A Simple Model of Radiation from a Magnetized Neutron Star: Accreted Matter and Polar Hotspots

Abstract

A simple and well known model for thermal radiation spectra from a magnetized neutron star is further studied. The model assumes that the star is internally isothermal and possesses dipole magnetic field (B <= 1e14 G) in the outer heat-insulating layer. The heat transport through this layer makes the surface temperature distribution anisotropic; any local surface element is assumed to emit a blackbody (BB) radiation with a local effective temperature. It is shown that this thermal emission is nearly independent of the chemical composition of insulating envelope (at the same taken averaged effective surface temperature). Adding a slight extra heating of magnetic poles allows one to be qualitatively consistent with observations of some isolated neutron stars.

16 pages, 10 figures; Special Issue of "Universe" entitled: "Advances in the Physics of Stars: In Memory of Prof. Yu. N. Gnedin," edited by N. R. Ikhsanov, G. L. Klimchitskaya, and V. M. Mostepanenko

References in corpus (8)

• Magnetic Hydrogen Atmosphere Models and the Neutron Star RX J1856.5-3754
• Thermal luminosities of cooling neutron stars
• The (Re-)Discovery of G350.1-0.3: A Young, Luminous Supernova Remnant and Its Neutron Star
• A deep XMM-Newton look on the thermally emitting isolated neutron star RX J1605.3+3249
• Modeling Neutron Star Atmospheres
• Middle aged $\gamma$-ray pulsar J1957+5033 in X-rays: pulsations, thermal emission and nebula
• Probing the surface magnetic field structure in RX J1856.5-3754
• Two-blackbody portraits of radiation from magnetized neutron stars