We investigate the influence of a homogeneus and constant strong external magnetic field on the heavy-meson spectrum. Quarkonium states cc and bb are described within a non-relativistic framework and by means of a suitable potential model based on the Cornell parametrization. In particular, in this work we propose a model which takes into account the possible anisotropies emerging at the level of the static quark-antiquark potential, as observed in recent lattice studies. The investigation is perfomed both with and without taking into account the anisotropy of the static potential, in order to better clarify its effects.

We investigate the static QQ potential at zero and finite temperature in the presence of a constant and uniform external magnetic field B→, for several values of the lattice spacing and for different orientations with respect to B→. As a byproduct, we provide continuum limit extrapolated results for the string tension, the Coulomb coupling and the Sommer parameter at T=0 and B=0. We confirm the presence in the continuum of a B-induced anisotropy, regarding essentially the string tension, for which it is of the order of 15% at |e|B∼1 GeV2 and would suggest, if extrapolated to larger fields, a vanishing string tension along the magnetic field for GeV2. The angular dependence for GeV2 can be nicely parametrized by the first allowed term in an angular Fourier expansion, corresponding to a quadrupole deformation. Finally, for T≠0, the main effect of the magnetic field is a general suppression of the string tension, leading to a early loss of the confining properties: this happens even before the appearance of inverse magnetic catalysis in the chiral condensate, supporting the idea that the influence of the magnetic field on the confining properties is the leading effect originating the decrease of Tc as a function of B

We present results for the (color)magnetic and (color)electric screening masses of the Quark-Gluon Plasma in the presence of an external magnetic field. The screening masses are extracted from the correlators of Polyakov loops, determined by lattice QCD simulations at the physical point. We explore temperatures in the range 200 MeV T 330 MeV and magnetic field intensities up to |e|B ∼ 1.3 GeV 2 . We find that both screening masses are increasing functions of the magnetic field and that the dependence on B becomes weaker for larger temperatures. In the case of the magnetic screening mass a slight anisotropy is also observable.