Journal or Publication Title:

Բյուրականի աստղադիտարանի հաղորդումներ: Երևանի աստղադիտարանի բյուլետեն = Сообщения Бюраканской обсерватории. Бюллетень ереванской Астрономической обсерватории = Contributions from the Burakan observatory. Bulletin of the Erevan astronomical observatory

Date of publication:

2025

Volume:

72

Number:

1

ISSN:

2579-2276

Coverage:

106-112

Abstract:

As part of our recent series of works on the evolution of spectral lines formed in optically active media under the influence of non-stationary energy sources, the paper examines temporal changes in certain statistical averages characterising the radiation field in the medium under study. Line radiation transfer in 1D atmosphere of finite optical thickness is considered for monochromatic scattering. Of the statistical averages, the greatest attention is paid to the average residence time of various photons during diffusion in the medium. At the same time, the average number of scatterings occurring in the medium and the average number of photons undergoing thermalization are also determined. The specified values, together with the profiles of the lines formed, are given for both photons reflected from the medium and photons passing through it. First, the problem of steady-state radiation is considered, after which the evolutionary picture of all the above-mentioned values under the action of non-stationary sources of illumination of the medium is described.

Format:

pdf

Identifier:

oai:arar.sci.am:425921

General note:

Communications of the Byurakan Astrophysical Observatory (ComBAO) is a peer-reviewed scientific journal, which publishes research in observational and theoretical astronomy/astrophysics and presents recent advances in these fields. It is being published by the NAS RA V. Ambartsumian Byurakan Astrophysical Observatory (BAO) in English in electronic form. The journal publishes original papers, review papers, brief reports, book reviews, special communications, observational and theoretical results in various fields of astronomy and related sciences, and some editorial notes, including anniversaries and obituaries. Under the heading “Legacy”, the renewed magazine will republish some old articles of high value in English. The heading “Guest articles” will bring to the attention of readers the articles of researchers who are not employees of BAO. ComBAO was founded in 1946 and regularly published in 1946-1990. However, the publication was interrupted because of the economic situation after the disintegration of the Soviet Union in 1991.

Location of original object:

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