Anomalous QCD Contribution to the Debye Screening in an External Field via Holography

Abstract

In this paper we discuss the QCD contribution to the Abelian Debye and magnetic screening masses in a deconfined QCD plasma at finite temperature in the presence of an external magnetic field B. We use a holographic AdS/QCD setup in an AdS Schwarzschield black hole background and show that the electric screening mass has a form similar to the one-loop result in QED. Moreover, we calculate the corrections due to the magnetic field to all orders of B and demonstrate that in the case when magnetic field is large the Debye mass grows linearly with B, while the magnetic screening mass vanishes. The whole effect of the magnetic field turns out to stem from the Chern-Simons action. We also discuss the zero temperature case in the chiral perturbation theory.

Comments: 20 pages, 3 figures, 2nd version: the field normalization improved, result for zero field (11) altered