Jet drift and collective flow in heavy-ion collisions
Logan Antiporda, Joseph Bahder, Hasan Rahman, Matthew D. Sievert
Abstract
We study the tomographic applications of a new phenomenon we dub ``jet drift''---the deflection of high-energy particles and jets toward the direction of a flowing medium---to the quark-gluon plasma produced in heavy-ion collisions. While the physics of jet drift is quite general, for specificity we consider the case of photon-jet production at midrapidity. Beginning with the simplest possible model, a large slab of uniformly flowing plasma, we systematically introduce the geometrical elements of a heavy-ion collision in a simple optical Glauber model. We find that the moving medium causes the jet to drift in the direction of the flow, bending its trajectory and leaving detailed signatures of the flow pattern in the distribution of $\ensuremath{\gamma}+\text{jet}$ acoplanarities. In the elliptical geometries produced in noncentral collisions, this drift effect leads to a strong geometry coupling which persists despite the addition of event-by-event fluctuations in the jet production point, impact parameter, and acoplanarity. We propose a new observable to measure the jet drift effect through the correlation of $\ensuremath{\gamma}+\text{jet}$ acoplanarities with the elliptic flow of soft particles. Preliminary estimates suggest this correlation may be studied at sPHENIX and the LHC.