WIDG Seminar: Anthony Hodges, Georgia State, “Quantifying Properties of the Quark-Gluon Plasma via Jet Modification”

Event time: 
Tuesday, May 25, 2021 - 1:00pm to 2:00pm

Event description: 

The study of jet modification is a critical tool for understanding the properties of the hot, dense medium created in ultra-relativistic heavy ion collisions known as the Quark-Gluon Plasma. Jets are collimated sprays of energetic particles that result from the fragmentation of hard-scattered partons. However, in heavy-ion collisions, the partons that create these jets traverse the QGP medium, losing energy either by interaction with the internal color field, or by collisions with the other constituents of the medium. Because their parent partons have been modified by these interactions, so too are the jets that we measure in heavy-ion collisions. In this talk I will show results quantifying jet-energy loss via two-particle correlations, in which a high momentum trigger particle is used as a proxy for a jet, and all the charged hadrons within an event are correlated spatially to it via the azimuthal separation angle between the particles. Results showing modifications to the per-trigger yield of hadrons and their spatial distribution via I_AA and the Gaussian width, respectively, will be shown for both neutral-pion and direct-photon triggered correlations. Additionally, a new way to probe substructure, the I_AA measured as a function of separation angle, will be shown for neutral-pion triggered correlations. Lastly, I will discuss the progress on measuring neutral pion and direct-photon triggered correlations in the PHENIX detector’s largest heavy-ion data set taken in 2014 as well as the construction of the sPHENIX detector’s hadronic calorimetry subsystem.