Speaker: Travis Dore (Universität Bielefeld)
Title of Talk: The Far-from-equilibrium Search for the QCD Critical Point
Abstract: The conjectured QCD critical point in the nuclear matter phase diagram would be the point which separates the known crossover confinement transition at vanishing baryonic chemical potential from a first-order phase transition at higher chemical potential. Heavy-ion collisions at relatively low center of mass energies offer a way for us to search for signals of such a critical end point by exploiting the hydrodynamic description of the evolution of the nuclear matter and comparing directly with data. However, in order to unambiguously determine its existence, it is necessary to disentangle many different effects such as those driven by event-by-event fluctuations or more systematic uncertainties stemming from our incomplete knowledge of relevant physics. In particular, event-by-event fluctuations lead to a highly non-equilibrium initial state for the hot and dense nuclear matter. Furthermore, we lack precise knowledge about the details of the critical point such as the size and shape of the critical region. We use a simple model to study the effects that different critical regions have on hydrodynamic trajectories both with and without non-equilibrium hydrodynamic effects. We argue that equilibrium hydrodynamic trajectories are a poor guide for studying more realistic evolution evidenced by large changes in thermal entropy within the system. Although viscous effects may push or pull trajectories away from the critical point, there exists a dynamic lensing effect that may focus trajectories towards the critical region.
Venue (HYBRID-EVENT): Goldene Box, Physikalisches Institut, INF 226, 69120 Heidelberg AND all talks will also be streamed via the permanent Zoom-link:
Meeting ID: 946 0240 1603
14:00-14.15 discussion and questions
The aim of the YRC Lunch Seminar is to promote individual research done by young researchers within Isoquant and create a regular platform to socialize and share ideas.