Timing models for the long orbital period binary pulsar PSR B1259–63 |
| |
| Authors: | N Wex S Johnston R N Manchester A G Lyne B W Stappers & M Bailes |
| |
| Institution: | Max-Planck Society, Research Unit 'Theory of Gravitation', Max-Wien-Pl. 1, D-07743 Jena, Germany,;Research Centre for Theoretical Astrophysics, University of Sydney, NSW 2006, Australia,;Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany,;Australia Telescope National Facility, CSIRO, PO Box 76, Epping, NSW 2121, Australia,;University of Manchester, NRAL, Jodrell Bank, Macclesfield, Cheshire SK11 9DL,;Mount Stromolo and Siding Spring Observatories, ANU, Private Bag, Weston Creek, ACT 2611, Australia,;University of Melbourne, School of Physics, Parkville, Victoria 3052, Australia |
| |
| Abstract: | The pulsar PSR B1259–63 is in a highly eccentric 3.4-yr orbit with the Be star SS 2883. Timing observations of this pulsar, made over a 7-yr period using the Parkes 64-m radio telescope, cover two periastron passages, in 1990 August and 1994 January. The timing data cannot be fitted by the normal pulsar and Keplerian binary parameters. A timing solution including a (non-precessing) Keplerian orbit and timing noise (represented as a polynomial of fifth order in time) provides a satisfactory fit to the data. However, because the Be star probably has a significant quadrupole moment, we prefer to interpret the data by a combination of timing noise, dominated by a cubic phase term, and ω. and x . terms. We show that the ω. and x . terms are likely to be a result of a precessing orbit caused by the quadrupole moment of the tilted companion star. We further rule out a number of possible physical effects which could contribute to the timing data of PSR B1259–63 on a measurable level. |
| |
| Keywords: | binaries: general pulsars: general pulsars: individual: PSR B1259–63 |
|
|
