Observations of Mira stars with the IOTA/FLUOR interferometer and comparison with Mira star models

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 M-type Miras X Oph, R Aql, RU Her, R Ser, and the C-type Mira V CrB we derived the uniform-disk diameters 11.7mas, 10.9mas, 8.4mas, 8.1mas, and 7.9mas (+/- 0.3mas), 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 2970 +/- 110 K. A linear Rosseland radius for R Aql of (250 +100/-60) Rsun was derived from the angular Rosseland radius of 5.5mas +/- 0.2mas and the HIPPARCOS parallax of 4.73mas +/- 1.19mas. The observations were compared with theoretical Mira star models of Bessel et al. (1996) and Hofmann et al. (1998). The effective temperatures of the M-type Miras and the linear radius of R Aql indicate fundamental mode pulsation.

12 pages, 4 postscript figures

Cited by in corpus (9)

• The Mira variable S Ori: Relationships between the photosphere, molecular layer, dust shell, and SiO maser shell at 4 epochs
• The Keck Aperture Masking Experiment: spectro-interferometry of 3 Mira Variables from 1.1 to 3.8 microns
• The Keck Aperture Masking Experiment: Multi-Wavelength Observations of 6 Mira Variables
• Angular Size Measurements Of Mira Variable Stars At 2.2 Microns. II
• The K-band intensity profile of R Leonis probed by VLTI/VINCI
• Diameters of Mira Stars Measured Simultenously in the J,H,K' Near-Infrared Bands
• Joint VLBA/VLTI Observations of the Mira Variable S Orionis
• ATOMIUM: Continuum emission and evidence of dust enhancement from binary motion
• Multi-wavelength interferometry of evolved stars using VLTI and VLBA