Abstract: | An investigation of the stability of the transfer function of the European Southern Observatory's Very Large Telescope Interferometer has been carried out through observations of Fomalhaut, which was observed over a range in hour angle from 21:50–05:24 on 20 October 2002. No significant variation in the transfer function was found for the zenith angle range 5°–70°. The projected baseline varied between 139.7 m and 49.8 m during the observations and, as an integral part of the determination of the transfer function, a new accurate limb‐darkened angular diameter for Fomalhaut of 2.109 ± 0.013 mas has been established. This has led to improved values for the emergent flux = (3.43 ± 0.10)×108 Wm?2, effective temperature = 8819 ± 67 K and radius = (1.213 ± 0.011)×109 m (R/R⊙ = 1.744 ± 0.016). The luminosity has been found to be (6.34 ± 0.20)×1027 W (L/L⊙ = 16.5 ± 0.5). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |