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星期二, 七月 17, 2007

Grrasberg 1971 超新星光变曲线理论

主要内容:
从俄文翻译为英文的。数值模拟爆发的动力学(激波)和辐射转移(在氢包层中),以及核合成。

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文章信息:

Title:
On the Theory of the Light Curves of Supernovate
Authors:
Grrasberg, E. K.; Imshenik, V. S.; Nadyozhin, D. K.
Publication:
Astrophysics and Space Science, Vol. 10, p.28 (Ap&SS Homepage)
Publication Date:
00/1971

Abstract

An account of the theory of the light curves of supernovae is presented, based on certain assumptions concerning the passage through the stellar atmosphere of powerful shock waves. The investigation is based on numerical integration of appropriate equations of gas dynamics and radiative heat-conductivity. The calculations substantially involve the ionization and recombination of hydrogen in the envelope of a supernova. Changes are traced in the curves arising from the tran- sition from compact stars with small radius (`~` 10 R®), to stars with very extensive envelopes (`S.' 10000 R0). The light curves for compact stars agree well with observations of the peculiar supernovae in NGC 5457, NGC 6946 and NGC 5236. The characteristics of the light curves with the passage of shock waves through the extended atmosphere coincide within an order of magnitude with observations of the supernovae of type II and type I near their maximum brightness. A powerful heat-wave propagates before the shock-front in the extensive atmosphere which gives rise to a detached supernova envelope in the form of a thin spherical layer. We investigated the condition in an ascending wave of cooling and recombination in the supernova envelope. It is shown that part of the hydrogen may recombine to attain full transparency for radiation passing through it. The ob- servations are compared with the results of the theory of radioactive decay of the elements. This explanation of the light curves by the passage of shock waves requires energies of 1050 to 1052 ergs, which are in agreement with mechanisms of thermonuclear explosions

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