Arecibo PALFA Survey and Einstein@Home: Binary Pulsar Discovery by
  Volunteer Computing
  We report the discovery of the 20.7 ms binary pulsar J1952+2630, made using
the distributed computing project Einstein@Home in Pulsar ALFA survey
observations with the Arecibo telescope. Follow-up observations with the
Arecibo telescope confirm the binary nature of the system. We obtain a circular
orbital solution with an orbital period of 9.4 hr, a projected orbital radius
of 2.8 lt-s, and a mass function of f = 0.15 solar masses by analysis of spin
period measurements. No evidence of orbital eccentricity is apparent; we set a
2-sigma upper limit e < 1.7e-3. The orbital parameters suggest a massive white
dwarf companion with a minimum mass of 0.95 solar masses, assuming a pulsar
mass of 1.4 solar masses. Most likely, this pulsar belongs to the rare class of
intermediate mass binary pulsars. Future timing observations will aim to
determine the parameters of this system further, measure relativistic effects,
and elucidate the nature of the companion star.
