Details

Autor(en) / Beteiligte

• North, J. R.
• Davis, J.
• Bedding, T. R.
• Ireland, M. J.
• Jacob, A. P.
• O'Byrne, J.
• Owens, S. M.
• Robertson, J. G.
• Tango, W. J.
• Tuthill, P. G.

Titel

The radius and mass of the subgiant star β Hyi from interferometry and asteroseismology

Ist Teil von

• Monthly notices of the Royal Astronomical Society. Letters, 2007-09, Vol.380 (1), p.L80-L83

Ort / Verlag

Oxford, UK: Blackwell Science Ltd

Erscheinungsjahr

2007

Link zum Volltext

Quelle

Wiley-Blackwell subscription journals

Beschreibungen/Notizen

• We have used the Sydney University Stellar Interferometer to measure the angular diameter of β Hydri. This star is a nearby G2 subgiant the mean density of which was recently measured with high precision using asteroseismology. We determine the radius and effective temperature of the star to be 1.814 ± 0.017 R⊙ (0.9 per cent) and 5872 ± 44 K (0.7 per cent) respectively. By combining the radius with the mean density, as estimated from asteroseismology, we make a direct estimate of the stellar mass. We find a value of 1.07 ± 0.03 M⊙ (2.8 per cent), which agrees with published estimates based on fitting in the Hertzsprung–Russell diagram, but has much higher precision. These results place valuable constraints on theoretical models of β Hyi and its oscillation frequencies.