Modeling the Pulse Profiles of Millisecond Pulsars in the Second LAT Catalog of gamma-ray Pulsars

TL;DR

This paper models the gamma-ray and radio pulse profiles of about 40 millisecond pulsars using geometric emission models to understand their magnetospheric geometries and emission sites.

Contribution

It introduces a comprehensive fitting approach for MSP pulse profiles with various gamma-ray and radio emission models, providing new insights into pulsar geometries.

Findings

Constraints on pulsar viewing geometries and emission sites.

Identification of trends in the MSP population.

Validation of geometric emission models against observed profiles.

Abstract

Significant gamma-ray pulsations have been detected from ~40 millisecond pulsars (MSPs) using 3 years of sky-survey data from the Fermi LAT and radio timing solutions from across the globe. We have fit the radio and gamma-ray pulse profiles of these MSPs using geometric versions of slot gap and outer gap gamma-ray emission models and radio cone and core models. For MSPs with radio and gamma-ray peaks aligned in phase we also explore low-altitude slot gap gamma-ray models and caustic radio models. The best-fit parameters provide constraints on the viewing geometries and emission sites. While the exact pulsar magnetospheric geometry is unknown, we can use the increased number of known gamma-ray MSPs to look for significant trends in the population which average over these uncertainties.