Thermal properties of the middle-aged pulsar J1741-2054

Abstract

We present results of the spectral analysis of the X-ray emission from the middle-aged Fermi pulsar J1741$-$2054 using all Chandra archival data collected in 2010 and 2013. We confirm early findings by Romani et al. 2010 that the pulsar spectrum contains a thermal emission component. The component is best described by the blackbody model with the temperature $\approx$ 60 eV and the emitting area radius $\approx$ 17 $D_{\rm kpc}$ km. The thermal emission likely originates from the entire surface of the cooling neutron star if the distance to the pulsar is $\approx$ 0.8 kpc. The latter is supported by a large absorbing column density inferred from the X-ray fit and empirical optical extinction--distance relations along the pulsar line of sight. The neutron star surface temperature and characteristic age make it similar to the well studied middle-aged pulsar B1055$-$52. Like the latter PSR J1741$-$2054 is hotter than the standard cooling scenario predicts.