Results 1 to 10 of about 6,001 (306)
Improving 1D Stellar Models with 3D Atmospheres [PDF]
EPJ Web of Conferences, 2017 Stellar evolution codes play a major role in present-day astrophysics, yet they share common issues. In this work we seek to remedy some of those by the use of results from realistic and highly detailed 3D hydrodynamical simulations of stellar ...
Mosumgaard Jakob Rørsted +4 more
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Astronomy & AstrophysicsContext. M dwarfs are key targets for terrestrial exoplanet studies, with prospects for atmospheric spectroscopy. However, strong stellar magnetic activity and frequent flaring require modelling efforts to assess their impact on planetary atmospheres ...
Mamonova E. +6 more
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LINE FORMATION IN SPECTRA OF X-RAY NOVAE
Odessa Astronomical Publications, 2017 Results of X-ray Novae (XN) optical spectra computation are presented. The continuum and Balmer line are calculated. The model of XN as a self-irradiated accretion disk is used.
V. F. Suleimanov, V. V. Shimansky
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Stark Widths of Ar II Spectral Lines in the Atmospheres of Subdwarf B Stars
Atoms, 2017 Stark broadening parameters are of interest for many problems in astrophysics and laboratory plasmas investigation. Ar II spectral lines are observed in many kinds of stellar atmospheres such as the atmospheres of B-Type stars and subdwarf B stars.
Rafik Hamdi +3 more
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Primordial Lithium from Globular Cluster Turnoff Stars: M13 and M71
The Astrophysical JournalDuring Big Bang nucleosynthesis (BBN) in the first 15 minutes of the Universe, some ^7 Li was created along with isotopes of H and He. The determination of that primordial value of Li can help constrain the conditions at that time.
Ann Merchant Boesgaard +1 more
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Pressure in Stellar Atmospheres [PDF]
Nature, 1911 WITHIN the last fifteen years the spectroscopic equipment applied to the study of both laboratory and celestial investigation has been very materially modified both in dispersive power and design. In the early nineties there were very few of the 21.5-feet Rowland concave grating spectrographs in regular commission for terrestrial research, and it is ...
openaire +1 more source
Characterization of stellar and sub-stellar atmospheres [PDF]
, 2016 In this work I aim characterize a number of (sub)-stellar companions. When studying isolated brown dwarfs, very low-mass stars, and directly imaged exoplanets with insignificant orbital motion, we have to rely on theoretical models to determine basic parameters such as mass, age, and consequently, effective temperature and surface gravity.
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Symmetric Atom–Atom and Ion–Atom Processes in Stellar Atmospheres
Atoms, 2017 We present the results of the influence of two groups of collisional processes (atom–atom and ion–atom) on the optical and kinetic properties of weakly ionized stellar atmospheres layers.
Vladimir A. Srećković +2 more
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Physics of Stellar Atmospheres [PDF]
Nature, 1956 Physik der Sternatmospharen, mit besonderer Berucksichtigung der Sonne Zweite Auflage. Von Prof. A. Unsold. Pp. ix + 866. (Berlin: Springer-Verlag, 1955.) 168 D.M.
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The Astrophysical JournalBlue large-amplitude pulsators (BLAPs) are a recently discovered group of hot pulsating stars whose evolutionary status remains uncertain. Their proposed progenitors are either ≃0.3 M _⊙ shell H-burning stars or ≃1.0 M _⊙ core He-burning stars, both ...
Susmita Das +2 more
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