Heating and cooling of magnetars with accreted envelopes
نویسندگان
چکیده
We study the thermal structure and evolution of magnetars as cooling neutron stars with a phenomenological heat source in an internal layer. We focus on the effect of magnetized (B 1014 G) non-accreted and accreted outermost envelopes composed of different elements, from iron to hydrogen or helium. We discuss a combined effect of thermal conduction and neutrino emission in the outer neutron star crust and calculate the cooling of magnetars with a dipole magnetic field for various locations of the heat layer, heat rates and magnetic field strengths. Combined effects of strong magnetic fields and light-element composition simplify the interpretation of magnetars in our model: these effects allow one to interpret observations assuming less extreme (therefore, more realistic) heating. Massive magnetars, with fast neutrino cooling in their cores, can have higher thermal surface luminosity.
منابع مشابه
Cooling Neutron Stars with Accreted Envelopes
Gilles Chabrier1, Alexander Y. Potekhin2;1;3, and Dmitry G. Yakovlev2 ABSTRACT The relationships between the e ective surface temperature Te and internal temperature Tb of nonmagnetized neutron stars with and without accreted envelopes are calculated for Te > 5 104 K. We use updated equations of state and radiative opacities, and we improve considerably the electron conductive opacity. We exami...
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