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arXiv · 2603.24219

Why are the dilepton temperatures at the relativistic heavy-ion colliders are constant, T ~ 0.3 GeV?

Horst Stoecker·Leonid M. Satarov·Volodymyr Vovchenko
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Abstract

The STAR collaboration at RHIC and the ALICE collaboration at the LHC have reported dielectron spectra in the intermediate mass region, M = (1-3) GeV, which reveal a strikingly constant, energy-independent emission temperature $T_{IMR} \simeq 0.3~\textrm{GeV}$ over a broad range of collision energies, $\sqrt{s_{NN}} = 27 - 5020~\textrm{GeV}$. This unexpected ''thermostat'' behavior raises fundamental questions: why does the temperature remain constant despite increasing collision energy,and what mechanism governs this apparent universality?

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Horst Stoecker, Leonid M. Satarov, Volodymyr Vovchenko. 2026-03-25. Why are the dilepton temperatures at the relativistic heavy-ion colliders are constant, T ~ 0.3 GeV?. https://arxiv.org/abs/2603.24219

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