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arXiv · astro-ph/0509672

Hot subdwarfs in the Galactic Bulge

Abstract

Recent observations and theories suggest that extreme horizontal branch (EHB) stars and their progeny should be the cause of the UV excess seen in the spectra of many elliptical galaxies. Since the Galactic Bulge is the closest representation of an old, metal-rich spheroid in which we are able to study the EHB scenario in detail, we obtained spectra of bulge EHB star candidates and we confirm their status as hot evolved stars. It is the first time that such stars are unambiguously identified in the Galactic Bulge.

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Giorgia Busso, Sabine Moehler, Manuela Zoccali, Uli Heber, and Sukyoung Yi. 2005-09-22. Hot subdwarfs in the Galactic Bulge. https://doi.org/10.1086/498212

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