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

Analysis of 10 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, b , determined at the 1.5% level of precision ( D k = 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 b allows a limit on the variation of Newton's gravitational constant, |Ġ/ G | ⩽ 23 × 10 −12 yr −1 . We also constrain any anomalous acceleration along the line of sight to the pulsar to | a ☉ / c | ⩽ 1.5 × 10 −18 s −1 at 95% confidence, and derive a pulsar mass, m psr = 1.76 ± 0.20 M ☉ , one of the highest estimates so far obtained.