Ambipolar Heating of Magnetars

Abstract

Magnetars, neutron stars thought to be with ultrastrong magnetic fields of 1014–15 G, are observed to be much hotter than ordinary pulsars with ∼1012 G, and additional heating sources are required. One possibility is heating by the ambipolar diffusion in the stellar core. This scenario is examined by calculating the models using the relativistic thermal evolutionary code without making the isothermal approximation. The results show that this scenario can be consistent with most of the observed magnetar temperature data.