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The Stability of Stellar Atmospheres
Publications of the Astronomical Society of Australia, 1984There have been extensive calculations of model atmospheres of stars over the past few decades. Almost all of these calculations have assumed radiative equilibrium. Except for convection, very little work has been done on the stability of the surface layers of stars at small optical depths.
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2004
In this note, the formalism used to compute a simple stellar atmosphere model is described. The definition of a stellar atmosphere is strongly connected with the radiation field crossing the boundary layers of a star: the atmosphere is composed of those layers where photons interact with matter for the last time before leaving the star.
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In this note, the formalism used to compute a simple stellar atmosphere model is described. The definition of a stellar atmosphere is strongly connected with the radiation field crossing the boundary layers of a star: the atmosphere is composed of those layers where photons interact with matter for the last time before leaving the star.
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Kinematics and Physics of Celestial Bodies, 2010
Helium, which was first discovered on the sun with the help of spectral analysis, plays, together with hydrogen, a principal role in astrophysics. We consider here two fundamental quantities: primordial helium abundance formed during Big Bang nucleosynthesis and the current initial helium abundances in nearby stars. It is shown that stellar atmospheres
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Helium, which was first discovered on the sun with the help of spectral analysis, plays, together with hydrogen, a principal role in astrophysics. We consider here two fundamental quantities: primordial helium abundance formed during Big Bang nucleosynthesis and the current initial helium abundances in nearby stars. It is shown that stellar atmospheres
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Stellar atmospheres as a plasma
Il Nuovo Cimento, 1959Equations of motion and Ohm's law for an ionized gas in a stellar atmosphere are presented. Ambiguities in plasma physics relative to the solar atmosphere, sunspots, the heating mechanism of the chromosphere and the corona, and the state of ionization of the solar corona are discussed, The hydromagnetic ambiguities of interplanetary space are discussed
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1973
This report has been prepared by the President in collaboration with the Secretary of the Commission. It is based on (1) material supplied by those members and associates of the Commission who responded to requests made in our circulars, (2) a bibliographical search intended to supplement the above material, (3) discussions with other interested ...
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This report has been prepared by the President in collaboration with the Secretary of the Commission. It is based on (1) material supplied by those members and associates of the Commission who responded to requests made in our circulars, (2) a bibliographical search intended to supplement the above material, (3) discussions with other interested ...
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1970
Abstract : The research completed under this grant provides an understanding of blue stragglers, partial calibration of the Stromgren uvby and H beta photometric systems, and some initial results concerning the nature of horizontal branch and post-horizontal branch evolution of Population 2 stars.
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Abstract : The research completed under this grant provides an understanding of blue stragglers, partial calibration of the Stromgren uvby and H beta photometric systems, and some initial results concerning the nature of horizontal branch and post-horizontal branch evolution of Population 2 stars.
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1994
Several members of the Organizing Committee as well as Dr. Lee Hartmann have written in their area of expertise for the Report of Commission 36 to the IAU. Their contributions’are assembled here with minimal editing.
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Several members of the Organizing Committee as well as Dr. Lee Hartmann have written in their area of expertise for the Report of Commission 36 to the IAU. Their contributions’are assembled here with minimal editing.
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1988
Commission 36 acted or acts as a sponsor or a cosponsor of the following Symposia and Colloquia.
K. Kodaira +11 more
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Commission 36 acted or acts as a sponsor or a cosponsor of the following Symposia and Colloquia.
K. Kodaira +11 more
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1985
Commission 36 acts as a sponsor or co-sponsor at the following symposia and colloquia: IAU Colloquium No. 90 “Upper Main Sequence Stars with Anomalous Abundances”, Crimea, USSR (May 1985), IAU Colloquium No. 89 “Radiation Hydrodynamics in Stars and Compact Objects”, Copenhagen, Denmark (June 1985), IAU Symposium No.
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Commission 36 acts as a sponsor or co-sponsor at the following symposia and colloquia: IAU Colloquium No. 90 “Upper Main Sequence Stars with Anomalous Abundances”, Crimea, USSR (May 1985), IAU Colloquium No. 89 “Radiation Hydrodynamics in Stars and Compact Objects”, Copenhagen, Denmark (June 1985), IAU Symposium No.
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1992
Schwarzschild’s scientific contributions to the fields of solar physics and of the physics of stellar atmospheres were concentrated in two periods. The first began with his observation of the total solar eclipse of 1905 August 30 in Algeria, and covered the years 1905–1906. After several years break, he again became active in this field in 1913–1914.
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Schwarzschild’s scientific contributions to the fields of solar physics and of the physics of stellar atmospheres were concentrated in two periods. The first began with his observation of the total solar eclipse of 1905 August 30 in Algeria, and covered the years 1905–1906. After several years break, he again became active in this field in 1913–1914.
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