Improving Binary Millisecond Pulsar Distances with Gaia

Improved distance measurements to millisecond pulsars can enhance pulsar timing array (PTA) sensitivity to gravitational-waves, improve tests of general relativity with binary pulsars, improve constraints on fuzzy dark matter, and more. Here we report the parallax and distance measurements to seven Gaia DR2 objects associated with seven International PTA pulsars: J0437-4715, J1012+5307, J1024-0719, J1732-5049, J1910+1256, J1843-1113, and J1949+3106. By multiplying the posteriors of the PTA-based parallax measurements with the Gaia parallax measurement to the pulsar's companion, we improve the distance measurements from a few percent to a factor of five, and a tentative detection of a binary companion to J1843-1113. We also find an order of magnitude improvement in the parallax measurement to J1949+3106.