相关论文: Evolved stars with complex atmospheres - the high …

Long-period variability in luminous red giants has several promising applications, all of which require models able to accurately predict pulsation periods. Linear pulsation models have proven successful in reproducing the observed periods…

We consider some aspects of the evolution of massive stars which can only be elucidated by means of "indirect" observations, i.e. measurements of the effects of massive stars on their environments. We discuss in detail the early evolution…

X-rays and extreme ultraviolet radiation impacting on a gas produce a variety of effects that, depending on the electron content, may provide a significant heating of the illuminated region. In a planetary atmosphere of solar composition,…

Stars play a decisive role in our Universe, from its beginning throughout its complete evolution. For a thorough understanding of their properties, evolution, and physics of their outer envelopes, stellar spectra need to be analyzed by…

Gaseous giants are characterized by their deep atmospheres, which lack clear boundaries with their interiors; therefore, their internal states could directly influence atmospheric dynamics. So far, most modeling studies have considered deep…

We present submillimeter observations of rotational transitions of carbon monoxide from J = 2 -> 1 up to 7 -> 6 for a sample of Asymptotic Giant Branch stars and red supergiants. It is the first time that the high transitions J = 6 -> 5 and…

We continue our numerical analysis of the morphological and energetic influence of massive stars on their ambient interstellar medium for a 35 solar mass star that evolves from the main sequence through red supergiant and Wolf-Rayet phases,…

We study the brightness variations of galactic red supergiant stars using long-term visual light curves collected by the American Association of Variable Star Observers (AAVSO) over the last century. The full sample contains 48 red…

Massive Wolf-Rayet stars are recognized today to be in a very common, but short, evolutionary phase of massive stars. While our understanding of Wolf-Rayet stars has increased dramatically over the past decades, it remains unclear whether…

Observations of the high redshift Universe, interpreted in the context of a new generation of computer simulated model Universes, are providing new insights into the processes by which galaxies and quasars form and evolve, as well as the…

Gas giants are the most readily detectable exoplanets but fundamental questions about their system architectures, formation, migration, and atmospheres have been unanswerable with the current generation of ground- and space-based…

Current observations of the Galactic Center (GC) seem to display a core-like distribution of bright stars from $\sim 5"$ inwards. On the other hand, we observe young, massive stars at the GC, with roughly 20-50\% of them in a disc, mostly…

Most current models of low mass red giant stars do not reproduce the observed position of the red giant branch luminosity bump, a diagnostic of the maximum extent of the convective envelope during the first dredge up. Global asteroseismic…

X-ray emission is ubiquitous among massive stars. In the last decade, X-ray observations revolutionized our perception of stellar winds but opened a Pandora's box of urgent problems. X-rays penetrating stellar winds suffer mainly continuum…

Late type giants (RGB/AGB stars) will be important tracers of the Galactic morphology and evolution in the framework of Gaia, as they are intrinsically bright and thus can probe distant stellar populations or those obscured by interstellar…

The results of a comparative analysis of the elemental abundances in the atmospheres of 14 red giants with high Galactic space velocities are presented. For almost all of the chemical elements considered, the their abundance trends with…

Stellar photometry of nearby irregular galaxies of the Local Group is used to identify and study the young and old stellar populations of these galaxies. An analysis of the spatial distributions of stars of different ages in face-on…

By extending our self-consistent MHD simulations for the solar wind, we study the evolution of stellar winds of solar-type stars from early main sequence stage to red giant phase. Young solar-type stars are active and the mass loss rates…

We present a near-infrared spectro-interferometric observation of the non-Mira-type, semiregular asymptotic giant branch star SW Vir. Our aim is to probe the physical properties of the outer atmosphere with spatially resolved data in…

The Next Generation Very Large Array will have excellent sensitivity for detecting the thermal emission from massive stars and from red giants. This will allow direct imaging of the winds for a large number of hot massive stars. It will…