Journal article

Publication year: 2022

Journal: Physics Letters B

Volume number: 827

ISSN: 0370-2693

eISSN: 1873-2445

Open access status: Gold

DOI Link: https://doi.org/10.1016/j.physletb.2022.136891

Publisher: Elsevier

Abstract: 
The creation of loosely bound objects in heavy ion collisions, e.g. light clusters, near the phase transition temperature (T-ch approximate to 155 MeV) has been a puzzling observation that seems to be at odds with Big Bang nucleosynthesis suggesting that deuterons and other clusters are formed only below a temperature T approximate to 0.1 - 1 MeV. We solve this puzzle by showing that the light cluster abundancies in heavy ion reactions stay approximately constant from chemical freeze-out to kinetic freeze-out. To this aim we develop an extensive network of coupled reaction rate equations including stable hadrons and hadronic resonances to describe the temporal evolution of the abundancies of light (anti-)(hyper-)nuclei in the late hadronic environment of an ultrarelativistic heavy ion collision. It is demonstrated that the chemical equilibration of the light nuclei occurs on a very short timescale as a consequence of the strong production and dissociation processes. However, because of the partial chemical equilibrium of the stable hadrons, including the nucleon feeding from Delta resonances, the abundancies of the light nuclei stay nearly constant during the evolution and cooling of the hadronic phase. This solves the longstanding contradiction between the thermal fits and the late stage coalescence (and the Big Bang nucleosynthesis) and explains why the observed light cluster yields are compatible with both a high chemical production temperature and a late state emission as modeled by coalescence. We also note in passing that the abundancies of the light clusters in the present approach are in excellent agreement with those measured by ALICE at LHC. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).

Harvard Citation style: Neidig, T., Gallmeister, K., Greiner, C., Bleicher, M. and Vovchenko, V. (2022) Towards solving the puzzle of high temperature light (anti)-nuclei production in ultra-relativistic heavy ion collisions, Physics Letters B, 827, Article 136891. https://doi.org/10.1016/j.physletb.2022.136891

APA Citation style: Neidig, T., Gallmeister, K., Greiner, C., Bleicher, M., & Vovchenko, V. (2022). Towards solving the puzzle of high temperature light (anti)-nuclei production in ultra-relativistic heavy ion collisions. Physics Letters B. 827, Article 136891. https://doi.org/10.1016/j.physletb.2022.136891