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Young stars in the Galactic Centre: a potential intermediate-mass star origin

Dray, L. M. ; King, A. R. and Davies, Melvyn B LU (2006) In Monthly Notices of the Royal Astronomical Society 372(1). p.31-44
Abstract
There has been recent speculation that the cores of intermediate-mass stars stripped of their envelopes by tidal interaction with the supermassive black hole in the Galactic Centre could form a population observationally similar to the so-called Sgr A* cluster or 'S' stars, which have close eccentric orbits around the hole. We model the evolution of such stars, and show that the more luminous end of the population may indeed appear similar to young B stars within the observational limits of the Galactic Centre region. Whether some or all of these cluster stars can be accounted for in this manner depends strongly on the assumed initial mass function (IMF) of the loss cone stars and the scattering rate. If most of the observed stars are in... (More)
There has been recent speculation that the cores of intermediate-mass stars stripped of their envelopes by tidal interaction with the supermassive black hole in the Galactic Centre could form a population observationally similar to the so-called Sgr A* cluster or 'S' stars, which have close eccentric orbits around the hole. We model the evolution of such stars, and show that the more luminous end of the population may indeed appear similar to young B stars within the observational limits of the Galactic Centre region. Whether some or all of these cluster stars can be accounted for in this manner depends strongly on the assumed initial mass function (IMF) of the loss cone stars and the scattering rate. If most of the observed stars are in fact scattered from the Galactic Centre inner cusp region itself then the population of similar to 20 to current observational limits may be reproduced. However, this only works if the local relaxation time is small and relies on the cusp stars themselves being young, i.e. it is dependent on some star formation being possible in the central few parsecs. Conversely, we obtain a possible constraint on the tidal stripping rate of 'normal' IMF stars if there are not to be red stars visible in the Sgr A* cluster. (Less)
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author
; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Galaxy : centre, stars : early-type, stars : kinematics, Galaxy :, stellar content
in
Monthly Notices of the Royal Astronomical Society
volume
372
issue
1
pages
31 - 44
publisher
Oxford University Press
external identifiers
  • wos:000240823800003
  • scopus:33749181551
ISSN
1365-2966
DOI
10.1111/j.1365-2966.2006.10841.x
language
English
LU publication?
yes
id
d136e024-dc27-4e8b-b5e1-ff39da0385a6 (old id 392629)
date added to LUP
2016-04-01 12:14:25
date last changed
2020-11-22 07:23:52
@article{d136e024-dc27-4e8b-b5e1-ff39da0385a6,
  abstract     = {There has been recent speculation that the cores of intermediate-mass stars stripped of their envelopes by tidal interaction with the supermassive black hole in the Galactic Centre could form a population observationally similar to the so-called Sgr A* cluster or 'S' stars, which have close eccentric orbits around the hole. We model the evolution of such stars, and show that the more luminous end of the population may indeed appear similar to young B stars within the observational limits of the Galactic Centre region. Whether some or all of these cluster stars can be accounted for in this manner depends strongly on the assumed initial mass function (IMF) of the loss cone stars and the scattering rate. If most of the observed stars are in fact scattered from the Galactic Centre inner cusp region itself then the population of similar to 20 to current observational limits may be reproduced. However, this only works if the local relaxation time is small and relies on the cusp stars themselves being young, i.e. it is dependent on some star formation being possible in the central few parsecs. Conversely, we obtain a possible constraint on the tidal stripping rate of 'normal' IMF stars if there are not to be red stars visible in the Sgr A* cluster.},
  author       = {Dray, L. M. and King, A. R. and Davies, Melvyn B},
  issn         = {1365-2966},
  language     = {eng},
  number       = {1},
  pages        = {31--44},
  publisher    = {Oxford University Press},
  series       = {Monthly Notices of the Royal Astronomical Society},
  title        = {Young stars in the Galactic Centre: a potential intermediate-mass star origin},
  url          = {http://dx.doi.org/10.1111/j.1365-2966.2006.10841.x},
  doi          = {10.1111/j.1365-2966.2006.10841.x},
  volume       = {372},
  year         = {2006},
}