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The Influence of Chemi-Ionization and Recombination Processes on Spectral Line Shapes in Stellar Atmospheres

open access: yesOpen Astronomy, 2011
The chemi-ionization processes in atom - Rydberg atom collisions, as well as the corresponding chemi-recombination processes, are considered as factors of influence on the atom exited-state populations in weakly ionized layers of stellar atmospheres. The
Mihajlov Anatolij A.   +3 more
doaj   +3 more sources

Radiative transfer in stellar atmospheres [PDF]

open access: yesEAS 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.
Kubat, Jiri
core   +2 more sources

Improving 1D Stellar Models with 3D Atmospheres [PDF]

open access: yesEPJ 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
doaj   +2 more sources

Measuring the magnetic fields in the chromospheres of low-mass stars [PDF]

open access: yesNature Communications
Magnetic fields in the upper atmospheres of solar-like stars are believed to provide an enormous amount of energy to power the hot coronae and drive large-scale eruptions that could impact the habitability of planetary systems around these stars. However,
Tianqi Cang   +13 more
doaj   +3 more sources

Stellar coronal mass ejections [PDF]

open access: yesSerbian Astronomical Journal, 2022
Stellar coronal mass ejections (CMEs) are a growing research field, especially during the past decade. The large number of so far detected exoplanets raises the open question for the CME activity of stars, as CMEs may strongly affect ...
Leitzinger M., Odert P.
doaj   +1 more source

Quantifying the Key Factors Affecting the Escape of Planetary Atmospheres

open access: yesThe Astrophysical Journal, 2023
The habitability of Earth-like planets is an increasingly important subject in astrophysics and in planetary sciences. Atmospheric escape plays a vital role in the evolution of the habitability of Earth-like planets.
J. Luo, H.-Q. He, G.-S. Tong, Jiao Li
doaj   +1 more source

Atmospheric Reconnaissance of TRAPPIST-1 b with JWST/NIRISS: Evidence for Strong Stellar Contamination in the Transmission Spectra

open access: yesThe Astrophysical Journal Letters, 2023
TRAPPIST-1 is a nearby system of seven Earth-sized, temperate, rocky exoplanets transiting a Jupiter-sized M8.5V star, ideally suited for in-depth atmospheric studies.
Olivia Lim   +24 more
doaj   +1 more source

Nonthermal Motions and Atmospheric Heating of Cool Stars

open access: yesThe Astrophysical Journal, 2023
The magnetic processes associated with the nonthermal broadening of optically thin emission lines appear to carry enough energy to heat the corona and accelerate the solar wind.
S. Boro Saikia   +8 more
doaj   +1 more source

Non-Thermal Nitric Oxide Formation in the Earth’s Polar Atmosphere

open access: yesAtmosphere, 2023
Auroral events are the prominent manifestation of solar/stellar forcing on planetary atmospheres because they are closely related to the stellar energy deposition by and evolution of planetary atmospheres.
Valery Shematovich   +2 more
doaj   +1 more source

Investigation of ρ Cas (HR 9045, HD 224014) stellar atmosphere [PDF]

open access: yesSerbian 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.
doaj   +1 more source

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