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arXiv · 1412.7781

Effects of quark chemical equilibration on thermal photon elliptic flow

Akihiko Monnai
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Abstract

Large hadronic elliptic flow $v_2$ is considered as an evidence for the existence of a strongly-coupled QGP fluid in high-energy heavy-ion collisions. On the other hand, direct photon $v_2$ has recently been found to be much larger than hydrodynamic estimations, which is recognized as "photon $v_2$ puzzle". In this study, I discuss the implication of late production of quarks in an initially gluon-rich medium because photons are coupled to quarks. Numerical analyses imply that thermal photon $v_2$ can be visibly enhanced. This indicates that interplay of equilibration processes and collective expansion would be important.

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Akihiko Monnai. 2014-12-25. Effects of quark chemical equilibration on thermal photon elliptic flow. https://doi.org/10.1088/1742-6596%2F612%2F1%2F012026

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