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New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s) Improved astrophysical parameters for the Geneva-Copenhagen Survey

Casagrande, L.; Schoenrich, R.; Asplund, M.; Cassisi, S.; Ramirez, I.; Melendez, J.; Bensby, Thomas LU and Feltzing, Sofia LU (2011) In Astronomy & Astrophysics 530.
Abstract
We present a re-analysis of the Geneva-Copenhagen survey, which benefits from the infrared flux method to improve the accuracy of the derived stellar effective temperatures and uses the latter to build a consistent and improved metallicity scale. Metallicities are calibrated on high-resolution spectroscopy and checked against four open clusters and a moving group, showing excellent consistency. The new temperature and metallicity scales provide a better match to theoretical isochrones, which are used for a Bayesian analysis of stellar ages. With respect to previous analyses, our stars are on average 100 K hotter and 0.1 dex more metal rich, which shift the peak of the metallicity distribution function around the solar value. From Stromgren... (More)
We present a re-analysis of the Geneva-Copenhagen survey, which benefits from the infrared flux method to improve the accuracy of the derived stellar effective temperatures and uses the latter to build a consistent and improved metallicity scale. Metallicities are calibrated on high-resolution spectroscopy and checked against four open clusters and a moving group, showing excellent consistency. The new temperature and metallicity scales provide a better match to theoretical isochrones, which are used for a Bayesian analysis of stellar ages. With respect to previous analyses, our stars are on average 100 K hotter and 0.1 dex more metal rich, which shift the peak of the metallicity distribution function around the solar value. From Stromgren photometry we are able to derive for the first time a proxy for [alpha/Fe] abundances, which enables us to perform a tentative dissection of the chemical thin and thick disc. We find evidence for the latter being composed of an old, mildly but systematically alpha-enhanced population that extends to super solar metallicities, in agreement with spectroscopic studies. Our revision offers the largest existing kinematically unbiased sample of the solar neighbourhood that contains full information on kinematics, metallicities, and ages and thus provides better constraints on the physical processes relevant in the build-up of the Milky Way disc, enabling a better understanding of the Sun in a Galactic context. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
stars: abundances, stars: fundamental parameters, Hertzsprung-Russell, and C-M diagrams, stars: kinematics and dynamics, Galaxy: disk, solar, neighborhood
in
Astronomy & Astrophysics
volume
530
publisher
EDP Sciences
external identifiers
  • wos:000291027400138
  • scopus:79957614217
ISSN
0004-6361
DOI
10.1051/0004-6361/201016276
language
English
LU publication?
yes
id
2a12e1a3-e495-4b3e-97e0-3f622525316c (old id 1986149)
date added to LUP
2011-06-29 15:43:40
date last changed
2017-11-12 03:46:27
@article{2a12e1a3-e495-4b3e-97e0-3f622525316c,
  abstract     = {We present a re-analysis of the Geneva-Copenhagen survey, which benefits from the infrared flux method to improve the accuracy of the derived stellar effective temperatures and uses the latter to build a consistent and improved metallicity scale. Metallicities are calibrated on high-resolution spectroscopy and checked against four open clusters and a moving group, showing excellent consistency. The new temperature and metallicity scales provide a better match to theoretical isochrones, which are used for a Bayesian analysis of stellar ages. With respect to previous analyses, our stars are on average 100 K hotter and 0.1 dex more metal rich, which shift the peak of the metallicity distribution function around the solar value. From Stromgren photometry we are able to derive for the first time a proxy for [alpha/Fe] abundances, which enables us to perform a tentative dissection of the chemical thin and thick disc. We find evidence for the latter being composed of an old, mildly but systematically alpha-enhanced population that extends to super solar metallicities, in agreement with spectroscopic studies. Our revision offers the largest existing kinematically unbiased sample of the solar neighbourhood that contains full information on kinematics, metallicities, and ages and thus provides better constraints on the physical processes relevant in the build-up of the Milky Way disc, enabling a better understanding of the Sun in a Galactic context.},
  author       = {Casagrande, L. and Schoenrich, R. and Asplund, M. and Cassisi, S. and Ramirez, I. and Melendez, J. and Bensby, Thomas and Feltzing, Sofia},
  issn         = {0004-6361},
  keyword      = {stars: abundances,stars: fundamental parameters,Hertzsprung-Russell,and C-M diagrams,stars: kinematics and dynamics,Galaxy: disk,solar,neighborhood},
  language     = {eng},
  publisher    = {EDP Sciences},
  series       = {Astronomy & Astrophysics},
  title        = {New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s) Improved astrophysical parameters for the Geneva-Copenhagen Survey},
  url          = {http://dx.doi.org/10.1051/0004-6361/201016276},
  volume       = {530},
  year         = {2011},
}