Direct photon interferometry

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 and discuss possibilities of measurement of the photon Bose-Einstein correlations in ongoing and future experiments.Comment: 6 pages, prepared for the Proceedings of Workshop on Particle Correlations and Femtoscopy (WPCF), Kromeriz, Czech Republic, August 15-17, 2005. Ref. adde

Photon Physics in ALICE

We give an overview of photon physics which will be studied by the ALICE experiment in proton-proton and heavy ion collisions at LHC. We compare properties of ALICE photon detectors and estimate their ability to measure neutral meson and direct photon spectra as well as gamma-hadron and gamma-jet correlations in pp and Pb+Pb collisions.Comment: 4 pages, 3 figures - To appear in the conference proceedings for Quark Matter 2009, March 30 - April 4, Knoxville, Tennesse

Direct photons at low pTp_{T} measured in PHENIX

Direct photon spectra measured at small $p_T$ in p+p, d+Au and Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV are presented. Several measurement techniques including statistical subtraction, tagging, and internal and external conversion were applied and found to produce consistent results. The p+p and d+Au results are found to be in very good agreement with pQCD predictions over the entire $p_T$ range. No excess of direct photons in Au+Au collisions with respect to binary scaled d+Au data is observed within systematic errors.Comment: 4 pages, 3 figures, proceedings for Quark Matter 200

Photon emission in Pb+Pb collisions at SpS and LHC

Yield of direct photons in Pb+Pb collisions at SpS and LHC energy is evaluated with emphasis on estimate of possible uncertainty. Possibility of experimental observation of direct photons at LHC is discussed. Predictions of several models at SpS energy are compared with experimental data.Comment: 19 pages, 13 figure

Direct photon spectra in Pb-Pb at sqrt(s) = 5.5 TeV: hydrodynamics+pQCD predictions

The transverse momentum spectra for direct photons produced in Pb-Pb collisions at the LHC, including thermal (hydrodynamics) and prompt (pQCD) emissions are presented.Comment: 2 pages, 2 figures. Contribution to "Workshop on Heavy Ion Collisions at the LHC: Last Call for Predictions", Geneva, Switzerland, 14 May - 8 Jun 2007. To appear in J.Phys.

Identified hadron spectra in Pb-Pb at sqrt(s) = 5.5 TeV: hydrodynamics+pQCD predictions

The single inclusive charged hadron pT spectra in Pb-Pb collisions at the LHC, predicted by a combined hydrodynamics+perturbative QCD (pQCD) approach are presented.Comment: 2 pages, 2 figures. Contribution to "Workshop on Heavy Ion Collisions at the LHC: Last Call for Predictions", Geneva, Switzerland, 14 May - 8 Jun 2007. To appear in J.Phys.