Results 11 to 20 of about 197,159 (337)

The stellar atmosphere physical system I. Phenomenological definition and representation of a stellar atmosphere [PDF]

Serbian Astronomical Journal, 2018
This paper is the first in a series of two that deals with the physical and numerical grounds of stellar atmosphere modelling. After a phenomenological definition of a star and stellar atmosphere, the physics that shapes the stellar atmosphere ...
Crivellari Lucio
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Spectroscopic Follow-up of Gaia Exoplanet Candidates: Impostor Binary Stars Invade the Gaia DR3 Astrometric Exoplanet Candidates

The Astronomical Journal, 2023
In this paper, we report on the follow-up of six potential exoplanets detected with Gaia astrometry and provide an overview of what is currently known about the nature of the entire Gaia astrometric exoplanet candidate sample, 72 systems in total.
Marcus L. Marcussen, Simon H. Albrecht
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Theoretical Predictions of Surface Light Element Abundances in Protostellar and Pre-Main Sequence Phase

Frontiers in Astronomy and Space Sciences, 2021
Theoretical prediction of surface stellar abundances of light elements–lithium, beryllium, and boron–represents one of the most interesting open problems in astrophysics.
E. Tognelli, E. Tognelli, S. Degl’Innocenti, S. Degl’Innocenti, P. G. Prada Moroni, P. G. Prada Moroni, L. Lamia, L. Lamia, L. Lamia, R. G. Pizzone, A. Tumino, A. Tumino, C. Spitaleri, C. Spitaleri, A. Chiavassa   +14 more
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Observational Tests and Predictive Stellar Evolution II: Non-standard Models [PDF]

, 2004
We examine contributions of second order physical processes to results of stellar evolution calculations amenable to direct observational testing. In the first paper in the series (Young et al.
Andersen J., Blocker T., Charbonnel C., David Arnett, Grevesse N., Kudritzki R. P., Lastennet E., Latham D. W., Patrick A. Young, Pols O. R., Stickland D. J., Stickland D. J.   +11 more
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Turbulence-supported Massive Star Envelopes

The Astrophysical Journal Letters, 2023
The outer envelopes of massive ( M ≳ 10 M _⊙ ) stars exhibit large increases in opacities from forests of lines and ionization transitions (particularly from iron and helium) that trigger near-surface convection zones. One-dimensional (1D) models predict
William C. Schultz, Lars Bildsten, Yan-Fei Jiang   +2 more
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Hot super-Earths stripped by their host stars

Nature Communications, 2016
Theory predicts a deficit of super-Earth sized planets, which orbit close to their host star. Here, Lundkvist et al. use data from the NASA Kepler mission to show that this deficit is also seen in observations, thereby providing new insight into ...
M. S. Lundkvist, H. Kjeldsen, S. Albrecht, G. R. Davies, S. Basu, D. Huber, A. B. Justesen, C. Karoff, V. Silva Aguirre, V. Van Eylen, C. Vang, T. Arentoft, T. Barclay, T. R. Bedding, T. L. Campante, W. J. Chaplin, J. Christensen-Dalsgaard, Y. P. Elsworth, R. L. Gilliland, R. Handberg, S. Hekker, S. D. Kawaler, M. N. Lund, T. S. Metcalfe, A. Miglio, J. F. Rowe, D. Stello, B. Tingley, T. R. White   +28 more
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Databases of Publications and Observations as a Part of the Crimean Astronomical Virtual Observatory

Open Astronomy, 2015
We describe the main principles of formation of databases (DBs) with information about astronomical objects and their physical characteristics derived from observations obtained at the Crimean Astrophysical Observatory (CrAO) and published in the ...
Shlyapnikov A., Bondar’ N., Gorbunov M.   +2 more
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Investigation of ρ Cas (HR 9045, HD 224014) stellar atmosphere [PDF]

Serbian Astronomical Journal
The atmosphere of hypergiant ρ Cas is investigated by the method of atmospheric model. Effective temperature and the surface of gravity are determined by comparing the observed and theoretical values of photometrical indices [c1];Q, and ...
Samedov Z.A., Hajieva G.M.
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Stellar Flare Statistics - Physical Consequences [PDF]

International Astronomical Union Colloquium, 1989
AbstractThe observational data permit us to establish clear statistical correlations between different parameters of stellar flare activity and the characteristics of quiet stars. These relations are: (i)between energies and frequencies of flares on stars of different luminosities;(ii)between total radiation energies of flares and quiet stars both in X-
openaire   +1 more source

What asteroseismology can do for exoplanets

EPJ Web of Conferences, 2015
We describe three useful applications of asteroseismology in the context of exoplanet science: (1) the detailed characterisation of exoplanet host stars; (2) the measurement of stellar inclinations; and (3) the determination of orbital eccentricity from ...
Van Eylen Vincent, Lund Mikkel N., Silva Aguirre Victor, Arentoft Torben, Kjeldsen Hans, Albrecht Simon, Chaplin William J., Isaacson Howard, Pedersen May G., Jessen-Hansen Jens, Tingley Brandon, Christensen-Dalsgaard Jørgen, Aerts Conny, Campante Tiago L., Bryson Steve T.   +14 more
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