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arXiv · 1408.3674

Phenomenology of photon and di-lepton production in relativistic nuclear collisions

E. L. Bratkovskaya
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Abstract

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 meson spectral functions, the dilepton yield at high invariant masses (above 1.1 GeV) is dominated by QGP contributions for central heavy-ion collisions at relativistic energies. The present status of the photon $v_2$ "puzzle" - a large elliptic flow $v_2$ of the direct photons experimentally observed at RHIC and LHC energies - is also addressed. The role of hadronic and partonic sources for the photon spectra and $v_2$ is considered as well as the possibility to subtract the QGP signal from the experimental observables.

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E. L. Bratkovskaya. 2014-08-15. Phenomenology of photon and di-lepton production in relativistic nuclear collisions. https://doi.org/10.1016/j.nuclphysa.2014.09.088

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