Quantitative Spectroscopy of Deneb

  title={Quantitative Spectroscopy of Deneb},
  author={Florian Schiller and Norbert Przybilla},
Context. Quantitative spectroscopy of luminous BA-type supergiants offers a high potential for modern astrophysics. Detailed studies allow the evolution of massive stars, galactochemical evolution, and the cosmic distance scale to be constrained observationally. Aims. A detailed and comprehensive understanding of the atmospheres of BA-type supergiants is required in order to use this potential properly. The degree to which we can rely on quantitative studies of this class of stars as a whole… 

Quantitative spectroscopy of Galactic BA-type supergiants I. Atmospheric parameters ,

Context. BA-type supergiants show a high potential as versatile indicators for modern astronomy. This paper constitutes the first in a series that aims at a systematic spectroscopic study of Galactic

CNO Abundances of BA-Type Supergiants

Massive BA-type supergiants are among the visually brightest stars in galaxies with active star formation. As such they are versatile tools for studies of stellar and galactochemical evolution.

The chemical abundance analysis of normal early A- and late B-type stars

Context. Modern spectroscopy of early-type stars often aims at studying complex physical phenomena such as stellar pulsation, the peculiarity of the composition of the photosphere, chemical

High-precision atmospheric parameter and abundance determination of massive stars, and consequences for stellar and Galactic evolution

The derivation of high precision/accuracy parameters and chemical abundances of massive stars is of utmost importance to the fields of stellar evolution and Galactic chemical evolution. We

Dissecting galaxies with quantitative spectroscopy of the brightest stars in the Universe

Measuring distances to galaxies, determining their chemical composition, investigating the nature of their stellar populations and the absorbing properties of their interstellar medium are

Karl Schwarzschild Lecture: Dissecting Galaxies with Quantitative Spectroscopy of the Brightest Stars in the Universe

Measuring distances to galaxies, determining their chemical composition, investigating the nature of their stellar populations and the absorbing properties of their interstellar medium are

Extragalactic stellar astronomy with the brightest stars in the universe

Supergiants are objects in transition from the blue to the red (and vice versa) in the uppermost HRD. They are the intrinsically brightest ‘normal’ stars at visual light with absolute visual

Quantitative Spectroscopy of 24 A Supergiants in the Sculptor Galaxy NGC 300: Flux-weighted Gravity-Luminosity Relationship, Metallicity, and Metallicity Gradient

A quantitative spectral analysis of 24 A supergiants in the Sculptor Group spiral galaxy NGC 300 at a distance of 1.9 Mpc is presented. A new method is introduced to analyze low-resolution (~5 Å)

Mixing of CNO-cycled matter in massive stars

Aims. We test predictions of evolution models on mixing of CNO-cycled products in massive stars from a fundamental perspective. Relative changes within the theoretical C:N:O abundance ratios and the

Distances to galaxies from the brightest stars in the Universe

Blue Supergiants (BSGs) are the brightest stars in the universe at visual light with absolute magnitudes up to MV=−10 mag. They are ideal stellar objects for the determination of extragalactic



Quantitative spectroscopy of ba-type supergiants

Luminous BA-type supergiants have enormous potential for modern astrophysics. They allow topics ranging from non-LTE physics and the evolution of massive stars to the chemical evolution of galaxies

Stellar Spectroscopy Far Beyond the Local Group

Multiobject spectroscopic observations of blue supergiants in NGC 3621, a spiral galaxy at a distance of 6.7 Mpc, carried out with the ESO Very Large Telescope and focal reducer/spectrograph are

On the α-Element Abundance Gradients in the Disk of the Sculptor Spiral Galaxy NGC 300

We have carried out a detailed spectral analysis of six early B-type supergiants in the Sculptor Group spiral galaxy NGC 300. To this end, we used state-of-the-art unified blanketed non-local

Spectroscopy of Blue Supergiants in the Spiral Galaxy NGC 300

We have obtained VLT low-resolution (~5 Å) multiobject spectroscopy in the 4000-5000 Å spectral range of about 70 blue supergiant candidates in the Sculptor Group spiral galaxy NGC 300, selected from

The Spectral Energy Distribution and Mass-Loss Rate of the A-Type Supergiant Deneb

A stellar wind module has been developed for the PHOENIX stellar atmosphere code for the purpose of computing non-LTE, line-blanketed, expanding atmospheric structures and detailed synthetic spectra

C II Abundances in Early-Type Stars: Solution to a Notorious Non-LTE Problem

We address a long-standing discrepancy between non-LTE analyses of the prominent C II 4267 and 6578/82 Å multiplets in early-type stars. A comprehensive non-LTE model atom of C II is constructed

A New Extragalactic Distance Determination Method Using the Flux-weighted Gravity of Late B and Early A Supergiants

Stellar evolution calculations predict the flux-weighted gravity g/T and absolute bolometric magnitude of blue supergiants to be strongly correlated. We use medium-resolution multiobject spectroscopy

Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way.

In this paper the fundamental properties of the brightest known stars in our Galaxy are determined for future comparison with results for the most luminous stars in other galaxies. The H-R diagrams

Non-LTE line formation for Ni/ii: Abundances and stellar parameters - Model atom and first results on BA-type stars

A comprehensive model atom for non-LTE line formation calculations for neutral and singly-ionized nitrogen is presented. Highly accurate radiative and collisional atomic data are incorporated,

A spectroscopic atlas of Deneb (A2 Iae) $\lambda\lambda$3826–5212

We present a spectroscopic atlas of Deneb (A2 Iae) obtained with the long camera of the 1.22-m telescope of the Dominion Astrophysical Observatory using Reticon and CCD detectors. For3826-5212 the