Results 251 to 260 of about 1,827 (268)

Nonradial and nonlinear stellar pulsation

Nature, 1979
D. Gough
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Stellar Pulsations and Stability

2002
Being a dynamical system, the star has diverse oscillatory eigenmodes. When one takes thermal processes into account, some of these appear to be unstable. The increment of such an instability γ, equal to the inverse time scale of the amplitude increase by a factor of e, is usually well below the pulsational frequency ω.
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Relativistic Stellar Pulsations

1987
This thesis consists of studies on the topic of relativistic stellar pulsations. i) A new formalism for the numerical study of g-modes in neutron stars is developed. This formalism avoids pitfalls associated with previous formalisms when applied to the study of these low-frequency modes.
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The development of the theory of stellar pulsations

Vistas in Astronomy, 1997
Abstract A short account is presented of the struggle to understand and provide a theory for stellar pulsations. The observational and theoretical developments from the discovery of δ Cephei in 1784 up to Baker and Kippenhahn's key paper of 1962 are described and their significance discussed.
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Inversion method in stellar pulsation

AIP Conference Proceedings, 2007
This is a presentation of the asteroseismological method (ROMOSC) implemented in the Bucharest Observatory to be used in the CoRoT mission. We will also present a calibration of this method with the similar one implemented in the MOST mission in the case of the star η Boo.
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Physical mechanisms in stellar pulsations

The Journal of the Acoustical Society of America, 1985
Stars evolve from their births to their deaths by converting their store of hydrogen to helium, and then much of this helium is fused to heavier elements such as carbon, oxygen, and up to iron. During this evolution, the stellar mass may decrease by a stellar wind mass loss, the radius usually greatly increases, and the radiation luminosity emitted at ...
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A Perturbative Approach to Stellar Pulsations [PDF]

, 1985
An asymptotic perturbation formalism is adapted to the problem of the nonlinear behavior of stellar pulsators. It leads to amplitude equations which govern the temporal, regular or chaotic modulations of the amplitudes of the excited modes. These amplitude equations have been calculated and solved for realistic population I (Classical) Cepheid models ...
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The Model-Oscillators of Stellar Pulsation

2001
The recent works on the model-oscillators of stellar pulsation in relation to the nonlinear dynamics are reviewed. We first summarize nonlinear equations with nonlinear terms which cause irregular and chaotic oscillations. The Lorenz equation and its family are described.
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Basic Aspects of Stellar Structure and Pulsation

2000
The purpose of this chapter is to provide a general background for the more specific chapters to follow. Much of the application of variability in astrophysics is concerned with stellar structure; thus we briefly review the calculation of stellar structure and evolution. Furthermore, we present the ‘machinery’ of stellar pulsations.
Christensen-Dalsgaard, J., Dziembowski, W.A.   +1 more
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The Modelling of Nonlinear Stellar Pulsations

1990
A brief introduction to stellar pulsations and a discussion of some of the physical problems facing the investigator are presented. Then the achievements and remaining difficulties of the numerical modelling of the linear and nonlinear properties of the pulsations are summarized. We conclude with desiderata for an ideal code.
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