open access

https://hdl.handle.net/2115/86325

Estimation of Vibrational Temperatures of N-2 and CO2 in Low-Pressure Electron Cyclotron Resonance Plasmas by Threshold Ionization Mass Spectrometry

英語

low-pressure plasma

2022-07-15

The Japan Society of Plasma Science and Nuclear Fusion Research

Plasma and Fusion Research

17

1406070

This paper demonstrates the estimation of vibrational temperatures of N-2 and CO2 in low-pressure plasmas by threshold ionization mass spectrometry. The principle for the estimation is the decrease in the ionization potential by the vibrational excitation. We observed that the threshold ionization curves of N-2 and CO2, which were measured using a quadrupole mass spectrometer with an energy-variable electron beam, shifted toward the low-energy side, when they were sampled from the plasmas. We constructed a model which assumed a Boltzmann distribution for the population densities of vibrational excited states and the same cross sections of electron impact ionization for vibrational excited states except the shifts of the threshold energies. The vibrational temperatures were estimated by fitting the experimental threshold ionization curves with the model.

学術雑誌論文

Version of Record

1880-6821