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The angular diameter of R Doradus: a nearby Mira-like star

T. R. Bedding·A. A. Zijlstra·O. von der Luhe·J. G. Robertson·R. G. Marson·J. R. Barton·B. S. Carter
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Abstract

We find the angular diameter of R Doradus to be 57 +/- 5 mas, exceeding that of Betelgeuse and implying that R Dor is larger in apparent size than every star except the Sun. R Dor is shown to be closely related to the Mira variables. We estimate an effective temperature of 2740 +/- 190 K, a distance of 61 +/- 7 pc, a luminosity of 6500 +/- 1400 Lsol and a radius of 370 +/- 50 Rsol. The characteristics of R Dor are consistent with it being near the edge of a Mira instability strip. We detect non-zero closure phases from R Dor, indicating an asymmetric brightness distribution. We also observed W Hya, a small-amplitude Mira, for which we find an angular diameter of 44 +/- 4 mas.

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T. R. Bedding, A. A. Zijlstra, O. von der Luhe, J. G. Robertson, R. G. Marson, J. R. Barton, B. S. Carter. 1997-01-07. The angular diameter of R Doradus: a nearby Mira-like star. https://doi.org/10.1093/mnras%2F286.4.957

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