Relativistic Binary Pulsar B1913+16: Thirty Years of Observations and Analysis

TL;DR

This paper presents thirty years of observations of the binary pulsar PSR B1913+16, confirming predictions of general relativity through measurements of orbital decay and relativistic effects.

Contribution

It provides detailed measurements of relativistic effects in a binary pulsar system, including stellar masses and orbital decay, with improved accuracy and modeling of the pulsar's beam structure.

Findings

Orbital period decay matches general relativity predictions within 0.2%.

The pulsar's beam is elongated latitudinally and pinched longitudinally.

Systematic uncertainties limit further precision improvements.

Abstract

We describe results derived from thirty years of observations of PSR B1913+16. Together with the Keplerian orbital parameters, measurements of the relativistic periastron advance and a combination of gravitational redshift and time dilation yield the stellar masses with high accuracy. The measured rate of change of orbital period agrees with that expected from the emission of gravitational radiation, according to general relativity, to within about 0.2 percent. Systematic effects depending on the pulsar distance and on poorly known galactic constants now dominate the error budget, so tighter bounds will be difficult to obtain. Geodetic precession of the pulsar spin axis leads to secular changes in pulse shape as the pulsar-observer geometry changes. This effect makes it possible to model the two-dimensional structure of the beam. We find that the beam is elongated in the latitude direction and appears to be pinched in longitude near its center.