Results 1 to 10 of about 3,144 (170)

A Census of B[e] Supergiants

Galaxies, 2019
Stellar evolution theory is most uncertain for massive stars. For reliable predictions of the evolution of massive stars and their final fate, solid constraints on the physical parameters, and their changes along the evolution and in different ...
Michaela Kraus
doaj   +3 more sources

THE ABUNDANCES OF HEAVY ELEMENTS IN RED SUPERGIANTS OF MAGELLANIC CLOUDS

Odessa Astronomical Publications, 2013
The spectra of Magellanic Clouds (MC) supergiants PMMR23, PMMR144 and RM 1-667 with resolving power R=30,000 and signal to noise ratio near 100 obtained at3.6 metertelescope in Chile were analysed. We present are port on the  detailed investigation of MC
V. Gopka, A Yushchenko, V. Kovtyukh, A. Shavrina, V. Yushchenko, S. Vasilyeva, Y. Pavlenko, S. Andrievsky   +7 more
doaj   +3 more sources

Infrared Model Spectra for Evolving Red Supergiants [PDF]

Journal of Astronomy and Space Sciences, 1993
The space and ground based infrared spectra of red supergiants are modeled and arranged in order of their evolutionary status with their theoretical model parameters. The chemical compositions of the dust shells around red supergiants are affected by the
Kyung-Won Suh
doaj   +1 more source

Physical Properties of 5000 Cool Large Magellanic Cloud Supergiants with Gaia XP Spectra: A Detailed Portrait of the Upper H-R Diagram Hints at Missing Supernova Progenitors

The Astrophysical Journal, 2023
Characterizing the physical properties of cool supergiants allows us to probe the final stages of a massive star’s evolution before it undergoes core collapse. Despite their importance, the fundamental properties of these stars— $\mathrm{log}{T}_{\mathrm{
Trevor Z. Dorn-Wallenstein, Kathryn F. Neugent, Emily M. Levesque   +2 more
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The Complex Upper HR Diagram

Galaxies, 2019
Several decades of observations of the most massive and most luminous stars have revealed a complex upper HR Diagram, shaped by mass loss, and inhabited by a variety of evolved stars exhibiting the consequences of their mass loss histories.
Roberta M. Humphreys
doaj   +1 more source

Variability Survey of Massive Stars in OB-Associations: Preliminary Results on the Cygnus Region

Open Astronomy, 2012
We present V - and I-passband photometry of massive stars in the Cyg OB1 and Cyg OB2 associations, based on about 80 observing nights spanning 300 days in the 2011 season. The variability of 22 supergiants and 48 OB-stars with luminosity classes III-V is
Laur J., Tuvikene T., Eenmäe T., Kolka I., Leedjärv L.   +4 more
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A constant upper luminosity limit of cool supergiant stars down to the extremely low metallicity of I Zw 18

Astronomy & Astrophysics
Stellar wind mass loss of massive stars is often assumed to depend on their metallicity Z. Therefore, evolutionary models predict that massive stars in lower-Z environments are able to retain more of their hydrogen-rich layers and evolve into brighter ...
Schootemeijer Abel, Götberg Ylva, Langer Norbert, Bortolini Giacomo, Hirschauer Alec S., Patrick Lee   +5 more
doaj   +1 more source

X-Shooting ULLYSES: Massive stars at low metallicity

Astronomy & Astrophysics
Context. Hot massive stars lose mass through radiation-driven winds, producing significant chemical, radiative, and mechanical feedback in the surrounding environment.
Alkousa T., Crowther P. A., Bestenlehner J. M., Sana H., Tramper F., Vink J. S., Najarro F., Sander A. A. C., Bernini-Peron M., Oskinova L., van Loon J. Th., Kuiper R.   +11 more
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Painting a family portrait of the yellow super- and hypergiants in the Milky Way

Astronomy & Astrophysics
Context. The distances to evolved massive stars in the Milky Way are poorly constrained by Gaia parallaxes because these stars are bright and variable.
Kasikov A., Mehner A., Kolka I., Aret A.
doaj   +1 more source

WISE J005128.08+645651.7: An enigmatic R Coronae Borealis star

Astronomy & Astrophysics
Context. R Coronae Borealis (RCB) stars are hydrogen-deficient and carbon-rich (HdC) supergiants that likely originate from a merger of two white dwarfs.
Budaj J., Bernhard K., Hubeny I.
doaj   +1 more source