Results 31 to 40 of about 26,787 (255)
CHEMICAL COMPOSITION OF ATMOSPHERES OF COOL GIANT STARS
Odessa Astronomical Publications, 2017 Results of determination of abundances of chemical elements in the atmospheres of 57 giant stars of the oxygen sequence of the Galactic disk axe given.
N. S. Komarov
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An empirical mass-loss law for Population II giants from the Spitzer-IRAC survey of Galactic globular clusters [PDF]
, 2014 The main aim of the present work is to derive an empirical mass-loss (ML) law for Population II stars in first and second ascent red giant branches.
Dalessandro, E. +6 more
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A Distance Measurement to M33 Using Optical Photometry of Mira Variables
The Astronomical Journal, 2023 We present a systematic analysis to determine and improve the pulsation periods of 1637 known long-period Mira variables in M33 using gri -band light curves spanning ∼18 yr from several surveys, including the M33 variability survey, Panoramic Survey ...
Jia-Yu Ou +6 more
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Optical Spectropolarimetry of Asymptotic Giant Branch and Post–Asymptotic Giant Branch Stars
The Astrophysical Journal, 2006 Spectropolarimetric observations are presented for 21 AGB stars, 13 proto-planetary nebulae (PPNs), and two R CrB-type stars. The spectra cover the wavelength range from ~4200 to 8400 A with 16 A resolution. Among the AGB stars, 8 of 14 M giants, five of six carbon stars, and zero of one S star showed intrinsic polarization.
John H. Bieging +3 more
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Planetary Engulfment Prognosis within the ρ CrB System
The Astrophysical Journal, 2023 Exoplanets have been detected around stars at various stages of their lives, ranging from young stars emerging from formation to the latter stages of evolution, including white dwarfs and neutron stars.
Stephen R. Kane
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Pulsations powered by hydrogen shell burning in white dwarfs [PDF]
, 2016 In the absence of a third dredge-up episode during the asymptotic giant branch phase, white dwarf models evolved from low-metallicity progenitors have a thick hydrogen envelope, which makes hydrogen shell burning be the most important energy source.
Althaus, Leandro G. +3 more
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Asymptotic-Giant-Branch Models at Very Low Metallicity [PDF]
Publications of the Astronomical Society of Australia, 2009 AbstractIn this paper we present the evolution of a low-mass model (initial mass M = 1.5 M⊙) with a very low metal content (Z = 5 × 10−5, equivalent to [Fe/H] = –2.44). We find that, at the beginning of the Asymptotic Giant Branch (AGB) phase, protons are ingested from the envelope in the underlying convective shell generated by the first fully ...
Cristallo, S. +5 more
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Mass loss on the Asymptotic Giant Branch [PDF]
Proceedings of the International Astronomical Union, 2006 Mass loss on the Asymptotic Giant Branch provides the origin of planetary nebulae. This paper reviews several relevant aspects of AGB evolution: pulsation properties, mass loss formalisms and time variable mass loss, evidence for asymmetries on the AGB, binarity, ISM interaction, and mass loss at low metallicity.
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CO observations of candidates for carbon-rich asymptotic giant branch and post-asymptotic giant branch stars [PDF]
The Astrophysical Journal, 1993 Circumstellar CO emission has been detected in a number of featureless or weak SiC emission, low color temperature IRAS sources. The CO detections confirm the suggestion that these are either extreme carbon stars, carbon-rich proto-planetary nebulae (PPNs), or carbon-rich planetary nebulae (PNs).
Volk, K, Kwok, S, Woodsworth, AW
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Frontiers in Astronomy and Space Sciences, 2021 Among presolar grains, oxide ones are made of oxygen, aluminum, and a small fraction of magnesium, produced by the 26Al decay. The largest part of presolar oxide grains belong to the so-called group 1 and 2, which have been suggested to form in Red Giant
S. Palmerini +11 more
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