Advertisement

Astronomy Reports

, Volume 47, Issue 2, pp 88–98 | Cite as

The chemically distinct nucleus and structure of the S0 galaxy NGC 80

  • O. K. Sil’chenko
  • S. E. Koposov
  • V. V. Vlasyuk
  • O. I. Spiridonova
Article

Abstract

The giant lenticular galaxy NGC 80, which is the brightest member of a rich group, possesses a central evolutionarily-distinct region: the stars in the nucleus and in a circumnuclear ring of radius 5″t–7″ have a mean age of only 7 Gyr, whereas the stellar population of the bulge is older than 10 Gyr. The nucleus of NGC 80 is also chemically distinct: it is a factor of 2–2.5 richer in metals than its immediate neighborhood and is characterized by a high magnesium-to-iron abundance ratio [Mg/Fe]≈+0.3. The global stellar disk of NGC 80 has a two-tiered structure: its outer part has an exponential scale length of 11 kpc and normal surface density, while the inner disk, which is also exponential and axisymmetric, is more compact and brighter. Although the two-tiered structure and the chemically distinct nucleus obviously have a common origin and owe their existence to some catastrophic restructuring of the protogalactic gaseous disk, the origin of this remains unclear, since the galaxy lacks any manifestations of perturbed morphology or triaxiality.

