ar X iv : a st ro - p h / 02 06 40 6 v 1 2 4 Ju n 20 02 Observations of Mira stars with the IOTA / FLUOR interferometer and comparison with Mira star models ⋆

نویسندگان

  • K. - H. Hofmann
  • V. Coudé du Foresto
  • B. Mennesson
  • R. Millan - Gabet
  • C. Ruilier
  • D. Schertl
  • W. Traub
  • M. Wittkowski
  • B. Yudin
چکیده

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 11.7 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 2970 ±110 K.

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

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.

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تاریخ انتشار 2002