Results 21 to 30 of about 4,175 (313)
Stellar fluxes as probes of convection in stellar atmospheres [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractConvection and turbulence in stellar atmospheres have a significant effect on the emergent flux from late-type stars. The theoretical advancements in convection modelling over recent years have proved challenging for the observers to obtain measurements with sufficient precision and accuracy to allow discrimination between the various ...
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The spectroscopic study of M8.5-M9.5 stars and brown dwarfs
EPJ Web of Conferences, 2013 We present high-resolution spectra analysis of the three late-M dwarfs LP944-20, SIPS J2045-6332 and DENIS-P J0021.0-4244. The stellar spectra were observed with Very Large Telescope/Ultraviolet–Visual Echelle Spectrograph (VLT/UVES) in optical and near ...
Pavlenko Y.V. +2 more
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Technetium in Stellar Atmospheres [PDF]
Symposium - International Astronomical Union, 1991 The quantitative determinations of technetium abundances are discussed. Up to now Tc abundances were found for nearly 30 stars which all are thermally pulsing AGB stars. The technetium abundance values for these AGB stars atmospheres, where it was found to be present, cluster around −1.0 ÷ 1.7.
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Radiative Transfer in Stellar Atmospheres [PDF]
EAS Publications Series, 2010 This review presents basic equations for the solution of the NLTE radiative transfer problem for trace elements and methods for its solution are summarized. The importance of frequency coupling in radiative transfer in stellar atmospheres is emphasized.
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New Methods in Modeling of Hot Stellar Atmospheres
Open Astronomy, 2013 In the present study we had three main aims. First to study the possibility of reducing the initial model atmosphere data to short analytical polynomials.
Sapar A., Poolamäe R., Sapar L.
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Influence of stellar variability on the determination of the radius during a transit of an exoplanet
EPJ Web of Conferences, 2011 Stellar variability can affect the estimate of an exoplanet radius measured during a transit. We developed a transit light curve model which includes stellar spots.
Désert J.-M. +3 more
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The Inhomogeneity Effect. I. Inhomogeneous Surface and Atmosphere Accelerate Planetary Cooling
The Astrophysical Journal, 2023 We propose a general principle that under radiative-convective equilibrium, the spatial and temporal variations in a planet’s surface and atmosphere tend to increase its cooling.
Xi Zhang
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Improving 1D Stellar Models with 3D Atmospheres
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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Double Trouble: Two Transits of the Super-Earth GJ 1132 b Observed with JWST NIRSpec G395H
The Astrophysical Journal Letters, 2023 The search for rocky planet atmospheres with JWST has focused on planets transiting M dwarfs. Such planets have favorable planet-to-star size ratios, enhancing the amplitude of atmospheric features.
E. M. May +21 more
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Atoms, 2023 Stellar atmospheres separate the hot and dense stellar interiors from the emptiness of space. Radiation escapes from the outermost layers of a star, carrying direct physical information.
Carlos Allende Prieto
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