1. Nuclear Physics Seminar

    "Jet quenching tests of the QCD Equation of State"

    Presented by Xabier Feal, BNL

    Tuesday, March 10, 2020, 11 am
    Small Seminar Room, Bldg. 510

    Hosted by: Rongrong Ma

    We re-analyze the bremsstrahlung problem in a background field consisting of several sources. We explain how these processes can be represented as a sum of diagrams, generally interfering and thus leading to the well known LPM effect. Then we show how these diagrams can be properly resummed at high energies to go beyond the most common approximations in phenomenological analyses to date: the perturbative (GLV), the Gaussian (BDMPS) or the semi-infinite medium (AMY) approximations. Finally we present some QED and QCD results, and show how the improvement is able to cure some of the puzzles found in data, namely the temperature issues in the determination of the QGP color opacity, encoded usually in the transport coefficient, $\hat{q}$. This finding indicates that full resummations are required for a proper extraction of the QCD matter parameters, and may open up an additional handle on the study of the QCD Equation of State.