Instability of quark matter core in a compact newborn neutron star with moderately strong magnetic field

Abstract

PACS numbers : 26.60.+c, 97.60.Jd, 76.60.Jx It is explicitly shown that if phase transition occurs at the core of a newborn neutron star with moderately strong magnetic field strength, which populates only the electron's Landau levels, then in the β-equilibrium condition, the quark core is energetically much more unstable than the neutron matter of identical physical condition. *

Response of strongly interacting matter to a magnetic field: Some exact results

“…In contrast to the temperature and chemical potential, the magnetic field that can be achieved in nature seems to be always small compared to the strong scale (perhaps as large as ∼ 10 18 G in magnetars [2,3]). This means that the effect of magnetic field on the medium, in most cases, can be treated as a small perturbation, and the linear response theory is appropriate.…”

“…The fermion spectrum can be found by solving the Dirac equation iγ • DQ = EQ with D µ = ∂ µ − iqA µ , where, q is the electric charge of the quark Q = (u, d), q u = −q d = 1 2 . The axial-vector current can then be directly calculated as a thermal expectation value of (2).…”

“…18 G in magnetars [2,3]). This means that the effect of magnetic field on the medium, in most cases, can be treated as a small perturbation, and the linear response theory is appropriate.…”

Investigation of the field-induced ferromagnetic phase transition in spin-polarized neutron matter: A lowest order constrained variational approach

“…The strong magnetic field could have important influences on the interior matter of a neutron star. Many works have dealt with study of the magnetic properties and equation of state of the neutron star matter [9][10][11][12][13][14][15][16][17][18][19][20] and quark star matter [21][22][23][24][25][26] in the presence of strong magnetic fields. Some authors have considered the influence of strong magnetic fields on the neutron star matter within the mean field approximation [9,12].…”

Surface structure of quark stars with magnetic fields

“…and take B = 4.414 × 10 13 G (corresponding to b = 1) as an upper limit on the surface magnetic field of quark stars. Although higher fields may exist in magnetars and AXPs (anomalous X-ray pulsars), their interior magnetic fields would likely be large enough to inhibit the formation of quark matter [25]. For a given magnetic field, both temperature and matter density determine the filling fraction of the Landau levels, and hence the degree of quantization.…”