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2012
Numerical solutions to the equations of stellar structure can provide detailed description of the interiors of stars. Some general features of stellar structure can be discovered through these solutions. The mass distribution indicates that for high-mass stars with M ≥ 1. 2 M⊙ over 95 % of the mass is contained within ∼ 60 % of the radius.
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Numerical solutions to the equations of stellar structure can provide detailed description of the interiors of stars. Some general features of stellar structure can be discovered through these solutions. The mass distribution indicates that for high-mass stars with M ≥ 1. 2 M⊙ over 95 % of the mass is contained within ∼ 60 % of the radius.
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Main sequence abundances: Observational aspects
International Astronomical Union Colloquium, 1988AbstractAlthough once it was thought that main-sequence stars are remarkably homogeneous with respect to their chemical composition, the upper main-sequence stars (30000 > Te > 7000) show a variaety of chemically peculiar stars besides the so-called normal stars. Those include the Am, Ap, λ Bootis, He-deficient, and He-rich stars.
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2012
In the last section we left the newly born star while it was still contracting in hydrostatic, but not yet thermal, equilibrium. Essential features of this contraction can already be understood by assuming simple homologous changes. It will turn out that the fate of such a sphere is mainly determined by the equation of state.
Rudolf Kippenhahn +2 more
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In the last section we left the newly born star while it was still contracting in hydrostatic, but not yet thermal, equilibrium. Essential features of this contraction can already be understood by assuming simple homologous changes. It will turn out that the fate of such a sphere is mainly determined by the equation of state.
Rudolf Kippenhahn +2 more
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1987
The IUE satellite has inaugurated a new era in the study of pre-main sequence (PMS) objects. IUE observations have revealed not just a new wavelength range but also a new temperature regime embracing physical phenomena that could not be studied before.
Catherine L. Imhoff, I. Appenzeller
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The IUE satellite has inaugurated a new era in the study of pre-main sequence (PMS) objects. IUE observations have revealed not just a new wavelength range but also a new temperature regime embracing physical phenomena that could not be studied before.
Catherine L. Imhoff, I. Appenzeller
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Cancer epigenetics in clinical practice
Ca-A Cancer Journal for Clinicians, 2023Veronica Davalos, Manel Esteller
exaly
2015
In this final chapter we focus on binary populations amongst pre-main-sequence stars, namely the evolutionary phase between protostars and the main-sequence which includes both classical and weak-lined T Tauri stars. Our discussion begins by looking at the frequency of pre-main-sequence binaries as a function of environment as well as orbital period ...
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In this final chapter we focus on binary populations amongst pre-main-sequence stars, namely the evolutionary phase between protostars and the main-sequence which includes both classical and weak-lined T Tauri stars. Our discussion begins by looking at the frequency of pre-main-sequence binaries as a function of environment as well as orbital period ...
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2011
The time for the completion of protostellar evolution is effectively 2–3 times the free-fall time of the outer layers, which lies in the range 105–106 yr, depending on the initial density. As the accretion rate tapers off in the later phases and the infalling envelope becomes less and less opaque, the observable surface of the protostar declines in ...
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The time for the completion of protostellar evolution is effectively 2–3 times the free-fall time of the outer layers, which lies in the range 105–106 yr, depending on the initial density. As the accretion rate tapers off in the later phases and the infalling envelope becomes less and less opaque, the observable surface of the protostar declines in ...
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Stellar Evolution and Nucleosynthesis: Main Sequence and Post Main Sequence
This thesis explores post-MS nuclear reactions, including triple-alpha capture and the “holy grail,” focusing on reaction rate calculations. Additionally, we analyze stellar surveys (GAIA, SDSS, HIPPARCOS) to construct color-magnitude diagrams and track stellar evolution. By studying stellar clusters, we identify coeval stars and MS turnoff points.openaire +1 more source
1988
The observational work which has been done to date on young low-mass binaries is reviewed. Much effort is currently put into surveys of such binaries, and results from - as well as some limitations of - various techniques are discussed. Statistical analysis of a sufficiently large sample of pre-main sequence binaries will eventually provide essential ...
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The observational work which has been done to date on young low-mass binaries is reviewed. Much effort is currently put into surveys of such binaries, and results from - as well as some limitations of - various techniques are discussed. Statistical analysis of a sufficiently large sample of pre-main sequence binaries will eventually provide essential ...
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