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A source of high-velocity white dwarfs

Davies, Melvyn B LU ; King, A. and Ritter, H. (2002) In Monthly Notices of the Royal Astronomical Society 333. p.463-468
Abstract
We investigate whether the recently observed population of high-velocity white dwarfs can be derived from a population of binaries residing initially within the thin disc of the Galaxy. In particular, we consider binaries where the primary is sufficiently massive to explode as a Type II supernova. A large fraction of such binaries are broken up when the primary then explodes as a supernova, owing to the combined effects of the mass loss from the primary and the kick received by the neutron star on its formation. For binaries where the primary evolves to fill its Roche lobe, mass transfer from the primary leads to the onset of a common envelope phase during which the secondary and the core of the primary spiral together as the envelope is... (More)
We investigate whether the recently observed population of high-velocity white dwarfs can be derived from a population of binaries residing initially within the thin disc of the Galaxy. In particular, we consider binaries where the primary is sufficiently massive to explode as a Type II supernova. A large fraction of such binaries are broken up when the primary then explodes as a supernova, owing to the combined effects of the mass loss from the primary and the kick received by the neutron star on its formation. For binaries where the primary evolves to fill its Roche lobe, mass transfer from the primary leads to the onset of a common envelope phase during which the secondary and the core of the primary spiral together as the envelope is ejected. Such binaries are the progenitors of X-ray binaries if they are not broken up when the primary explodes. For those systems that are broken up, a large number of the secondaries receive kick velocities ~100-200kms-1 and subsequently evolve into white dwarfs. We compute trajectories within the Galactic potential for this population of stars and relate the birth rate of these stars over the entire Galaxy to those seen locally with high velocities relative to the local standard of rest (LSR). We show that for a reasonable set of assumptions concerning the Galactic supernova rate and the binary population, our model produces a local number density of high-velocity white dwarfs compatible with that inferred from observations. We therefore propose that a population of white dwarfs originating in the thin disc may make a significant contribution to the observed population of high-velocity white dwarfs. (Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Contribution to journal
publication status
published
subject
keywords
accretion discs, accretion, binaries: close, stars: general, white dwarfs, stars: evolution
in
Monthly Notices of the Royal Astronomical Society
volume
333
pages
463 - 468
publisher
Wiley-Blackwell
external identifiers
  • Scopus:0012429439
ISSN
1365-2966
language
English
LU publication?
no
id
5fe8656b-5090-49fd-8704-244c0a62f8b8 (old id 761234)
alternative location
http://cdsads.u-strasbg.fr/abs/2002MNRAS.333..463D
date added to LUP
2007-12-17 13:43:10
date last changed
2016-10-13 04:47:19
@misc{5fe8656b-5090-49fd-8704-244c0a62f8b8,
  abstract     = {We investigate whether the recently observed population of high-velocity white dwarfs can be derived from a population of binaries residing initially within the thin disc of the Galaxy. In particular, we consider binaries where the primary is sufficiently massive to explode as a Type II supernova. A large fraction of such binaries are broken up when the primary then explodes as a supernova, owing to the combined effects of the mass loss from the primary and the kick received by the neutron star on its formation. For binaries where the primary evolves to fill its Roche lobe, mass transfer from the primary leads to the onset of a common envelope phase during which the secondary and the core of the primary spiral together as the envelope is ejected. Such binaries are the progenitors of X-ray binaries if they are not broken up when the primary explodes. For those systems that are broken up, a large number of the secondaries receive kick velocities ~100-200kms-1 and subsequently evolve into white dwarfs. We compute trajectories within the Galactic potential for this population of stars and relate the birth rate of these stars over the entire Galaxy to those seen locally with high velocities relative to the local standard of rest (LSR). We show that for a reasonable set of assumptions concerning the Galactic supernova rate and the binary population, our model produces a local number density of high-velocity white dwarfs compatible with that inferred from observations. We therefore propose that a population of white dwarfs originating in the thin disc may make a significant contribution to the observed population of high-velocity white dwarfs.},
  author       = {Davies, Melvyn B and King, A. and Ritter, H.},
  issn         = {1365-2966},
  keyword      = {accretion discs,accretion,binaries: close,stars: general,white dwarfs,stars: evolution},
  language     = {eng},
  pages        = {463--468},
  publisher    = {ARRAY(0x9722c88)},
  series       = {Monthly Notices of the Royal Astronomical Society},
  title        = {A source of high-velocity white dwarfs},
  volume       = {333},
  year         = {2002},
}