Radio Pulsars in Binary Systems

TL;DR

This thesis investigates binary radio pulsars, analyzing their evolution, eclipse behavior, and relativistic effects to test gravitational theories and understand pulsar properties.

Contribution

It provides new insights into pulsar eclipse geometry, tests general relativity through eclipse modeling, and constrains pulsar emission geometry via non-detection of latitudinal aberration.

Findings

Pulsar B precesses consistent with general relativity.

Eclipse modeling yields precise pulsar geometry.

Upper limits set on latitudinal aberration in pulsar A.

Abstract

This thesis focuses on the study of binary radio pulsars, their evolution and some specific use of their properties to investigate fundamental physics such as general relativity and other gravitational theories. The work that we present here is organized in three main parts. First, we report on the study of PSR J1744-3922, a binary pulsar presenting a peculiar `flickering' flux behavior as well as spin and orbital properties that do not correspond to the expectations of standard evolution scenarios. Second, we conducted an in-depth analysis of the eclipses in the relativistic double pulsar system PSR J0737-3039A/B. From our modeling of the eclipses, we precisely determined the geometry of pulsar B in space and used this information to study the temporal behavior of the eclipses, which revealed that pulsar B precesses around the angular momentum of the system in a way that is consistent with the prediction of general relativity. Third, we searched for the signature of latitudinal aberration in the pulse profile of pulsar A in the double pulsar system. The non-detection of this effect allows us to put an upper limit on its amplitude, which constrains the geometry of pulsar A with respect to our line of sight as well as its emission geometry. (Abridged)