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Meccanica

, Volume 5, Issue 3, pp 197–202 | Cite as

Line radiation in non local thermodynamic equilibrium

  • Massimo Germano
Article
  • 20 Downloads

Summary

This paper deals with the problem of line radiation in conditions of non thermodynamic equilibrium and applies the results obtained to the study of the imprisonment of resonance radiation. It was found that the excited level, and by consequence the resonance radiation, decays in two ways in competition each other: one is a diffusive decay, due to the fact that the gas is generally very thick for frequencies near the center of the absorption line, and the other is an exponential decay due to the far “wings” of the absorption coefficient, where the gas is optically thin.

Keywords

Radiation Absorption Coefficient Mechanical Engineer Civil Engineer Allo 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Sommario

E' stata trattata la radiazione di linea in condizioni di non equilibrio termodinamico, e i risultati ottenuti sono stati applicati allo studio del cosiddetto “intrappolamento” della radiazione risonante. S'è trovato che il livello eccitato, e di conseguenza la radiazione risonante, decade in due modi in competizione fra loro: il primo è un decadimento di tipo diffusivo, ed è dovuto al fatto che il gas è generalmente otticamente opaco al centro della linea di assorbimento, mentre il secondo è di tipo esponenziale, ed è dovuto alle “code” del coefficiente di assorbimento, dove il gas è otticamente sottile.

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Copyright information

© Tamburini Editore s.p.a. Milano 1966

Authors and Affiliations

  • Massimo Germano
    • 1
  1. 1.Istituto di Meccanica ApplicataPolitecnico di TorinoItaly

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