https://doi.org/10.1140/epjd/e2005-00051-7
Gas kinetic studies using a table-top set-up with electron beam excitation: quenching of molecular nitrogen emission by water vapour
1
Fakultät für Physik E12, Technische Universität
München, 85748 Garching, Germany
2
TuiLaser, Industriestr. 15, 82110 Germering, Germany
Corresponding author: a Andreas.Ulrich@ph.tum.de
Received:
19
January
2005
Revised:
23
February
2005
Published online:
26
April
2005
A table-top set-up for studying gas kinetic processes in dense gases via time
resolved optical spectroscopy is presented. The set-up uses low energy
electron beams for gas excitation. A thin silicon nitride membrane
separating the electron source and the gas cell allows to use electron
energies as low as 10–15 keV. The electron source is operated in a fast
pulsing mode with a pulse width of 5 ns and repetition rates up to 30 kHz.
Light emission from the target gas sample is studied and time resolved
photon counting is used to measure decay times and collisional rate
constants for specific excited states. The experimental concept is applied
to measure the rate constants for quenching of molecular nitrogen in the C
state (vibrational levels 0 and 1) by water vapour.
Quenching rate constants of (
) × 10
s
cm3 and
(
) × 10-10 s-1 cm3 were obtained for the C (v = 0) and C
(v = 1) vibrational levels, respectively.
PACS: 34.80.Dp – Atomic excitation and ionization by electron impact / 34.80.Gs – Molecular excitation and ionization by electron impact / 33.50.Hv – Radiationless transitions, quenching
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005
