azimuthal correlations in heavy-ion collisions are presented. We use these correlations to study the color charge density of the medium through the medium-induced modification of…
Electromagnetic probes are excellent messengers from the hot and dense medium created in high-energy heavy-ion collisions. Since leptons do not interact strongly, their spectra reflect the entire space-time evolution of the collision. 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…
We review current results on physics with photons at the LHC and discuss realistic perspectives of photon physics at future colliders. In particular, we focus on Standard Model (SM) measurements with photons at the upcoming high-luminosity…
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…