Structure of the outer layers of cool standard stars

  title={Structure of the outer layers of cool standard stars},
  author={S. Dehaes and Eva Bauwens and Leen Decin and Kjell Eriksson and Gert Raskin and Bryan J. Butler and Charles Darren Dowell and Babar Ali and Joris Blommaert},
  journal={Astronomy and Astrophysics},
Context. Among late-type red giants, an interesting change occurs in the structure of the outer atmospheric layers as one moves to later spectral types in the Hertzsprung-Russell diagram: a chromosphere is always present, but the coronal emission diminishes and a cool massive wind steps in. Aims. Where most studies have focussed on short-wavelength observations, this article explores the influence of the chromosphere and the wind on long-wavelength photometric measurements. The goal of this… 

Systematic trend of water vapour absorption in red giant atmospheres revealed by high resolution TEXES 12 mu m spectra

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Although observational data unequivocally point out to the presence of chromospheres in red giant stars, no attempts have been made so far to model them using 3D hydrodynamical model atmospheres. We

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We present all Herschel PACS photometer observations of Mars, Saturn, Uranus, Neptune, Callisto, Ganymede, and Titan. All measurements were carefully inspected for quality problems, were reduced in a

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Context. The mass-loss mechanism in red giants and red supergiants is not yet understood well. The SiO fundamental lines near 8 μm are potentially useful for probing the outer atmosphere, which is

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Aims. We present a high-spatial and high-spectral resolution observation of the well-studied K giant Aldebaran with AMBER at the Very Large Telescope Interferometer (VLTI). Our aim is to spatially

Herschel-PACS photometry of faint stars

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In this thesis, I present BLAST observations of the Carina Nebula and Herschel observations of NGC7538. I use the source extracting routine CSAR to identify 172 source in Carina and 94 sources in

Herschel celestial calibration sources

Celestial standards play a major role in observational astrophysics. They are needed to characterise the performance of instruments and are paramount for photometric calibration. During the Herschel

Herschel celestial calibration sources Four large main-belt asteroids as prime flux calibrators for the far-IR/sub-mm range

Celestial standards play a major role in observational astrophysics. They are needed to characterise the performance of instruments and are paramount for photometric calibration. During the Herschel



Continuum emission around AGB stars at 1.2 mm

It is generally acknowledged that the mass-loss of asymptotic giant branch (AGB) stars undergoes variations on different time-scales. We constructed models for the dust envelopes for a sample of AGB

ISO-SWS calibration and the accurate modelling of cool-star atmospheres ? IV. G9 to M2 stars ??

A detailed spectroscopic study of 11 giants with spectral type from G9 to M2 is presented. The 2.38-4.08 m wavelength-range of band 1 of ISO-SWS (Short-Wavelength Spectrometers on board of the

A radio-continuum survey of the coolest M and C giants

A VLA continuum survey of 22 cool M and C type giants and supergiants has been conducted in order to investigate the physical properties of the partially ionized, expanding chromospheres of the

Circumstellar material in the Vega inner system revealed by CHARA/FLUOR

Context. Only a handful of debris disks have been imaged up to now. Due to the need for high dynamic range and high angular resolution, very little is known about the inner planetary region, where

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We describe state-of-the-art MARCS-code model atmospheres generated for a group of A dwarf, G dwarf, and late-G to mid-K giant standard stars, selected to photometrically calibrate the Spitzer Space

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We report results of an Einstein Guest Observing program to map the occurrence of soft x-ray emission, which is a signature of hot stellar coronae (T>10/sup 6/ K), in the cool half of the Hertzsprung

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Soft X-ray detections of stellar coronae (T ~ 106 K) are rare in the giant branch redward of ~K1 III. We have conducted a less direct—but more sensitive—search using the Hubble Space Telescope

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We have imaged two normal, noncoronal, infrared-bright K giants, α Tau and α Boo, in the 1.4 and 2.8 mm continua using BIMA. These stars have been used as important absolute calibrators for several

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