Local stellar kinematics from RAVE data - II. Radial metallicity gradient

Coskunoglu B., Ak S., Bilir S., Karaali S., Onal Ö., Yaz E., ...More

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, vol.419, pp.2844-2854, 2012 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 419
  • Publication Date: 2012
  • Doi Number: 10.1111/j.1365-2966.2011.19925.x
  • Journal Name: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2844-2854
  • Keywords: stars: abundances, Galaxy: abundances, Galaxy: disc, Galaxy: evolution, VELOCITY EXPERIMENT RAVE, ELEMENTAL ABUNDANCE RATIOS, OUTER GALACTIC DISK, FIELD STAR SURVEY, MILKY-WAY, SOLAR NEIGHBORHOOD, DATA RELEASE, CHEMICAL EVOLUTION, SPACE VELOCITIES, THICK DISKS
  • Istanbul University Affiliated: Yes

Abstract

We investigate radial metallicity gradients for a sample of dwarf stars from the RAdial Velocity Experiment (RAVE) Data Release 3 (DR3). We select a total of approximately 17 000 F-type and G-type dwarfs, using a selection of colour, log g and uncertainty in the derived space motion, and calculate for each star a probabilistic (kinematic) population assignment to a thick or thin disc using space motion and additionally another (dynamical) assignment using stellar vertical orbital eccentricity. We additionally subsample by colour, to provide samples biased toward young thin-disc and older thin-disc stars. We derive a metallicity gradient as a function of Galactocentric radial distance, i.e. d[M/H]/dRm=-0.051 +/- 0.005 dex kpc-1, for the youngest sample, F-type stars with vertical orbital eccentricities e(v) <= 0.04. Samples biased toward older thin-disc stars show systematically shallower abundance gradients.