https://doi.org/10.1051/epjconf/202531607008
Directed Flow of Λ, Λ3H and Λ4H in Au+Au collisions at √sNN = 3.2, 3.5, 3.9 and 4.5 GeV at RHIC
1 Central China Normal University
2 Heidelberg University
* e-mail: JYHan@mails.ccnu.edu.cn
Published online: 27 January 2025
Studying hyper-nuclei yields and their collectivity can shed light on their production mechanism as well as the hyperon-nucleon interactions. Heavy-ion collisions from the RHIC beam energy scan phase II (BES-II) provide an unique opportunity to understand these at high baryon densities. In these proceedings, we present a systematic study on energy dependence of the directed flow (v1) for Λ and hyper-nuclei (3ΛH and 4ΛH) from mid-central Au+Au collisions at √sNN = 3.2, 3.5, 3.9 and 4.5 GeV, collected by the STAR experiment with the fixed-target mode during BES-II. The rapidity (y) dependence of the hyper-nuclei v1 is studied in mid-central collisions. The extracted v1 slopes (dv1/dy|y=0) of the hyper-nuclei are positive and decrease gradually as the collision energy increases. These hyper-nuclei results are compared to that of light-nuclei including p, d, t/3He and 4He. Finally, these results are compared with a hadronic transport model including coalescence after-burner.
© The Authors, published by EDP Sciences, 2025
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
