Medium And Magnetic Effects In Strange Stars

From the history of neutron star, the theory is earlier than the observation. Then more and more advanced instruments and observations deepen the people's understanding of it. At the beginning of the article, we enumerate some observational phenomena and data about the neutron star such as its mass, spin period and Glitch etc.The idea of "neutron star" actually include the concepts of classic neutron star, hybrid star and strange star etc. At the year of 1984, Witten predicted from the theory that the strange quark matter may be the most stable baryon matter in the universe, if this prediction was correct, then the outcome of supernova burst would be very possible the strange star. Many scientists described the most startling prediction from theory and observation in recent yeas.In this article, we describe the dynamic of the strange quark matter concentrating on the existing models including medium effects: density dependent model, chemical potential dependent model and temperature dependent model. Because the mass of quasiparticles are no longer const, the classic thermody-namical relations need to be corrected. So we generally debate the consistent thermodynamic of these models. The bulk viscosity of the strange quark matter is the effective energy damping mechanism and the pivotal parameter determining the r-mode window. We improve the method calculating the bulk viscosity naturally and apply it to the density dependent model.Magnetic is another important parameter of neutron star. The surface radiation of neutron star closely correlated with the magnetic field. We mainly focus on the magnetic effects on the EOS and the stars' cooling. We solve the Dirac function with magnetic field and deduce the thermodynamic potential of the magnetic system. Knowing the exact solution of Dirac function, we calculate the neutrino emissivity of quark Urca reaction and simulate the cooling history of the strange star.Finally, we briefly introduce the unique characters of SGR and AXP dif-ferent from the radio pulsar. And we particularly mention that magnetic field is important to the evolution of these stars. Many problems such as the magnetic production and its distribution in the stars are still open problems.