General relativistic calculation of magnetic field and Power loss for a misaligned pulsar

TL;DR

This paper models a misaligned pulsar as a general relativistic oblique rotator, analyzing magnetic fields and power loss, revealing differences from Newtonian predictions especially at high misalignment angles.

Contribution

It provides a novel general relativistic analysis of magnetic fields and power loss in misaligned pulsars, contrasting with prior Newtonian models.

Findings

Power loss is minimized at aligned or orthogonal configurations.

Magnetic field decreases with increased misalignment.

Electric field remains nearly constant initially but drops at high misalignment.

Abstract

In this study, we model a pulsar as a general relativistic oblique rotator, where the oblique rotator is a rotationally deformed neutron star whose rotation and magnetic axis are inclined at an angle. The oblique rotator spins down, losing rotational energy through the magnetic poles. The magnetic field is assumed to be dipolar; however, the star has a non-zero azimuthal component due to the misalignment. The magnetic field induces an electric field for a force-free condition. The magnetic field decreases as the misalignment increases and is minimum along the equatorial plane of the star. In contrast, the electric field remains almost constant initially but decreases rapidly at a high misalignment angle. The charge separation at the star surface is qualitatively similar to that of Newtonian calculation. We find that the power loss for a general relativistic rotator is minimum for either an aligned or an orthogonal rotator, which contrasts with Newtonian calculation, where the power loss increases with an increase in the misalignment angle.