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Resolving the 47 Tucanae Distance Problem

Susan M. Percival·Maurizio Salaris·Francois van Wyk·David Kilkenny
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Abstract

Using a sample of 43 suitable local subdwarfs with newly acquired BVI photometry, we apply our main sequence fitting method to the metal rich Globular Cluster 47 Tucanae. Fitting in 2 colour planes, we find an apparent distance modulus of (m-M)v = 13.37 (+0.10/-0.11), leading to a dereddened distance modulus of (m-M)o = 13.25 (+0.06/-0.07). Consideration of the Red Clump in the cluster produces a distance modulus fully consistent with this result. The implied cluster age is 11 (+/-1.4) Gyr.

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Susan M. Percival, Maurizio Salaris, Francois van Wyk, David Kilkenny. 2002-09-04. Resolving the 47 Tucanae Distance Problem. https://arxiv.org/abs/astro-ph/0209074

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