Measurements of 3 H and 4 H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region
Authors
Abdallah, M. S. ; Aboona, B. E. ; Adam, J. ; Adamczyk, L.; Adams, J. R. ; Adkins, J.; Agakishiev, G.; Aggarwal, I.; Aggarwal, M.; Ahammed, Z; Spinka, H. M.; Underwood, D.G.; Zurek, M.
Abstract
We report precision measurements of hypernuclei 3H and 4H lifetimes obtained from Au+Au collisions at sNN=3.0GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of 3H and 4H midrapidity yields in Au+Au collisions at sNN=3.0GeV. 3H and 4H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 22115(stat)19(syst)ps for 3H and 2186(stat)13(syst)ps for 4H. The pT-integrated yields of 3H and 4H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of 4H is different for 0%10% and 10%50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the 3H yield well, while underestimating the 4H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured 3H and 4H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.