Speaker
Mr
Amit Kumar
(Wayne State University)
Description
The jet transport coefficient $\hat{q}$ is the leading parameter that controls the modification of hard jets produced in heavy-ion collisions. This coefficient, like other jet coefficients is inherently non-perturbative, and hence, is challenging to compute from first principles. Currently, existing theoretical model to data comparisons require a separate normalization of $\hat{q}$ between RHIC and LHC energies, beyond the obvious $T^{3}$ scaling from dimensional arguments. This is known as the jet $\hat{q}$ puzzle. In this talk, we present a pQCD and lattice gauge theory based formulation to study $\hat{q}$ which sheds new light on the non-perturbative nature of $\hat{q}$ and the jet puzzle. For this first attempt, we formulate $\hat{q}$ within a quenched SU(3) lattice. We consider a leading order diagram for a hard parton passing through the thermal medium. The non-perturbative part is expressed in terms of a non-local (two-point) Field-Strength-Field-Strength operator product which can be Taylor expanded after analytic continuation to the Euclidean region. Such an expansion allowed us to write $\hat{q}$ in terms of the expectation of local operators. We also carry out a perturbative analysis both on the lattice and in continuum field theory to understand the scale dependence of the jet transport coefficient.
Primary authors
Dr
Abhijit Majumder
(Wayne State University)
Mr
Amit Kumar
(Wayne State University)