Results 311 to 320 of about 220,237 (344)

Inferred properties of stellar granulation

Publications of the Astronomical Society of the Pacific, 1985
Apparent characteristics of stellar granulation in F and G main-sequence stars are inferred directly from observed spectral-line asymmetries and from comparisons of numerical simulations with the observations: (1) the apparent granulation velocity increases with increasing effective temperature, (2) the dispersion of granule velocities about their mean
D. F. Gray, C. G. Toner
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Stellar Convection; General Properties

1997
We review the properties of stellar convection zones, in particular with respect to issues of relevance to helio- and astero-seismology. Convection is responsible both for establishing the one-dimensional average structure on top of which the waves are propagating and for maintaining large amplitude three-dimensional fluctuations that interact with the
Åke Nordlund, Bob Stein
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Properties of Knots in Cooling Stellar Jets

Astrophysics and Space Science, 2004
Modelling the formation of the maximal emission regions in Herbig-Haro flows, the socalled ‘knots,’ remains a main challenge in the investigation of the YSO’s outflows. Recent HST images of optical regions reveal their wide morphological variety. Knotty structures and arc-like regions coexist, suggesting that several mechanisms could be responsible for
RUBINI, FRANCESCO MARIO, C. Giovanardi, S. Lorusso, F. Leeuwin, F. Bacciotti   +4 more
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Properties of nonradial stellar oscillations

2008
It is shown that the oscillatory properties of the eigenfunctions can be proved rigorously for the second order problem. Models with discontinuities in density are also considered and “discontinuity modes” are shown to exist. The distribution of amplitudes of these modes is also discussed.
M. Gabriel, R. Scuflaire
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Stellar properties and spectra

2011
Stars exist in great variety. They are among the most stable, as well as occasionally the most unstable, objects in the Universe. While extremely massive stars have short but very active lifetimes of only millions of years after birth, the oldest stars have estimated ages of up to 14 billion years at the present epoch, not much shorter (though it must ...
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Measuring Other Stellar Properties

2012
The distance to nearby stars can be measured through geometrical methods. When the distance is known, additional observations of the spectra of stars and light curves of binary systems allow us to determine the temperatures, sizes, and luminosities of many nearby stars. In this way we can find correlations between different stellar properties and begin
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Statistical Properties of Stellar Speckle Patterns

2015
This chapter examines the statistical properties of speckle patterns—stellar speckle patterns—formed in short-exposure star images. Expressions are developed for the probability density functions of the amplitude, phase, complex amplitude, and intensity in these patterns.
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Stellar Properties of OH/IR Stars

1987
The rapid accumulation of data makes it possible to begin to determine the positions of OH/IR stars on the mass-luminosity plane. With the assumption of fundamental mode pulsation, the accurately determined period-luminosity-color relationships in the Mira region will be extrapolated to the larger OH/IR region, where the Mira variables have evolved. OH/
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Some properties of static general relativistic stellar models. II

Journal of Mathematical Physics, 1980
We expand here the study of the type of identity which has been successfully used to prove the necessity of spherical symmetry in static black holes and uniform density stellar models. We show how the system of partial differential equations, whose solutions correspond to these identities, can be decoupled and partially integrated for fluids with an ...
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Properties of matter in stellar collapse

2006
A brief review is given of the properties of matter in collapsing stars, with particular emphasis on the properties of nuclei.
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