Heavy quarkonia in a medium as a quantum dissipative system:   Master-equation approach
  The problem of the evolution of a heavy quarkonium in a medium can be recast as that of a quantum dissipative system. Within the framework of the master-equation approach to open quantum systems, we consider the real-time dynamics of quarkonia. We find that in a plasma at fixed temperature, the populations of the various quarkonium states evolve together, while their momentum distribution satisfies a Fokker-Planck equation. 
Nicolas Borghini, Clement Gombeaud
nucl-th hep-ph