Quark Matter In Magnetic Field

The study of strong interacting matter,especially the symmetry breaking and resto-ration and the corresponding phase transitions is one of the important topics of theoretical physics today.With the development of such studies,it is natural that people begin to consider more degrees of freedom,such as chiral chemical potential and magnetic field.These degrees of freedom greatly enrich the phase structure of QCD and deepen our understanding of QCD matter.The results also have important application in astronomy,particle physics and condensed matter physics.At the same time,relativistic heavy ion collisions serve as an important experimental method to study QCD matter.The mag-netic fields created in such collisions,and the interaction with the QCD matter,are very important.We studied the interaction between magnetic field and quark matter.Using a potential model,we study one of the important signals in relativistic heavy ion collisions:charmonia and the magnetic field effect.We consider the sources of elliptic flow of charmonia in different momentum regions,and do calculations within the model,especially for the charmonia in high transverse momentum region.By using Sch?rdinger equation to describe the evolution of c?c pairs in magnetic field,and combining it with a phenomenological model of charmonium formation,we get a non-collective elliptical v₂for high transverse momentum J/?s.The result is in consistence with experimental data.On the basis of 3+1D ideal hydrodynamics model,by introducing current conservation equations and anomalous transport terms,we establish a non-perturbative hydrodynamics model to describe chiral magnetic effect and chiral vortical effect simultaneously.Using that model,we calculate the charge and baryon number separation effect,and the related two-particle correlations of identified particles.We find that at RHIC energy and mode-rate centrality,the CME and CVE are comparable,and they can explain the experimental results reasonably.We also study the fermion Wigner function in external electromagnetic field.From Nambu-Jona-Lasino Lagrangian,we get the kinetic equations for equal-time fermion Wigner functions in and beyond chiral limit.Using semi-classical expansion,we solve these equations to the 1st order in.For massive fermions,we study the breaking of chiral and U_A?1?symmetry in electromagnetic field.We find that the electromagnetic field breaks U_A?1?symmetry only after considering quantum correlation.We also find strong oscillation effect on chiral condensate and?condensate.In chiral limit,we derive the chiral transport equation,which is equivalent to the transport equation of Wigner function up to the 1st order in.