A Survey for EHB Stars in the Galactic Bulge

Abstract

We present a progress report on an extensive survey to find and characterize all types of blue horizontal-branch stars in the nuclear bulge of the Galaxy. We have obtained wide, shallow imaging in UBV of ~12 square degrees in the bulge, with follow-up spectroscopy for radial velocities and metal abundance determinations. We have discovered a number of metal-rich blue HB stars, whose presence in the bulge is expected by the interpretation of the extragalactic ultraviolet excess. Very deep images have been obtained in UBV and SDSS u along the bulge minor axis, which reveal a significant number of EHB candidates fainter than B = 19, i.e., with the same absolute magnitudes as EHB stars in several globular clusters.

arXiv commentTo appear in "Extreme Horizontal Branch Stars and Related Objects", Astrophysics and Space Science, Kluwer Academic Publishers, proceedings of the meeting held in Keele, UK, June 16-20, 2003

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Cited by in corpus (4)

• Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy
• Milky Way demographics with the VVV survey. IV. PSF photometry from almost one billion stars in the Galactic bulge and adjacent southern disk
• Hot subdwarfs in the Galactic Bulge
• VVV Survey of Blue Horizontal-Branch Stars in the Bulge-Halo Transition Region of the Milky Way