SDSS spectroscopic survey of stars
/ Authors
Ž. Ivezić, D. Schlegel, A. Uomoto, N. Bond, T. Beers, C. Prieto, R. Wilhelm, Y. Lee, T. Sivarani, M. Jurić
and 31 more authors
R. Lupton, C. Rockosi, G. Knapp, J. Gunn, B. Yanny, S. Jester, S. Kent, J. Pier, J. Munn, G. Richards, H. Newberg, M. Blanton, D. Eisenstein, S. Hawley, S. Anderson, H. Harris, F. Kiuchi, A. Chen, J. Bushong, H. Sohi, D. Haggard, A. Kimball, J. Barentine, H. Brewington, M. Harvanek, S. Kleinman, J. Krzesinski, D. Long, A. Nitta, S. Snedden, F. C. Collaboration
/ Abstract
In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is also producing a massive spectroscopic database. They discuss determination of stellar parameters, such as effective temperature, gravity and metallicity from SDSS spectra, describe correlations between kinematics and metallicity, and study their variation as a function of the position in the Galaxy. They show that stellar parameter estimates by Beers et al. show a good correlation with the position of a star in the g-r vs. u-g color-color diagram, thereby demonstrating their robustness as well as a potential for photometric parameter estimation methods. Using Beers et al. parameters, they find that the metallicity distribution of the Milky Way stars at a few kpc from the galactic plane is bimodal with a local minimum at [Z/Z{sub {circle_dot}}] {approx} -1.3. The median metallicity for the low-metallicity [Z/Z{sub {circle_dot}}] -1.3 sample. they also find that the low-metallicity sample has {approx} 2.5 times larger velocity dispersion and that it does not rotate (at the {approx} 10 km/s level), while the rotational velocity of the high-metallicity samplemore » decreases smoothly with the height above the galactic plane.« less