Basic concepts of temperature determination from self-reversed spectral lines

Abstract

Complex high-pressure plasmas have become increasingly important in technical applications such as high-intensity discharge lamps. The knowledge of temperature distributions is of basic interest for the understanding of the physical mechanisms in these plasmas and for a selective manipulation of their properties. It is shown that self-reversed spectral lines provide a powerful diagnostic tool for temperature determination. The two most important approaches for the corresponding data analysis are reviewed and their limitations are discussed. On the basis of these approaches a new method is proposed which avoids the main limitations especially in the application to resonance lines. The temperature has been determined in a Hg/Ar and a Hg/Ar/TlI high-pressure discharge. Measured spectral radiances of the Hg 546.1 and 253.7 nm as well as Tl 377.6 nm lines are analysed and the potentials of the different methods are demonstrated.

Determining the arc temperature in submerged arc welding using the Bartels method

“…The reason is that the measurements take place in the middle of the arc column where we can assume a collision-dominated plasma in LTE. Also, Schneidenbach [25] and Kettlitz [26] used this method for the confined plasma in HID lamps and determining the temperature with Hg and Tl lines. In the case of SAW, the confinement takes place via the flux, which physically limits the plasma, and the analyzed element is Mg.…”

Mercury-free high pressure discharge lamps dominated by molecular radiation

“…This line is often used to determine the radial temperature profile of Tl-containing discharges via the Bartels method [12]. For the purpose of the following discussion it should be kept in mind that the intensity of this line's self-reversal shoulders is proportional to the maximum temperature met along the line-of-sight.…”

Self-Reversed Scandium Lines as a Diagnostic Tool for Multicomponent HID Lamps

“…The purpose of this work is to analyze the capability of self-reversed scandium lines to determine the radial temperature profile using Bartels method [Bartels 1950a, Bartels 1950b, Schneidenbach and Franke 2008.…”