The Identification of the White Dwarf Companion to the Millisecond Pulsar J2317+1439

S. Dai, M. C. Smith, S. Wang, S. Okamoto, R. X. Xu, Y. L. Yue, J. F. Liu
2017 Astrophysical Journal  
We report identification of the optical counterpart to the companion of the millisecond pulsar J2317+1439. At the timing position of the pulsar, we find an object with $g=22.96\pm0.05$, $r=22.86\pm0.04$ and $i=22.82\pm0.05$. The magnitudes and colors of the object are consistent with it being a white dwarf. By comparing with white dwarf cooling models, we estimate that it has a mass of $0.39^{+0.13}_{-0.10}$ M$_{\odot}$, an effective temperature of $8077^{+550}_{-470}$ K and a cooling age of
more » ... a cooling age of $10.9\pm0.3$ Gyr. Combining our results with published constraints on the orbital parameters obtained through pulsar timing, we estimate the pulsar mass to be $3.4^{+1.4}_{-1.1}$ M$_{\odot}$. Although the constraint on the pulsar mass is still weak, there is a significant possibility that the pulsar could be more massive than two solar mass.
doi:10.3847/1538-4357/aa7209 fatcat:tw6ppo6kcvh3jc5bcwywibl5fq