D3-D7 quark-gluon plasmas at finite baryon density

We present the string dual to SU(N-c) N = 4 SYM, coupled to N-f massless fundamental flavors, at finite temperature and baryon density. The solution is determined by two dimensionless parameters, both depending on the 't Hooft coupling lambda(h) at the scale set by the temperature T: o(h) similar to lambda N-h(f)/N-c, weighting the backreaction of the flavor fields and (delta) over tilde similar to lambda(-1/2)(h) nb/(NfT3), where n(b) is the baryon density. For small values of these two parameters the solution is given analytically up to second order. We study the thermodynamics of the system in the canonical and grand-canonical ensembles. We then analyze the energy loss of partons moving through the plasma, computing the jet quenching parameter and studying its dependence on the baryon density. Finally, we analyze certain optical properties of the plasma. The whole setup is generalized to non abelian strongly coupled plasmas engineered on D3-D7 systems with D3-branes placed at the tip of a generic singular Calabi-Yau cone. In all the cases, fundamental matter fields are introduced by means of homogeneously smeared D7-branes and the flavor symmetry group is thus a product of abelian factors.