2019/12/12 by I. A. Kondratyev, Kondratyev, I. A., S. G. Moiseenko +5
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #FOS: Physical sciences #Geomagnetism and Paleomagnetism Studies #High Energy Astrophysical Phenomena (astro-ph.HE) #Pulsars and Gravitational Waves Research #Solar and Space Plasma Dynamics
paper · pdf · doi:10.48550/arxiv.1912.05980
openalex publication_date 2019/12/12 · openalex created_date 2020/03/06 · openalex updated_date 2026/07/28
Periodic changes in a thermal soft X-ray flux of a rotating neutron star\nindicate a non-uniform distribution of the surface temperature. A possible\ncause of this phenomenon is a suppression of the heat flux across the magnetic\nfield lines in a crust and an envelope of magnetized neutron stars. In this\npaper we study three-dimensional effects, associated with non-axisymmetric\nmagnetic fields in neutron stars. We calculate the surface temperature\ndistribution by solving numerically a three dimensional heat transfer equation\nin a magnetized neutron star crust. We adopt an anisotropic (tensorial)\nelectron thermal conductivity coefficient, which is derived as an analytical\nsolution of the Boltzmann equation with a Chapman-Enskog method. To calculate\nthe surface temperature distribution, we construct a local one-dimensional\nplane-parallel model ("Ts-Tb"-relationship) of a magnetized neutron star\nenvelope. We then use it as an outer boundary condition for the\nthree-dimensional problem in the crust to find the self-consistent solution. To\nstudy possible observational manifestations from anisotropic temperature\ndistributions we calculate light curves with a composite black-body model. Our\ncalculations show, that a non-axisymmetric magnetic field distribution can lead\nto the irregular non-sinusoidal shape of a pulse profile as well as in some\ncases a significant amplification of pulsations of the thermal flux in\ncomparison to the pure-dipolar magnetic field configurations.\n