1. SDSS spectroscopic survey of stars
- Author
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Ivezic, Z., Schlegel, D., Uomoto, A., Bond, N., Beers, T., Prieto, C. Allende, Wilhelm, R., Lee, Y. Sun, Sivarani, T., Juric, M., Lupton, R., Rockosi, C., Knapp, G., Gunn, J., Yanny, B., Jester, S., Kent, S., Pier, J., Munn, J., Richards, G., Newberg, H., Blanton, M., Eisenstein, D., Hawley, S., Anderson, S., Harris, H., Kiuchi, F., Chen, A., Bushong, J., Sohi, H., Haggard, D., Kimball, A., Barentine, J., Brewington, H., Harvanek, M., Kleinman, S., Krzesinski, J., Long, D., Nitta, A., and Snedden, S.
- Subjects
Astrophysics - Abstract
In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is also producing a massive spectroscopic database. We 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. We 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, we 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/Zo]~ -1.3. The median metallicity for the low-metallicity [Z/Zo]<-1.3 subsample is nearly independent of Galactic cylindrical coordinates R and z, while it decreases with z for the high-metallicity [Z/Zo]> -1.3 sample. We also find that the low-metallicity sample has ~2.5 times larger velocity dispersion and that it does not rotate (at the ~10 km/s level), while the rotational velocity of the high-metallicity sample decreases smoothly with the height above the galactic plane., Comment: 8 pages, color figures, presented at the IAU Joint Discussion 13: "Exploiting Large Surveys for Galactic Astronomy", Prag, August 22-23, 2006
- Published
- 2007