A Population-Informed Mass Estimate for Pulsar J0740+6620

Galactic double neutron star systems have a tight mass distribution around $\sim 1.35 M_{\odot}$, but the mass distribution of all known pulsars is broader. Here we reconstruct the Alsing, et al. (2018) bimodal mass distribution of pulsars observed in binary systems, incorporating data from observations of J0740+6620 which were not available at the time of that work. Because J0740+6620 is an outlier in the mass distribution with non-negligible uncertainty in its mass measurement, its mass receives a large correction from the population, becoming $m_{J0740+6620} = 2.03^{+0.10}_{-0.08} \, M_\odot$ (median and 68\% CI). Stochastic samples from our population model, including population-informed pulsar mass estimates, are available at https://github.com/farr/AlsingNSMassReplication .