https://doi.org/10.1140/epja/s10050-024-01273-y
Regular Article - Theoretical Physics
Enhanced Dilepton production near the color superconducting phase and the QCD critical point
1
Department of Physics, Osaka University, 560-0043, Toyonaka, Japan
2
Yukawa Institute for Theoretical Physics, Kyoto University, 606-8502, Kyoto, Japan
3
Akita International University, Yuwa, 010-1292, Akita, Japan
4
Frankfurt Institute for Advanced Studies, Ruth-Moufang-Str. 1, 60438, Frankfurt am Main, Germany
a
nishimura@kern.phys.sci.osaka-u.ac.jp
Received:
8
December
2023
Accepted:
19
February
2024
Published online:
9
April
2024
The dilepton production yields in relativistic heavy ion collisions are investigated along isentropic trajectories in the quark (Wigner) phase within the two-flavor Nambu-Jona-Lasinio model. An enhancement of the ultra-low energy dilepton yield in the vicinity of the color superconducting (CSC) phase and the QCD critical point (QCD-CP) is found, compared to the free quark gas. Furthermore, we have found a nontrivial structure in the beam energy dependence of the ultra-low energy dilepton yield. A local maximum and minimum of the dilepton yield as a function of entropy per baryon emerge when the trajectories are close to both locations of the CSC phase transition line and the QCD-CP. Only the maximum appears in the scenario without the CSC phase but with the QCD-CP. On the other hand, when only the CSC phase is considered, the dilepton yield monotonically increases as the beam energy decreases. These distinctive patterns could potentially serve as signals of the CSC phase and QCD-CP. In addition, it is found that the dilepton production yield and the location of the minimum strongly depend on the value of diquark coupling, suggesting the possibility that the value of the diquark coupling may be extracted from experimental data.
Yasushi Nara and Jan Steinheimer contributed equally to this work
Copyright comment Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
