Medium evolution of a static quark-antiquark pair in the large Nc limit

Round table on open quantum systems

“…It is possible that these operators have a complicated time-ordering because of the mixing between the two branches of the Schwinger-Keldysh contour. In fact, this kind of operators emerge on the study of the evolution of a static pair in a plasma [28]. It is not clear how these operators can be computed on lattice QCD, but that does not mean that it can not be done.…”

Medium evolution of a static quark-antiquark pair in the large Nc limit

“…Heavy quarks have a mass m that is much larger than ⇤ QCD and the temperature of the medium. Other relevant energy scales, are the inverse of the typical radius 1 r ⇠ mv (with v ⌧ 1) and the binding energy E ⇠ mv 2 . Therefore, quarkonium is a system in which several well-separated energy scales are present.…”

“…Instead, we have a spinor field for heavy quarks and another spinor field for the antiquarks. One can also integrate out the scale 1 r to go from NRQCD to potential NRQCD (pNRQCD) [9]. The pNRQCD Lagrangian at T = 0 is…”

“…Our motivation in this work is to gain information about the master equation in more general settings. More specifically, we ask ourselves if it is possible to know something about the master equation in the case 1 r ⇠ T beyond the perturbative regime. We expect that the needed non-perturbative medium information can be encoded in expectation values of gauge invariant operators.…”

“…This allows us to learn lessons that are useful to simplify phenomenological models of quarkonium in a plasma. More details can be found in [1].…”