121 citations · 806 across the 21 of their papers we have counts for
22 papers
MATISSE unveils a dusty disc in the interior of EP Aquarii. First evidence of a misaligned hierarchical triple system with a central AGB star?
J. Alonso-Hernández, C. Paladini, C. Sánchez Contreras +26
Aims. We have mapped the dust and molecular gas emission distributions in the vicinity (a few stellar radii) of the asymptotic giant branch (AGB) star EP\,Aquarii, with a previousl…
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…
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…
Global 3D radiation-hydrodynamical models of AGB stars with dust-driven winds
Bernd Freytag, Susanne Höfner
Convection and mass loss by stellar winds are two dynamical processes that shape asymptotic giant branch (AGB) stars and their evolution. Observations and earlier 3D models indicat…
Explaining the winds of AGB stars: Recent progress
Susanne Höfner, Bernd Freytag
The winds observed around asymptotic giant branch (AGB) stars are generally attributed to radiation pressure on dust, which is formed in the extended dynamical atmospheres of these…
Global 3D radiation-hydrodynamics models of AGB stars. Effects of convection and radial pulsations on atmospheric structures
Bernd Freytag, Sofie Liljegren, Susanne Höfner
Context: Observations of asymptotic giant branch (AGB) stars with increasing spatial resolution reveal new layers of complexity of atmospheric processes on a variety of scales. Aim…
Aperture synthesis imaging of the carbon AGB star R Sculptoris: Detection of a complex structure and a dominating spot on the stellar disk
M. Wittkowski, K. -H. Hofmann, S. Höfner +16
We present near-infrared interferometry of the carbon-rich asymptotic giant branch (AGB) star R Sculptoris. The visibility data indicate a broadly circular resolved stellar disk wi…
Mass Losing Asymptotic Giant Branch Stars and Supergiants
Patricia A. Whitelock, Martha Boyer, Susanne Höfner +2
This paper presents a summary of four invited and twelve contributed presentations on asymptotic giant branch stars and red supergiants, given over the course of two afternoon spli…
Near-infrared spectro-interferometry of Mira variables and comparisons to 1D dynamic model atmospheres and 3D convection simulations
M. Wittkowski, A. Chiavassa, B. Freytag +4
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 reso…
Exploring wind-driving dust species in cool luminous giants III. Wind models for M-type AGB stars: dynamic and photometric properties
S. Bladh, S. Höfner, B. Aringer +1
Stellar winds observed in asymptotic giant branch (AGB) stars are usually attributed to a combination of stellar pulsations and radiation pressure on dust. Shock waves triggered by…
Abundance analysis for long-period variables II. RGB and AGB stars in the globular cluster 47\,Tuc
Thomas Lebzelter, Walter Nowotny, Kenneth H. Hinkle +2
Asymptotic giant branch (AGB) stars play a key role in the enrichment of galaxies with heavy elements. Due to their large amplitude variability, the measurement of elemental abunda…
Exploring wind-driving dust species in cool luminous giants II. Constraints from photometry of M-type AGB stars
Sara Bladh, Susanne Höfner, Walter Nowotny +1
The heavy mass loss observed in evolved asymptotic giant branch (AGB) stars is usually attributed to a two-stage process: atmospheric levitation by pulsation-induced shock waves, f…
Dust driven mass loss from carbon stars as function of stellar parameters - II. Effects of grain size on wind properties
Lars Mattsson, Susanne Höfner
[Abridged] In this paper we explore grain size effects on wind properties of carbon stars, using a generalized description of radiative cross sections valid for particles of arbitr…
Observing and modeling the dynamic atmosphere of the low mass-loss C-star R Sculptoris at high angular resolution
Stéphane Sacuto, Bernhard Aringer, Josef Hron +4
We study the circumstellar environment of the carbon-rich star R Scl using the near- and mid-infrared high spatial resolution observations from the ESO-VLTI instruments VINCI and M…
Line formation in AGB atmospheres including velocity effects. Molecular line profile variations of long period variables
W. Nowotny, S. Hoefner, B. Aringer
The atmospheres of evolved red giants are considerably influenced by pulsations of the stellar interiors and developing stellar winds. The resulting complex velocity fields severel…
Dust driven mass loss from carbon stars as a function of stellar parameters - I. A grid of Solar-metallicity wind models
Lars Mattsson, Rurik Wahlin, Susanne Hoefner
[Abridged] We have computed a grid of 900 numeric dynamic model atmospheres (DMAs) using a well-tested computer code. This grid of models covers most of the expected combinations o…
Interferometric properties of pulsating C-rich AGB stars I. Intensity profiles and uniform disc diameters of dynamic model atmospheres
C. Paladini, B. Aringer, J. Hron +3
We present the first theoretical study on center-to-limb variation (CLV) properties and relative radius interpretation for narrow and broad-band filters, on the basis of a set of d…
Intense Mass Loss from C-rich AGB Stars at low Metallicity?
L. Mattsson, R. Wahlin, S. Höfner +1
We argue that the energy injection of pulsations may be of greater importance to the mass-loss rate of AGB stars than metallicity, and that the mass-loss trend with metallicity is…
Thresholds for the Dust Driven Mass Loss from C-rich AGB Stars
Lars Mattsson, Rurik Wahlin, Susanne Hoefner
It is well established that mass loss from AGB stars due to dust driven winds cannot be arbitrarily low. We model the mass loss from carbon rich AGB stars using detailed frequency-…
On the Connection between Mass Loss and Evolution of C-rich AGB stars
Lars Mattsson, Susanne Hoefner, Rurik Wahlin +1
The mass loss properties of carbon AGB stars are not very well constrained at present. A variety of empirical or theoretical formulae with different parameterisations are available…
Mass Loss Evolution and the Formation of Detached Shells around TP-AGB Stars
Lars Mattsson, Susanne Hoefner, Falk Herwig
The origin of the so called 'detached shells' around AGB stars is not fully understood, but two common hypotheses state that these shells form either through the interaction of dis…