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Stellar Populations in the Galactic Center

  • G. Bono
  • N. Matsunaga
  • L. Inno
  • E. P. Lagioia
  • K. Genovali
Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP, volume 34)

Abstract

We discuss the stellar content of the Galactic Center, and in particular, recent estimates of the star formation rate (SFR). We discuss pros and cons of the different stellar tracers and focus our attention on the SFR based on the three classical Cepheids recently discovered in the Galactic Center. We also discuss stellar populations in field and cluster stars and present some preliminary results based on near-infrared photometry of a field centered on the young massive cluster Arches. We also provide a new estimate of the true distance modulus to the Galactic Center and we found 14. 49 ± 0. 02(standard) ± 0.10(systematic) mag (7. 91 ± 0. 08 ± 0. 40 kpc). Current estimate agrees quite well with similar photometric and kinematic distance determinations available in the literature. We also discuss the metallicity gradient of the thin disk and the sharp change in the slope when moving across the edge of the inner disk, the Galactic Bar and the Galactic Center. The difference becomes even more compelling if we take into account that metal abundances are based on young stellar tracers (classical Cepheids, Red Supergiants, Luminous Blue Variables). Finally, we briefly outline the possible mechanisms that might account for current empirical evidence.

Keywords

Stellar Population Star Formation Rate Iron Abundance Outer Disk Galactocentric Distance 
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.

Notes

Acknowledgements

It is a pleasure to thank M. Fabrizio for a detailed and critical reading of an early version of this manuscript. One of us GB thanks ASTROMUNDUS and the Department of Astronomy, University of Belgrade for their warm hospitality. We are indebted to the great patience and the constant support from the editors. This work was partially supported by the PRIN MIUR 2011 (P.I. M. Marconi). We are grateful to Jorgen Melnik for the detailed reading of an early draft of this manuscript, and in particular for drawing to our attention the thorny problems connected with NIR photometric calibration.

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© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • G. Bono
    • 1
    • 2
    • 3
  • N. Matsunaga
    • 4
  • L. Inno
    • 1
  • E. P. Lagioia
    • 1
  • K. Genovali
    • 1
  1. 1.Dipartimento di FisicaUniversita’ di Roma Tor VergataRomaItaly
  2. 2.INAF– Osservatorio Astronomico di RomaMonte Porzio CatoneItaly
  3. 3.European Souther ObservatoryGarching bei MünchenGermany
  4. 4.Department of Astronomy, School of ScienceThe University of TokyoTokyoJapan

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