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Electron-positron pairs from thermal resonances in ultrarelativistic nuclear collisions

John J. Neumann·David Seibert·George Fai
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Abstract

We use a boost-invariant one-dimensional (cylindrically symmetric) fluid dynamics code to calculate $e^+e^-$ production from $ρ^0$ and $ω$ decay in the central rapidity region of a central S+Au collision at $\sqrt{s}=20$ GeV/nucleon. We use equations of state with a first-order phase transition between a massless pion gas and quark gluon plasma, with transition temperatures in the range $150-200$ MeV. The production cross section at the $ρ$ mass loosely constrains the transition and freeze-out temperatures, and we find that the $m_T$ spectrum is a good thermometer for sufficiently high $T_c$.

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John J. Neumann, David Seibert, George Fai. 1995-11-16. Electron-positron pairs from thermal resonances in ultrarelativistic nuclear collisions. https://doi.org/10.1103/physrevc.53.14

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