Galactic models with variable spiral structure
نویسندگان
چکیده
منابع مشابه
Galactic spiral structure
We describe the structure and composition of six major stellar streams in a population of 20 574 local stars in the New Hipparcos Reduction with known radial velocities. We find that, once fast moving stars are excluded, almost all stars belong to one of these streams. The results of our investigation have led us to re-examine the hydrogen maps of the Milky Way, from which we identify the possi...
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Using one-dimensional hydrodynamic simulations including interstellar heating, cooling, and thermal conduction, we investigate nonlinear evolution of gas flow across galactic spiral arms. We model the gas as a non-self-gravitating, unmagnetized fluid, and follow its interaction with a stellar spiral potential in a local frame comoving with the stellar pattern. Initially uniform gas with density...
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Introduction: In the original variable-density (VD) spiral trajectory[1], the sampling density varies throughout the k-space trajectory; i.e., k(τ) = λτe , where the parameter α controls the rate of density variation. Here, we propose a k-space trajectory consisting of an Archimedean spiral[2] from the origin out to a given radius k1, and extending beyond k1 with a variable-density spiral of α>...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1978
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/182.3.331