Seminars 李政道研究所-粒子核物理研究所联合演讲

Multi-messenger heavy-ion collision physics at beam energy scan energies

by Dr Lipei Du (McGill/UC Berkeley/LBNL)

Tsung-Dao Lee Institute/N6F-N600 - Lecture Room (Tsung-Dao Lee Institute)

Tsung-Dao Lee Institute/N6F-N600 - Lecture Room

Tsung-Dao Lee Institute



Heavy-ion collisions at beam energy scan (BES) energies are essential for probing the QCD phase diagram. Multi-messenger studies of heavy-ion collisions, including hadrons and electromagnetic probes, can reveal the properties of the created QCD matter from different perspectives. In this talk, I will first briefly discuss the importance of rapidity-dependent hadron measurements in constraining the dynamical properties of heavy-ion collisions at BES. Then, I will focus on dileptons, which serve as an electromagnetic probe and a unique probe of the QCD matter. By comparing the effective temperature derived from the thermal dilepton invariant mass spectrum with the average temperature of the fluid, we provide a robust quantitative validation of dileptons as an effective probe of the early stage of heavy-ion collisions. This helps address a long-standing question, namely, how to measure the temperature of the evolving QCD fireball in a way that is unaffected by dynamical distortions. It has taken many decades of progress in both theory and modeling to reach this stage, marking a significant step in our understanding of the initial properties of QCD matter.

Dr. Lipei Du is currently a Postdoctoral Fellow at McGill University and a Postdoctoral Scholar at UC Berkeley, where he is affiliated with LBNL. He obtained his PhD from Ohio State University in 2021 before joining the nuclear theory group at McGill. His research interests primarily focus on the multi-stage description and electromagnetic probes of heavy-ion collisions at the beam energy scan. At Berkeley Lab, he applies Machine Learning-based methods to characterize the properties of the quark-gluon plasma, utilizing multi-messenger probes such as hadrons and jets.

Host: Prof. Shu Li

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