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arXiv · 2209.05267

Enhanced dilepton emission from a phase transition in dense matter

O. Savchuk·A. Motornenko·J. Steinheimer·V. Vovchenko·M. Bleicher·M. Gorenstein·T. Galatyuk
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Abstract

It is demonstrated that the presence of a phase transition in heavy ion collisions, at beam energies that probe dense QCD matter, leads to a significant enhancement of the dilepton yield per produced pion due to the extended emission time. In addition, the temperature of low mass dileptons shows a modest decrease due to the mixed phase. The emission of dileptons in the SIS18-SIS100 beam energies range is studied by augmenting the UrQMD transport model with a realistic density dependent equation of state, as well as two different phase transitions. This is achieved by extending the molecular dynamics interaction part of the UrQMD model to a density dependent interaction potential with a high density minimum leading to a phase transition and metastable coexisting high density states. Together with a high precision measurement these simulations will be able to constrain the existence of a phase transition in QCD up to densities of several times nuclear saturation density.

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O. Savchuk, A. Motornenko, J. Steinheimer, V. Vovchenko, M. Bleicher, M. Gorenstein, T. Galatyuk. 2022-09-12. Enhanced dilepton emission from a phase transition in dense matter. https://arxiv.org/abs/2209.05267

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