Книга: Andri Prozesky «Atomic processes in gaseous nebulae»
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Производитель: "LAP Lambert Academic Publishing" The modelling of the population structure of the hydrogen atom in a nebula under non-thermal equilibrium conditions is essential to interpret spectral lines from the gas. Stimulated processes become increasingly important as the frequency of radiation emitted by atomic transitions decreases, and it is important to include these processes when studying radio recombination lines. In this study, the influence of stimulated processes on the departure coefficients of the n-levels of hydrogen was investigated. A full quantum mechanical treatment was used where possible to calculate the rates of atomic processes, so that the atomic data is very accurate. It was found that the ionizing radiation from a nearby star and the CMBR can have a significant effect on the population of levels with large principal quantum numbers. The validity of the Case B approximation, in which Lyman transitions are assumed to be optically thick, was investigated. It was found that Case B is valid even for... ISBN:9783659180934 Издательство: "LAP Lambert Academic Publishing" (2012)
ISBN: 9783659180934 |
См. также в других словарях:
nebula — nebular, adj. /neb yeuh leuh/, n., pl. nebulae / lee , luy /, nebulas. 1. Astron. a. Also called diffuse nebula. a cloud of interstellar gas and dust. Cf. dark nebula, emission nebula, reflection nebula … Universalium
chemical element — Introduction also called element, any substance that cannot be decomposed into simpler substances by ordinary chemical processes. Elements are the fundamental materials of which all matter is composed. This article considers the… … Universalium
galaxy — /gal euhk see/, n., pl. galaxies. 1. Astron. a. a large system of stars held together by mutual gravitation and isolated from similar systems by vast regions of space. b. (usually cap.) See Milky Way. 2. any large and brilliant or impressive… … Universalium
Theoretical astronomy — Nucleosynthesis Stellar nucleosynthesis Big Bang nucleosynthesis Supernova nucleosynthesis Cosmic ray spallation … Wikipedia
cosmos — /koz meuhs, mohs/, n., pl. cosmos, cosmoses for 2, 4. 1. the world or universe regarded as an orderly, harmonious system. 2. a complete, orderly, harmonious system. 3. order; harmony. 4. any composite plant of the genus Cosmos, of tropical… … Universalium
star — starless, adj. /stahr/, n., adj., v., starred, starring. n. 1. any of the heavenly bodies, except the moon, appearing as fixed luminous points in the sky at night. 2. Astron. any of the large, self luminous, heavenly bodies, as the sun, Polaris,… … Universalium
