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arXiv · 1011.5123

Uncovering the pulsating photospheres of Mira stars through near-IR interferometry: a case study on R Vir

M. Hillen·T. Verhoelst·B. Acke·P. Degroote
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Abstract

We present the methodology and some preliminary results of our study of the relationship between a Mira's pulsating photosphere and its surrounding molecular layer(s) throughout several pulsation cycles, based on spatially resolved data. Our dataset consists of archival narrow-band observations in the near-infrared H and K bands obtained with the Palomar Testbed Interferometer between 1999 and 2006, extended with a few nights of VLTI AMBER low spectral resolution data and near-infrared SAAO photometry. The fitted model is the geometric star + layer model proposed by Perrin et al. (2004), in which the physical parameters (diameter and temperature of star and layer; wavelength dependent optical depth of the layer) are given a sinusoidal time dependence.

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M. Hillen, T. Verhoelst, B. Acke, P. Degroote. 2010-11-23. Uncovering the pulsating photospheres of Mira stars through near-IR interferometry: a case study on R Vir. https://arxiv.org/abs/1011.5123

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