PoS - Proceedings of Science
Volume 390 - 40th International Conference on High Energy physics (ICHEP2020) - Parallel: Heavy Ions
Dielectron production: QGP versus photon -- photon mechanism
W. Schaefer
Full text: pdf
Pre-published on: February 09, 2021
Published on: April 15, 2021
Abstract
We summarize recent work, where we calculated the cross sections for dilepton production by photon-photon processes in ultrarelativistic heavy-ion collisions from low (SPS) to high (LHC) energy.
We concentrate on very low pair transverse momenta, $P_T<0.15 \, \rm{GeV}$. Specifically, we investigate the interplay of thermal radiation with initial photon annihilation processes, $\gamma \gamma \to l^+ l^-$, triggered by the coherent electromagnetic fields of the incoming nuclei. For the thermal radiation, we employ the emission from the QGP and hadronic phases with in-medium vector spectral functions which describes the inclusive excess radiation observed over a wide range of collision energies.

We also discuss an approach to the impact-parameter dependent $P_T$-distribution of lepton pairs, which involves a Wigner transform of
the density matrix of Weizs\"acker--Williams photons.
DOI: https://doi.org/10.22323/1.390.0566
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.