Title:
Observations of MIRA stars with the IOTA/FLUOR interferometer and comparison with MIRA star models
Authors:
Hofmann, Karl-Heinz; Beckmann, Udo; Bloecker, Thomas; Coude du Foresto, Vincent; Lacasse, Marc G.; Millan-Gabet, Rafael; Morel, Sebastien; Pras, B.; Ruilier, Cyril; Schertl, Dieter; Scholz, Michael; Shenavrin, V.; Traub, Wesley A.; Weigelt, Gerd; Wittkowski, M.; Yudin, B.
Affiliation:
AA(Max-Planck-Institut fuer Radioastronomie) AD(Observatoire de Paris-Meudon) AE(Harvard-Smithsonian Ctr. for Astrophysics) AI(Observatoire de Paris-Meudon) AJ(Max-Planck-Institut fuer Radioastronomie) AK(Univ. Heidelberg) AL(Sternberg Astronomical Institute) AM(Harvard-Smithsonian Ctr. for Astrophysics) AN(Max-Planck-Institut fuer Radioastronomie) AP(Sternberg Astronomical Institute)
Journal:
Proc. SPIE Vol. 4006, p. 688-695, Interferometry in Optical Astronomy, Pierre J. Lena; Andreas Quirrenbach; Eds. (SPIE Homepage)
Publication Date:
07/2000
Origin:
SPIE
Abstract Copyright:
(c) 2000 SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Bibliographic Code:
2000SPIE.4006..688H

Abstract

We present K-band observations of five Mira stars with the IOTA interferometer. The interferograms were obtained with the FLUOR fiber optics beam combiner which provides high- accuracy visibility measurements in spite of time-variable atmospheric conditions. For the Mira stars X Oph, R Aql, RU Her, R Ser, and V CrB we derived the uniform-disk diameters 11.7 mas, 10.9 mas, 8.4 mas, 8.1 mas, and 7.9 mas (+/- 0.3 mas), respectively. Simultaneous photometric observations yielded the bolometric fluxes. The derived angular Rosseland radii and the bolometric fluxes allowed the determination of effective temperatures. For instance, the effective temperature of R Aql was determined to be 3072 K +/- 161 K. A Rosseland radius for R Aql of 250 R. +/- 63 R. was derived from the angular Rosseland radius of 5.5 mas +/- 0.2 mas and the HIPPARCOS parallax of 4.73 mas +/- 1.19 mas. The observations were compared with theoretical Mira star models (D/P model Rosseland radius equals 255 R.; measured R Aql Rosseland radius equals 250 R. +/- 63 R.).