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A Survey for EHB Stars in the Galactic Bulge

Donald M. Terndrup·Deokkeun An·Angela Hansen·Ruth C. Peterson·Alistair R. Walker·Elaine M. Sadler
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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.

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Donald M. Terndrup, Deokkeun An, Angela Hansen, Ruth C. Peterson, Alistair R. Walker, Elaine M. Sadler. 2003-09-25. A Survey for EHB Stars in the Galactic Bulge. https://doi.org/10.1023/b%3Aastr.0000044328.04425.c1

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