Related papers: Dynamical Opacity-Sampling Models of Mira Variable…
We present 4 model series of the CODEX dynamical opacity-sampling models of Mira variables with solar abundances, designed to have parameters similar to $o$ Cet, R Leo and R Cas. We demonstrate that the CODEX models provide a clear physical…
Our comprehension of stellar evolution on the AGB still faces many difficulties. To improve on this, a quantified understanding of large-amplitude pulsator atmospheres and interpretation in terms of their fundamental stellar parameters are…
Atmospheres of evolved AGB stars are heavily affected by pulsation, dust formation and mass loss, and they can become very extended. Time series of observed high-resolution spectra proved to be a useful tool to study atmospheric dynamics…
We obtained a total of 20 near-infrared K-band spectro-interferometric snapshot observations of the Mira variables o Cet, R Leo, R Aqr, X Hya, W Vel, and R Cnc with a spectral resolution of about 1500. We compared observed flux and…
Diffuse envelopes around Mira variables are among the most important sources influencing the chemical evolution of galaxies. However they represent an observational challenge because of their complex spectral features and their rapid…
The prototypical Mira variable, $o$ Cet (Mira), has been observed as a Science Verification target in the 2014 ALMA Long Baseline Campaign with a longest baseline of 15 km. ALMA clearly resolves the images of the continuum and molecular…
Originating in different depths of the very extended atmospheres of AGB stars, various molecular spectral lines observable in the near-infrared show diverse behaviours and can be used to probe atmospheric dynamics throughout the outer…
We have modelled the circumstellar envelope of {\it o} Ceti (Mira) using new observational constraints. These are obtained from photospheric light scattered in near-IR vibrational-rotational lines of circumstellar CO molecules at 4.6…
The formation of dust with temperature-dependent non-grey opacity is considered in a series of self-consistent model atmospheres at different phases of an O-rich Mira variable of mass 1.2 $M_\odot$. Photometric and interferometric…
Based on an extensive spectral study of a photometrically confirmed sample of Mira variables, we find a relationship between relative Balmer emission-line strength and spectral temperature of O-rich Mira stars. The $F_{\rm H\delta}/F_{\rm…
We test our knowledge of the atomic opacity in the solar UV spectrum. Using the atomic data compiled in Paper I from modern, publicly available, databases, we perform calculations that are confronted with space-based observations of the…
We present a possible interpretation for the increase of the angular diameter of the Mira variables o Cet, R Leo, and chi Cyg from the K band to the 11 micron region revealed by the recent interferometric observations using narrow…
The atmospheric structure of Mira variables is considerably influenced by pulsation. Molecular absorption lines in the near-infrared (NIR), especially second overtone CO lines, show therefore a characteristic behaviour in time-series of…
Multi-dimensional unified model atmospheres with winds of massive stars have so far been studied under the assumption of equal flux, Planck, and energy weighted mean opacities, which effectively means these models have been in local…
A survey of CO(3-2) emission from optically visible oxygen-rich Mira variable stars within 500 pc of the sun was conducted. A molecular envelope was detected surrounding 36 of the 66 stars examined. Some of these stars have lower outflow…
The time variation in the water-vapour bands in oxygen-rich Mira variables has been investigated using multi-epoch ISO/SWS spectra of four Mira variables in the 2.5-4.0 micron region. All four stars show H2O bands in absorption around…
We study the near-infrared properties of 690 Mira candidates in the central region of the Large Magellanic Cloud, based on time-series observations at JHKs. We use densely-sampled I-band observations from the OGLE project to generate…
Dynamic model atmospheres of Mira stars predict variabilities in the photospheric radius and in atmospheric molecular layers which are not yet strongly constrained by observations. Here we measure the variability of the oxygen-rich Mira…
Context. We study the atmosphere of the carbon-rich Mira RU Vir using the mid-infrared high spatial resolution interferometric observations from VLTI/MIDI. Aims. The aim of this work is to analyse the atmosphere of the carbon-rich Mira RU…
Aims. We study the effects of moderate deviations from solar abundances upon the atmospheric structure and colours of typical Mira variables. Methods. We present two model series of dynamical opacity-sampling models of Mira variables which…