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On the Radiative Equilibrium of a Stellar Atmosphere. VIII.

open access: bronzeThe Astrophysical Journal, 1945
In this paper the methods developed in earlier papers are extended to solving the problem of radiative transfer in curved atmospheres, i.e., to solving the equation of transfer μ∂l/∂r+(1-μ 2 )/r 2 ∂l/∂μ=-κρI+½κρ∫ +1 -1 Idμ, where κρ is a function only of r.
S. Chandrasekhar
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Pressure in Stellar Atmospheres [PDF]

open access: bronzeNature, 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 ...
C. P. Butler
openalex   +4 more sources

On the Radiative Equilibrium of a Stellar Atmosphere. XIX.

open access: bronzeThe Astrophysical Journal, 1947
In this paper we tabulate the various H-functions which occur in the solutions of transfer problems involving Rayleigh's phase function and Rayleigh scattering (including the state of polarization of the scattered radiation). The H-functions have been determined numerically as the solutions of the exact functional equations which they satisfy.
S. Chandrasekhar, Frances H. Breen
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Abundance of Helium in Stellar Atmospheres [PDF]

open access: bronzeHighlights of Astronomy, 1971
Helium abundance in stellar atmospheres has been the subject of several recent investigations, essentially induced by progresses in the computation of non-grey model atmospheres (including line blanketing in the far U.V.), by considerable advances in the theory of Stark broadening of helium lines, by non local thermodynamic equilibrium (LTE) work for ...
R. Cayrel
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Microlensing and the Physics of Stellar Atmospheres

open access: green, 2000
8 pages including 6 figures. To appear in ``Microlensing 2000: A New Era of Microlensing Astrophysics,'' an ASP conference proceedings, eds. J.W.
Penny D. Sackett
openalex   +5 more sources

Feasibility Analysis of Stellar Refraction Indirect Horizon Sensing Positioning on the Carrier inside the Atmosphere [PDF]

open access: yesHangkong bingqi, 2022
The stellar refraction indirect horizon sensing positioning method has the characteristics of strong auto-nomy, high accuracy and low cost, which is a new celestial navigation method with great application prospect.
Zhan Xianjun, Wang Xinlong, Hu Xiaodong, Ding Xiaokun
doaj   +1 more source

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

open access: yesSerbian 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
doaj   +1 more source

Research on Stellar Occultation Detection with Bandpass Filtering for Oxygen Density Retrieval

open access: yesRemote Sensing, 2023
Stellar occultation instruments detect the transmission of stellar spectra through the planetary atmosphere to retrieve densities of various atmospheric components.
Zheng Li   +6 more
doaj   +1 more source

The stellar atmosphere physical system II. An operative sequential algorithm to solve the stellar atmosphere problem [PDF]

open access: yesSerbian Astronomical Journal, 2019
In this paper, the second and the last of the series, we present a sequential algorithm to solve the stellar atmosphere problem that may serve as a paradigm for the solution of more general non-linear and non-local problems.
Crivellari Lucio
doaj   +1 more source

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