Title:
Interferometric observations of evolved stars in the L'band
Authors:
Chagnon, Gilles; Mennesson, Bertrand P.; Perrin, Guy S.; Coude du Foresto, Vincent; Lacasse, Marc G.
Affiliation:
AA(Observatoire de Paris-Meudon (France)), AB(Jet Propulsion Lab. (USA)), AC(Observatoire de Paris-Meudon (France)), AD(Observatoire de Paris-Meudon (France)), AE(Harvard-Smithsonian Ctr. for Astrophysics (USA))
Journal:
Interferometry for Optical Astronomy II. Edited by Wesley A. Traub. Proceedings of the SPIE, Volume 4838, pp. 185-192 (2003). (SPIE Homepage)
Publication Date:
02/2003
Origin:
SPIE
Abstract Copyright:
(c) 2003: SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Bibliographic Code:
2003SPIE.4838..185C

Abstract

Ten bright Miras and eight semi-regular variable giants and supergiants have been observed with the IOTA (Infrared and Optical Telescope Array) interferometer in the L' band (from 3.4 to 4.1 microns). Observations were carried out in March and November 2000 with the FLUOR/TISIS instrument. Variations in the diameter of R Leo are for the first time observed in the L' band, and our data show that the diameter of α Ori is remarkably stable. Important deviations from a uniform disk model are demonstrated for most of the Mira stars of our sample, and are particularly obvious for χ Cyg, R Cas and ο Cet. Observations of α Her carried out in March are consistent with previous estimates of its diameter published with the very first data of TISIS. The instrument has shown its reliability and the good quality of its data. The present results emphasize the importance of such data for a better comprehension of the circumstellar environment of evolved stars.