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arXiv · 0809.0568

The Extragalactic Distance Scale without Cepheids

Jeremy Mould·Shoko Sakai
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Abstract

Distances of galaxies in the Hubble Space Telescope Key Project are based on the Cepheid period-luminosity relation. An alternative basis is the tip of the red giant branch. Using archival HST data, we calibrate the infrared Tully-Fisher relation using 14 galaxies with tip of the red giant branch measurements. Compared with the Key Project, a higher value of the Hubble Constant by 10% +/- 7% is inferred. Within the errors the two distance scales are therefore consistent. We describe the additional data required for a conclusive tip of the red giant branch measurement of H_0.

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Jeremy Mould, Shoko Sakai. 2008-09-03. The Extragalactic Distance Scale without Cepheids. https://doi.org/10.1088/0004-637x%2F697%2F2%2F996

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