Thermodynamics of heavy quarkonium in a magnetic field background
Abstract
We study the effect of magnetic field on heavy quarkantiquark pair in both EinsteinMaxwell (EM) and EinsteinMaxwelldilaton (EMD) model. The interquark distance, free energy, entropy, binding energy, and internal energy of the heavy quarkonium are calculated. It is found that the free energy suppresses and the entropy increases quickly with the increase of the magnetic field B . The binding energy vanishes at smaller distance when increasing the magnetic field, which indicates the quarkantiquark pair dissociates at smaller distance. The internal energy which consists of free energy and entropy will increase at large separating distance for a nonvanishing magnetic field. These conclusions are consistent both in the EM and EMD model. Moreover, we also find that the quarkonium will dissociate easier in the parallel direction than that in the transverse direction for EMD model, but the conclusion is opposite in EM model. Lattice results are in favor of EMD model. Besides, a Coulombpluslinear potential (Cornell potential) can be realized only in EMD model. Thus, a dilaton field is proved to be important in holographic model. Finally, we also show that the free energy, entropy, and internal energy of a single quark in EMD model with the presence of magnetic field.
 Publication:

Physical Review D
 Pub Date:
 October 2020
 DOI:
 10.1103/PhysRevD.102.086020
 arXiv:
 arXiv:2006.09062
 Bibcode:
 2020PhRvD.102h6020Z
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 21 pages, 13 figures