Quark Number Susceptibility and Thermodynamics in HTL approximation
  In HTL perturbation theory we obtain leading order quark number susceptibility as a response to an external disturbance, viz., chemical potential (\mu) that generates density fluctuation, which is related to the correlation function through the thermodynamic sum rule associated with the symmetry of the system. We also obtain various thermodynamic quantities in leading order. 
Najmul Haque, Munshi G. Mustafa
hep-ph hep-lat nucl-th