Journal article
On the nature and evolution of the unique binary pulsar J1903+0327
Monthly notices of the Royal Astronomical Society, Vol.412(4), pp.2763-2780
09/2012
Handle:
https://hdl.handle.net/2376/104397
Abstract
PSR J1903+0327, a millisecond pulsar in an eccentric (e= 0.44) 95-d orbit with an ∼1 M⊙ companion poses a challenge to our understanding of stellar evolution in binary and multiple-star systems. Here we describe optical and radio observations which rule out most of the scenarios proposed to explain formation of this system. Radio timing measurements of three post-Keplerian effects yield the most precise measurement of the mass of a millisecond pulsar to date: 1.667 ± 0.021 solar masses (99.7 per cent confidence limit). This rules out some equations of state for superdense matter; furthermore, it is consistent with the spin-up of the pulsar by mass accretion, as suggested by its short spin period and low magnetic field. Optical spectroscopy of a proposed main-sequence counterpart shows that its orbital motion mirrors the pulsar's 95-d orbit; being therefore its binary companion. This finding rules out a previously suggested scenario which proposes that the system is presently a hierarchical triple. Conventional binary evolution scenarios predict that, after recycling a neutron star into a millisecond pulsar, the binary companion should become a white dwarf and its orbit should be nearly circular. This suggests that if PSR J1903+0327 was recycled, its present companion was not responsible for it. The optical detection also provides a measurement of the systemic radial velocity of the binary; this and the proper motion measured from pulsar timing allow the determination of the systemic 3D velocity in the Galaxy. We find that the system is always within 270 pc of the plane of the Galaxy, but always more than 3 kpc away from the Galactic Centre. Thus an exchange interaction in a dense stellar environment (like a globular cluster or the Galactic Centre) is not likely to be the origin of this system. We suggest that after the supernova that formed it, the neutron star was in a tight orbit with a main-sequence star and the present companion was a tertiary farther out. The neutron star then accreted matter from its evolving inner companion, forming a millisecond pulsar. The inner companion then disappeared, either due to a chaotic three-body interaction with the outer star (caused by the expansion of the inner orbit that necessarily results from mass transfer), or in the case of a very compact inner system, due to ablation/accretion by the newly formed millisecond pulsar. We discuss in detail the possible evolution of such a system before the supernova.
Metrics
10 Record Views
Details
- Title
- On the nature and evolution of the unique binary pulsar J1903+0327
- Creators
- P. C. C Freire - 1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, GermanyC. G Bassa - 2Jodrell Bank Centre for Astrophysics, University of Manchester, Oxford Rd, Manchester M13 9PLN Wex - 1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, GermanyI. H Stairs - 3Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Rd., Vancouver, BC V6T 1Z1, CanadaD. J Champion - 1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, GermanyS. M Ransom - 4National Radio Astronomy Observatory, 520 Edgemont Rd., Charlottesville, VA 22903, USAP Lazarus - 5Department of Physics, McGill University, Montreal, QC H3A 2T8, CanadaV. M Kaspi - 5Department of Physics, McGill University, Montreal, QC H3A 2T8, CanadaJ. W. T Hessels - 6Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo, the NetherlandsM Kramer - 1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, GermanyJ. M Cordes - 8Department of Astronomy, Cornell University, Ithaca, NY 14853, USAJ. P. W Verbiest - 1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, GermanyP Podsiadlowski - 10Department of Astronomy, Oxford University, Oxford OX1 3RHD. J Nice - 11Department of Physics, Lafayette College, Easton, PA 18042, USAJ. S Deneva - 12Arecibo Observatory, HC 3 53995, Arecibo, PR 00612, USAD. R Lorimer - 9Department of Physics, West Virginia University, Hodges Hall, Morgantown, WV 26506-6315, USAB. W Stappers - 2Jodrell Bank Centre for Astrophysics, University of Manchester, Oxford Rd, Manchester M13 9PLM. A McLaughlin - 9Department of Physics, West Virginia University, Hodges Hall, Morgantown, WV 26506-6315, USAF Camilo - 14Columbia Astrophysics Laboratory, Columbia University, 550 West 120th St., New York, NY 10027, USA
- Publication Details
- Monthly notices of the Royal Astronomical Society, Vol.412(4), pp.2763-2780
- Publisher
- Blackwell Publishing Ltd; Oxford, UK
- Identifiers
- 99900546720901842
- Language
- English
- Resource Type
- Journal article