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STELLAR POPULATIONS IN BULGES OF SPIRAL GALAXIES

  • Bhaskeand K. Moorthy
  • Jon A. Holtzman
Part of the Astrophysics and Space Science Proceedings book series (ASSSP)

Abstract

To better understand bulge formation, we have used long-slit spectroscopy and imaging to obtain luminosity-weighted (SSP) ages and abundances, line of sight velocity distributions, and bulge-to-disk decomposition for 38 spiral galaxies. We specifically included several blue bulges to see if these show evidence for secular evolution. Here we describe the stellar populations and how they relate to the kinematics and dynamics. We find that red bulges are similar to luminous ellipticals in their central line strengths, with large SSP ages and super-solar metallicities and α/Fe ratios. Blue bulges are similar to low-luminosity ellipti-cals in their central line strengths. They have solar α/Fe ratios and either small age or small metallicity. The colors, metallicities, and α/Fe ratios of bulges are correlated with the central velocity dispersion and maximum disk rotational velocity. Most bulges have metallicity gradients, but the metallicities of the bulge and disk are correlated. These observations suggest that the star-formation histories of ellipticals, bulges, and disks are sensitive primarily to the depth of the galactic potential well, but the scatter in the scaling relations leaves room for multiple formation mechanisms.

Keywords

Spiral Galaxy Stellar Population Secular Evolution Maximum Disk Lenticular Galaxy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Caldwell, N., Rose, J. A., & Concannon, K. D. 2003, AJ, 125, 2891CrossRefADSGoogle Scholar
  2. Cappellari, M., & Emsellem, E. 2004, PASP, 116, 138CrossRefADSGoogle Scholar
  3. Carollo, C. M., Stiavelli, M., de Zeeuw, P. T., & Mack, J. 1997, AJ 114, 2366CrossRefADSGoogle Scholar
  4. Cole, S., Aragón-Salamanca, A., Frenk, C. S., Navarro, J. F., & Zepf, S. E. 1994, MNRAS, 271, 781ADSGoogle Scholar
  5. Courteau, S., de Jong, R. S., & Broeils, A. H. 1996, ApJ, 457, L73CrossRefADSGoogle Scholar
  6. de Jong, R. S. 1996, A&A, 313, 377ADSGoogle Scholar
  7. Denicoló, G. Terlevich, R., Terlevich, E., Forbes, D. A., Terlevich, A. & Carrasco, L. 2005, MNRAS, 356, 1440CrossRefADSGoogle Scholar
  8. Falcón-Barroso, J., Peletier, R. F, & Balcells, M. 2002, MNRAS, 335, 741CrossRefADSGoogle Scholar
  9. Kormendy, J., & Kennicutt, R. C. 2004, ARA&A, 42, 603ADSCrossRefGoogle Scholar
  10. Kormendy, J., & Illingworth, G. 1982, ApJ, 256, 460CrossRefADSGoogle Scholar
  11. MacArthur, L. A., Courteau, S., Bell, E. F., Holtzman, J. A. 2004, ApJS 152, 175CrossRefADSGoogle Scholar
  12. MacArthur, L. A., Courteau, S., & Holtzman, J. A. 2003, ApJ, 582, 689CrossRefADSGoogle Scholar
  13. Peletier, R. F, & Balcells, M. 1997, New Astronomy, 1, 349CrossRefADSGoogle Scholar
  14. Peletier, R. F, & Balcells, M. 1996, AJ, 111, 2238CrossRefADSGoogle Scholar
  15. Proctor, R. N., & Sansom, A. E. 2002, MNRAS, 333,517CrossRefADSGoogle Scholar
  16. Prugniel, P., Maubon, G. & Simien, F. 2001, A&A, 366, 68CrossRefADSGoogle Scholar
  17. Puzia, T. H., Perrett, K. M., & Bridges, T. J. 2005, A&A, 434, 909CrossRefADSGoogle Scholar
  18. Puzia, T. H., Saglia, R. P., Kissler-Patig, M., Maraston, C., Greggio, L., Renzini, A., & Ortolani, S. 2002, A&A, 395, 45CrossRefADSGoogle Scholar
  19. Thomas, D., Maraston, C., Bender, R., & de Oliveira, C. M. 2005, ApJ, 621, 673CrossRefADSGoogle Scholar
  20. Thomas, D., Maraston, C., & Bender, R. (TMB) 2003, MNRAS, 339, 897CrossRefADSGoogle Scholar
  21. Trager, S. C., Faber, S. M., Worthey, G., & González, J. J. 2000b, AJ, 120, 165CrossRefADSGoogle Scholar
  22. Trager, S. C., Worthey, G., Faber, S. M., Burstein, D., & González, J. J. 1998, ApJS, 116, 1CrossRefADSGoogle Scholar
  23. Worthey, G. 1994, ApJS, 95, 107CrossRefADSGoogle Scholar
  24. Worthey, G., & Ottaviani, D. L. 1997, ApJS, 111, 377CrossRefADSGoogle Scholar

Copyright information

© Springer 2007

Authors and Affiliations

  • Bhaskeand K. Moorthy
    • 1
  • Jon A. Holtzman
    • 1
  1. 1.Department of AstronomyNew Mexico State UniversityLas CrucesUSA

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