Measurement of quenching coefficients and development of calibration methods for quantitative spectroscopy of plasmas at elevated pressures

Anne Francis; Timo Gans; Kari Niemi; U. Czarnetzki; Volker Schulz-von der Gathen; H. F. Dobele

doi:10.1117/12.459391

19 March 2002 Measurement of quenching coefficients and development of calibration methods for quantitative spectroscopy of plasmas at elevated pressures

Anne Francis, Timo Gans, Kari Niemi, U. Czarnetzki, Volker Schulz-von der Gathen, H. F. Dobele

Author Affiliations +

Proceedings Volume 4460, Selected Research Papers on Spectroscopy of Nonequilibrium Plasma at Elevated Pressures; (2002) https://doi.org/10.1117/12.459391
Event: Selected Research Papers on Spectroscopy of Nonequilibrium Plasma at Elevated Pressures, 2002, Moscow, Russian Federation

Abstract

Measurements of collisional de-excitation (quenching) coefficients required for the interpretation of emission and fluorescence spectroscopic measurements are reported. Particular attention is turned on argon transitions which are of interest for actinometric determinations of atomic ground state populations and on fluorescence lines originating from excited atoms and noble gases in connection with two-photon excitation (TALIF) of atomic radicals. A novel method is described which allows to infer quenching coefficients for collisions with molecular hydrogen of noble gas states in the energy range up to 24 eV. The excitation is performed in these experiments by collisions of energetic electrons in the sheath of an RF excited hydrogen plasma during the field reversal phase which lasts about 10 ns. We describe in addition a calibration method -including quenching effectsf o-r the determination by TALIF of absolute atomic radical densities of hydrogen, nitrogen and oxygen using two-photon resonances in noble gases close by the resonances of the species mentioned. The paper closes with first ideas on a novel technique to bypass quenching effects in TALIF by introducing an additional, controllable loss by photoionization that will allow quenching-free determination of absolute atomic densities with prevalent nanosecond laser systems in situations where collisional de-excitation dominates over spontaneous emission.

Citation Download Citation

Anne Francis, Timo Gans, Kari Niemi, U. Czarnetzki, Volker Schulz-von der Gathen, and H. F. Dobele "Measurement of quenching coefficients and development of calibration methods for quantitative spectroscopy of plasmas at elevated pressures", Proc. SPIE 4460, Selected Research Papers on Spectroscopy of Nonequilibrium Plasma at Elevated Pressures, (19 March 2002); https://doi.org/10.1117/12.459391

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available