Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2011-08-10
Phys. Rev. C 84, 054906 (2011)
Physics
High Energy Physics
High Energy Physics - Phenomenology
10 pages, 7 figures
Scientific paper
10.1103/PhysRevC.84.054906
We update our calculations of thermal-photon production in nuclear collisions at the Relativistic Heavy-Ion Collider (RHIC). Specifically, we address the recent experimental observation of an elliptic flow of direct photons comparable in magnitude to that of pions, which is at variance with expectations based on quark-gluon plasma (QGP) dominated photon radiation. Our thermal emission rate is based on previous work, i.e., resummed leading-order QGP emission and in-medium hadronic rates in the confined phase. These rates are nearly degenerate at temperatures close to the expected QCD-phase change. The rates are convoluted over an improved elliptic-fireball expansion with transverse- and elliptic-flow fields quantitatively constrained by empirical light- and strange-hadron spectra. The resulting direct-photon spectra in central Au-Au collisions are characterized by hadron-dominated emission up to transverse momenta of ~2-3 GeV. The associated large elliptic flow in the hadronic phase mitigates the discrepancy with the measured photon-v2 compared to scenarios with QGP-dominated emission.
Gale Charles
Hees Hendrik van
Rapp Ralf
No associations
LandOfFree
Thermal Photons and Collective Flow at the Relativistic Heavy-Ion Collider does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Thermal Photons and Collective Flow at the Relativistic Heavy-Ion Collider, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermal Photons and Collective Flow at the Relativistic Heavy-Ion Collider will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-665234