Keywords

Surface Density Outer Part Common Origin Abundance Ratio Stellar Population 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    D. Maoz, A. V. Filippenko, L. C. Ho, et al., Astrophys. J., Suppl. Ser. 107, 215 (1996).CrossRefADSGoogle Scholar
  2. 2.
    P. T. de Zeeuw, M. Bureau, E. Emsellem, et al., Mon. Not. R. Astron. Soc. 329, 513 (2002).ADSGoogle Scholar
  3. 3.
    R. Buta, Publ. Astron. Soc. Pac. 105, 654 (1993).CrossRefADSGoogle Scholar
  4. 4.
    R. Buta and D. A. Crocker, Astron. J. 105, 1344 (1993).CrossRefADSGoogle Scholar
  5. 5.
    R. Buta, W. van Driel, J. Braine, et al., Astrophys. J. 450, 593 (1995).CrossRefADSGoogle Scholar
  6. 6.
    R. Buta, Astrophys. J. 370, 130 (1991).CrossRefADSGoogle Scholar
  7. 7.
    L. Athanassoula, Barred Galaxies, Ed. by R. Buta, D. A. Crocker, and B. G. Elmegreen, Astron. Soc. Pac. Conf. Ser. 91, 309 (1996).Google Scholar
  8. 8.
    O. K. Sil’chenko, Astron. Astrophys. Trans. 20, 123 (2001).Google Scholar
  9. 9.
    O. K. Sil’chenko, Astron. J. 117, 2725 (1999).ADSGoogle Scholar
  10. 10.
    O. K. Sil’chenko, Astron. J. 118, 186 (1999).ADSGoogle Scholar
  11. 11.
    V. V. Vlasyuk and O. K. Sil’chenko, Astron. Astrophys. 354, 28 (2000).ADSGoogle Scholar
  12. 12.
    T. Wiklind, F. Combes, C. Henkel, and F. Wyrowski, Astron. Astrophys. 323, 727 (1997).ADSGoogle Scholar
  13. 13.
    O. K. Sil’chenko, Astron. Zh. 71, 706 (1994) [Astron. Rep. 38, 624 (1994)].ADSGoogle Scholar
  14. 14.
    R. Buta and K. L. Williams, Astron. J. 109, 543 (1995).ADSGoogle Scholar
  15. 15.
    P. Chamaraux, C. Balkowski, and P. Fontanelli, Astron. Astrophys. 165, 15 (1986).ADSGoogle Scholar
  16. 16.
    P. Prugniel and F. Simien, Astron. Astrophys. 282, L1 (1994).ADSGoogle Scholar
  17. 17.
    V. L. Afanas’ev, V. V. Vlasyuk, S. N. Dodonov, and O. K. Sil’chenko, Preprint No. 54, SAO AN SSSR (1990).Google Scholar
  18. 18.
    V. V. Vlasyuk, Astrofiz. Issled. (Izv. SAO RAN) 36, 107 (1993).Google Scholar
  19. 19.
    G. Worthey, S. M. Faber, J. J. González, and D. Burstein, Astrophys. J., Suppl. Ser. 94, 687 (1994).CrossRefADSGoogle Scholar
  20. 20.
    G. Worthey, Astrophys. J., Suppl. Ser. 95, 107 (1994).CrossRefADSGoogle Scholar
  21. 21.
    R. Tantalo, C. Chiosi, and A. Bressan, Astron. Astrophys. 333, 419 (1998).ADSGoogle Scholar
  22. 22.
    P. Poulain, Astron. Astrophys., Suppl. Ser. 72, 215 (1988).ADSGoogle Scholar
  23. 23.
    A. U. Landolt, Astron. J. 104, 340 (1992).ADSGoogle Scholar
  24. 24.
    S. C. Trager, G. Worthey, S. M. Faber, et al., Astrophys. J., Suppl. Ser. 116, 1 (1998).CrossRefADSGoogle Scholar
  25. 25.
    O. K. Sil’chenko, Pis’ma Astron. Zh. 19, 693 (1993) [Astron. Lett. 19, 279 (1993)].ADSGoogle Scholar
  26. 26.
    G. Worthey, S. M. Faber, and J. J. González, Astrophys. J. 398, 69 (1992).CrossRefADSGoogle Scholar
  27. 27.
    O. K. Sil’chenko, in Galaxies: The Third Dimension, Ed. by M. Rosado, L. Binette, and L. Arias (2002) (in press).Google Scholar
  28. 28.
    G. Magrelli, D. Bettoni, and G. Galetta, Mon. Not. R. Astron. Soc. 256, 500 (1992).ADSGoogle Scholar
  29. 29.
    J. Kormendy, Astrophys. J. 217, 406 (1977).CrossRefADSGoogle Scholar
  30. 30.
    W. E. Baggett, S. M. Baggett, and K. S. J. Anderson, Astron. J. 116, 1626 (1998).CrossRefADSGoogle Scholar
  31. 31.
    J. Kormendy, Astrophys. J. 218, 333 (1977).CrossRefADSGoogle Scholar
  32. 32.
    R. S. de Jong, Astron. Astrophys. 313, 45 (1996).ADSGoogle Scholar
  33. 33.
    K. C. Freeman, Astrophys. J. 160, 811 (1970).ADSGoogle Scholar
  34. 34.
    A. Vazdekis, E. Casuso, R. F. Peletier, and J. E. Beckman, Astrophys. J., Suppl. Ser. 106, 307 (1996).CrossRefADSGoogle Scholar
  35. 35.
    O. K. Sil’chenko, V. V. Vlasyuk, and F. Alvarado, Astron. J. 121, 2499 (2001).ADSGoogle Scholar
  36. 36.
    O. K. Sil’chenko and V. L. Afanasiev, Astron. Astrophys. 364, 479 (2000).ADSGoogle Scholar
  37. 37.
    O. K. Sil’chenko and V. L. Afanasiev, Astron. Astrophys. 385, 1 (2002).ADSGoogle Scholar

Copyright information

© MAIK "Nauka/Interperiodica" 2003

Authors and Affiliations

  • O. K. Sil’chenko
    • 1
  • S. E. Koposov
    • 1
  • V. V. Vlasyuk
    • 2
  • O. I. Spiridonova
    • 2
  1. 1.Sternberg Astronomical InstituteMoscowRussia
  2. 2.Special Astrophysical ObservatoryRussian Academy of SciencesKarachai-CherkessiaRussia

Personalised recommendations