Interferometric Constraints on Balmer-Line Limb Darkening in A-type Supergiant Stars
Benjamin Katz
Only one A-type supergiant, Deneb, has a measured angular diameter from long-baseline interferometric measurements. The next two brightest A-type supergiants, η Leo and ν Cep, are expected to have angular diameters below 1 milliarcsecond, well matched for the angular resolution of intensity interferometry with Imaging Air Cherenkov Telescope (IACT) arrays, such as VERITAS. While VERITAS has measured stars in a wide (20 nm) band, measurements in a very narrow band containing only the Hδ line have