Stellar Angular Diameters and Linear Radii from Optical Interferometry

Session 67 - Stars: Evolution, Atmospheres, Intrinsic.
Display session, Thursday, June 11
Atlas Ballroom,

[67.04] Stellar Angular Diameters and Linear Radii from Optical Interferometry

T. E. Nordgren, M. Dyck (USNO Astrometry Dept.), J. Sudol (Univ. of Wyoming), M. Germain, C. A. Hummel, J. A. Benson (USNO Astrometry Dept.)

As part of a stellar effective temperature study we present angular diameters and radii for a sample of evolved stars measured with the Navy Prototype Optical Interferometer (NPOI). We have calculated limb darkened diameters from the observed uniform disks using standard conversion factors. Diameters are consistently measured for stars as small as 2.0 mas with a one sigma error of 0.2 mas. For stars which have been observed over many nights the derived diameters for each night are consistent with one another to a precision of 15 percent. In conjunction with stellar angular diameters derived using the Infrared Optical Telescope Array (IOTA) and lunar occulations we calculate true stellar radii using recent Hipparcos parallaxes.

Program listing for Thursday