Precision timing of PSR J0437-4715: an accurate pulsar distance, a high pulsar mass and a limit on the variation of Newton's gravitational constant

TL;DR

This study uses ten years of pulsar timing data to precisely measure the distance and mass of PSR J0437-4715, setting limits on gravitational constant variation and improving astrophysical measurements.

Contribution

It provides a model-independent distance measurement and constrains the variation of Newton's gravitational constant using pulsar timing data.

Findings

Distance to PSR J0437-4715 is 157.0 +/- 2.4 pc.

Pulsar mass is estimated at 1.76 +/- 0.20 solar masses.

Limit on G variation is |Gdot/G| < 23 x 10^{-12} per year.

Abstract

Analysis of ten years of high-precision timing data on the millisecond pulsar PSR J0437-4715 has resulted in a model-independent kinematic distance based on an apparent orbital period derivative, Pbdot, determined at the 1.5% level of precision (Dk = 157.0 +/- 2.4 pc), making it one of the most accurate stellar distance estimates published to date. The discrepancy between this measurement and a previously published parallax distance estimate is attributed to errors in the DE200 Solar System ephemerides. The precise measurement of Pbdot allows a limit on the variation of Newton's gravitational constant, |Gdot/G| < 23 x 10^{-12} 1/yr. We also constrain any anomalous acceleration along the line of sight to the pulsar to |a(Sun)/c| < 1.5 x 10^{-18} 1/s at 95% confidence, and derive a pulsar mass, m(psr) = 1.76 +/- 0.20 M, one of the highest estimates so far obtained.