Spectral-Line Intensity and Spatial Source Inhomogeneity

  • P. W. J. M. Boumans


When discussing in the previous chapter the dependence of spectral-line intensity on temperature and electron pressure we tacitly assumed the source to be homogeneous. In fact, as we mentioned in § 3.8 and found in §§ 6.12 to 6.16, we must consider radial distributions in an arc. In this chapter we shall attempt to incorporate the radial decline of temperature (T) and electron pressure (P e ) into our picture of line intensities. We shall resort to a model that approximates the actual conditions well enough to permit conclusions which have general validity. Interestingly, our calculations, which were made for instruction purposes, yield some remarkable results which enable us to define the scope of the effective values of temperature and electron pressure. We shall demonstrate in subsequent sections that a slice of plasma through the arc can be approximated, with respect to the emission of spectral lines, by a circular disk of effective temperature \(\hat{T}\), of effective electron pressure \({{\hat{p}}_{e}}\) and of effective radius\(\hat{R}\). This holds for all ion lines and for most atom lines except the low-level lines of elements with a low ionization potential.


Effective Temperature Atom Line Line Pair Electron Pressure Excitation Potential 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© P. W. J. M. Boumans 1966

Authors and Affiliations

  • P. W. J. M. Boumans
    • 1
  1. 1.Laboratory for Analytical ChemistryUniversity of AmsterdamThe Netherlands

Personalised recommendations