Absolute emission altitude of pulsars: PSRs B1839+09, B1916+14 and B2111+46

TL;DR

This study estimates the absolute emission altitudes of core and conal components in three pulsars, revealing nested core-cone structures and the effects of aberration-retardation phase shifts on emission profiles.

Contribution

It provides a novel method to determine absolute emission altitudes using A/R phase shifts and Gaussian fitting of emission components in pulsar profiles.

Findings

Emission beams have nested core-cone structures.

Core and conal emission altitudes are estimated relative to the neutron star center.

A/R phase shifts cause symmetric shifts in profile features.

Abstract

We study the mean profiles of the multi--component pulsars PSRs B1839+09, B1916+14 and B2111+46. We estimate the emission height of the core components, and hence find the absolute emission altitudes corresponding to the conal components. By fitting Gaussians to the emission components, we determine the phase location of the component peaks. Our findings indicate that the emission beams of these pulsars have the nested core--cone structures. Based on the phase location of the component peaks, we estimate the aberration--retardation (A/R) phase shifts in the profiles. Due to the A/R phase shift, the peak of the core component in the intensity profile and the inflection point of the polarization angle swing are found to be symmetrically shifted in the opposite directions with respect to the meridional plane in such a way that the core shifts towards the leading side and the polarization angle inflection point towards the trailing side. We have been able to locate the phase location of the meridional plane and to estimate the absolute emission altitude of both the core and the conal components relative to the neutron star centre, using the exact expression for the A/R phase shift given by Gangadhara (2005).