141 citations · 511 across the 16 of their papers we have counts for
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VLTI-GRAVITY measurements of cool evolved stars: II. Pulsation properties and mass-loss process of the Mira star R Car and the red supergiant VX Sgr
D. Jadlovský, M. Wittkowski, A. Chiavassa +9
The mass-loss process of red supergiant (RSG) and asymptotic giant branch (AGB) stars and its relation to variability are poorly constrained. We study two evolved stars, the Mira-t…
Multi-mode Pulsations in AGB Stars: Insights from 3D RHD CO5BOLD Simulations
Arief Ahmad, Bernd Freytag, Susanne Höfner
Stars on the AGB can exhibit acoustic pulsation modes of different radial orders, along with non-radial modes. These pulsations are essential to the mass-loss process and influence…
Dimming events of evolved stars due to clouds of molecular gas. Scenarios based on 3D radiation-hydrodynamics simulations with CO5BOLD
Bernd Freytag, Susanne Höfner, Bernhard Aringer +1
The dramatic dimming episode of the red supergiant Betelgeuse in 2019/2020, caused by a partial darkening of the stellar disk, has highlighted gaps in the understanding of the evol…
Retrieving stellar parameters and dynamics of AGB stars with Gaia parallax measurements and CO5BOLD RHD simulations
E. Béguin, A. Chiavassa, A. Ahmad +2
Context. The complex dynamics of asymptotic giant branch (AGB) stars and the resulting stellar winds have a significant impact on the measurements of stellar parameters and amplify…
Asymmetries in asymptotic giant branch stars and their winds. I. From 3D RHD models to synthetic observables
Joachim Wiegert, Bernd Freytag, Susanne Höfner
[Abridged] AGB stars are significant contributors to the metal enrichment of the interstellar medium. In this paper, we adapted models from advanced RHD simulations as input for ra…
A new dimension in the variability of AGB stars: convection patterns size changes with pulsation
A. Rosales-Guzmán, J. Sanchez-Bermudez, C. Paladini +16
Stellar convection plays an important role in atmospheric dynamics, wind formation and the mass-loss processes in Asymptotic Giant Branch (AGB) stars. However, a direct characteriz…
Is Betelgeuse Really Rotating? Synthetic ALMA Observations of Large-scale Convection in 3D Simulations of Red Supergiants
Jing-Ze Ma, Andrea Chiavassa, Selma E. de Mink +3
The evolved stages of massive stars are poorly understood, but invaluable constraints can be derived from spatially resolved observations of nearby red supergiants, such as Betelge…
VLTI-PIONIER imaging of the red supergiant V602 Carinae
J. B. Climent, M. Wittkowski, A. Chiavassa +7
Context. Red supergiant stars possess surface features and extended molecular atmospheres. Photospheric convection may be a crucial factor of the levitation of the outer atmospheri…
Tomography of the red supergiant star μ Cep
K. Kravchenko, A. Chiavassa, S. Van Eck +3
A tomographic method, aiming at probing velocity fields at depth in stellar atmospheres, is applied to the red supergiant star μ Cep and to snapshots of 3D radiative-hydrodynamics…
Heading Gaia to measure atmospheric dynamics in AGB stars
A. Chiavassa, B. Freytag, M. Schultheis
Context. Asymptotic Giant Branch stars are characterised by complex stellar surface dynamics that affect the measurements and amplify the uncertainties on stellar parameters. The r…
Pathways for Observing Stellar Surfaces Using 3D Hydrodynamical Simulations of Evolved Stars
A. Chiavassa, B. Freytag
Evolved stars are among the largest and brightest stars and they are ideal targets for the new generation of sensitive, high resolution instrumentation that provides spectrophotome…
3D hydrodynamical simulations of evolved stars and observations of stellar surfaces
A. Chiavassa, B. Freytag
Evolved stars are among the largest and brightest stars and they are ideal targets for the new generation of sensitive, high resolution instrumentation that pro- vides spectrophoto…
Radiative hydrodynamics simulations of red supergiant stars. III. Spectro-photocentric variability, photometric variability, and consequences on Gaia measurements
A. Chiavassa, E. Pasquato, A. Jorissen +8
Context. It has been shown that convection in red supergiant stars gives rise to large granules causing surface inhomogeneities together with shock waves in the photosphere. The re…
Radiative hydrodynamics simulations of red supergiant stars: II. simulations of convection on Betelgeuse match interferometric observations
A. Chiavassa, X. Haubois, J. S. Young +4
Context. The red supergiant (RSG) Betelgeuse is an irregular variable star. Convection may play an important role in understanding this variability. Interferometric observations ca…
Radiative hydrodynamics simulations of red supergiant stars: I. interpretation of interferometric observations
A. Chiavassa, B. Plez, E. Josselin +1
Context. It has been suggested that convection in Red Supergiant (RSG) stars gives rise to large-scale granules causing observable surface inhomogeneities. This convection is also…