Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2010-11-26
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
16 pages in emulate MNRAS format, 11 figures, 2 tables, accepted for publication in MNRAS
Scientific paper
(abridged) PSR J1903+0327, a millisecond pulsar in an eccentric (e = 0.44) 95-day orbit with a (~ 1Msun) 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% confidence limit) (...). Optical spectroscopy of a proposed main sequence counterpart show that its orbital motion mirrors the pulsar's 95-day orbit; being therefore its binary companion (...) 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 3-D 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, the present companion was a tertiary farther out. The neutron star then accreted matter from its evolving inner MS companion, forming a millisecond pulsar. The former donor star then disappears, either due to a chaotic 3-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.
Bassa Cees G.
Camilo Fernando
Champion David J.
Cordes James M.
Deneva Julia S.
No associations
LandOfFree
On the nature and evolution of the unique binary pulsar J1903+0327 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On the nature and evolution of the unique binary pulsar J1903+0327, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the nature and evolution of the unique binary pulsar J1903+0327 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-463038