Hostname: page-component-848d4c4894-pjpqr Total loading time: 0 Render date: 2024-06-20T09:13:48.711Z Has data issue: false hasContentIssue false

The 3D Structure of the Galactic Bulge from the MACHO Red Clump Stars

Published online by Cambridge University Press:  13 May 2016

R. Fux
Affiliation:
Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Canberra ACT 2611, Australia
T. Axelrod
Affiliation:
Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Canberra ACT 2611, Australia
P. Popowski
Affiliation:
Lawrence Livermore National Laboratory, CA 94551, USA

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Many evidences demonstrate that the Milky Way is a barred galaxy with the near end of the bar pointing in the first Galactic quadrant (e.g. Gerhard 1999 for a review), thus offering an exceptional chance to study the detailed three-dimensional structure and dynamics of a real bar. One of the best tracer of the Galactic bulge/bar are the red clump stars: they are very numerous, sufficiently bright to be detected throughout the bulge, and their absolute I-magnitude has an intrinsic dispersion of only 0.2 magnitude, with a mean value almost independent of colour and metallicity (Paczyński & Stanek 1998, Udalski 2000). Here we outline an ongoing project aiming to recover the 3D bulge stellar distribution as primarily traced by these stars, as in Stanek et al. (1997), but in a non-parametric way and from the VR database of the MACHO experiment within an almost fully observed ∼ 8° × 8° bulge area centred on (l, b) ≈ (4°, − 6°) (e.g. Alcock et al. 1997), soon complemented with I-band photometry.

Type
The Inner Regions of Galaxies
Copyright
Copyright © Astronomical Society of the Pacific 2001 

References

Alcock, C., Allsman, R.A., Alves, D. et al. 1997, ApJ 479, 119.Google Scholar
Binney, J., Merrifield, M. 1998. Galactic Astronomy, Princeton University Press.Google Scholar
Fux, R. 1999, A&A 345, 787.Google Scholar
Gerhard, O.E. 1999. In: Merritt, D., Sellwood, J.A., Valluri, M. (eds.) Galaxy Dynamics. ASP Conf. Series 182, 307.Google Scholar
Paczyński, B., Stanek, K.Z. 1998, ApJ 494, L219.Google Scholar
Stanek, K.Z., Udalski, A., Szymański, M. et al. 1997, ApJ 477, 163.Google Scholar
Udalski, A. 2000, ApJ 531, L25.Google Scholar
Woźniak, P.R., Stanek, K.Z. 1996, ApJ 464, 233.Google Scholar