The Parkes Multibeam Pulsar Survey - V. Finding binary and millisecond pulsars

The Parkes Multibeam Pulsar Survey is the most successful survey of the Galactic plane ever performed, finding over 600 pulsars in the initial processing. We report on a reprocessing of all 40 000 beams with a number of algorithms, including conventional frequency-domain searches and an acceleration search for fast binary pulsars. The very large volume of results coupled with the need to distinguish new candidates from known pulsars and their many harmonics, often with multiple detections from different search algorithms, necessitated the development of a new graphical selection tool tightly linked to a web-based results data base. We discuss and demonstrate the benefits of these software systems, which are specifically designed for large survey projects. The results of this processing have been encouraging. We have discovered 128 new pulsars, including 11 binary and 15 millisecond pulsars; in addition to those previously found in the survey, we have thus far discovered 737 pulsars. In this paper, we discuss the discoveries of PSR J1744-3922 (a 172-ms mildly recycled pulsar in a 4.6-h orbit that exhibits nulling behaviour, not previously observed in recycled or binary objects), PSR J1802-2124 (an intermediate mass binary pulsar) and PSR J1801-1417 (a solitary millisecond pulsar).