Measurements of N2(A) by pulsed cavity ringdown spectroscopy in repetitively pulsed nanosecond discharges
Janda M., Stancu G.D., Spence T.G., Harb C., Kaddouri F., Pai D., Lacoste D., Laux C.O. XVII International Conference on Gas Discharges and their Applications, Cardiff, UK, September 7-12, p. 385-388 (2008)
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Abstract: We present here results from the measurements of metastable N2(A)
species in nanosecond repetitively pulsed (NRPP) discharge obtained
by using pulsed cavity ringdown spectroscopy (CRDS) at 770 nm.
The NRPP was generated in a pin-to-pin electrode configuration
in atmospheric pressure preheated air or nitrogen (300-1000 K)
by 10 ns short high voltage pulses (5-8 kV) at high frequency (2-30 kHz),
air flow rate from 1 to17 m/s and gap distance 1-7 mm.
Despite the small plasma volume (1-10 mm3) and short lifetime of
studied plasma species (tens of nanoseconds), the CRDS allowed us
to obtain spectra with spectral resolution down to 1 pm, time
resolution down to 100 ns and according to our preliminary results
with the detection limit below 1 ppmv. Obtained results were also
used for the validation of kinetic model, which already showed good
agreement with results from the measurements of spatial and time
evolution of other the excited state species N2(B), N2(C), N2+(B), NO(A)
and O(3p 5P) obtained using intensity calibrated emission spectroscopy.
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