Tomography of cool giant and supergiant star atmospheres

@article{Kravchenko2019TomographyOC,
  title={Tomography of cool giant and supergiant star atmospheres},
  author={Kateryna Kravchenko and Andrea Chiavassa and Sophie Van Eck and Alain Jorissen and Thibault Merle and Bernd Freytag and Bertrand Plez},
  journal={Astronomy \& Astrophysics},
  year={2019}
}
Context. Red supergiants are cool massive stars and are the largest and the most luminous stars in the Universe. They are characterized by irregular or semi-regular photometric variations, the physics of which is not clearly understood. Aims. The paper aims to derive the velocity field in the red supergiant star μ Cep and to relate it to the photometric variability with the help of the tomographic method. Methods. The tomographic method allows one to recover the line-of-sight velocity… 
Tomography of cool giant and supergiant star atmospheres. I. Validation of the method
Cool giant and supergiant star atmospheres are characterized by complex velocity fields originating from convection and pulsation processes which are not fully understood yet. The velocity fields
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We explore the three-dimensional properties of convective, luminous (L ≈ 104.5–105 L ⊙), hydrogen-rich envelopes of red supergiants (RSGs) based on radiation hydrodynamic simulations in spherical
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Aims. We present a spectroscopic analysis of the extremely luminous red star VX Sgr based on high-resolution observations combined with AAVSO light curve data. Given the puzzling characteristics of
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The processes that shape the extended atmospheres of red supergiants (RSGs), heat their chromospheres, create molecular reservoirs, drive mass loss, and create dust remain poorly understood.
Effective temperatures of red supergiants estimated from line-depth ratios of iron lines in the YJ bands, 0.97-1.32μm
Determining the effective temperatures (Teff) of red supergiants (RSGs) observationally is important in many fields of stellar physics and galactic astronomy, yet some significant difficulties
A Massive Star’s Dying Breaths: Pulsating Red Supergiants and Their Resulting Type IIP Supernovae
Massive stars undergo fundamental-mode and first-overtone radial pulsations with periods of 100-1000 days as Red Supergiants (RSGs). At large amplitudes, these pulsations substantially modify the
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References

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Tomography of cool giant and supergiant star atmospheres. I. Validation of the method
Cool giant and supergiant star atmospheres are characterized by complex velocity fields originating from convection and pulsation processes which are not fully understood yet. The velocity fields
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TLDR
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Context. It has been proposed that convection in red supergiant (RSG) stars produces large-scale granules causing observable surface inhomogeneities. This convection is also extremely vigorous and is
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We use moderate-resolution optical spectrophotometry and the new MARCS stellar atmosphere models to determine the effective temperatures of 74 Galactic red supergiants (RSGs). The stars are mostly
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A tomographic method is described that makes it possible to follow the propagation of shock waves across the photosphere of long-period variable stars. The method relies on the correlation of the
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