TY - JOUR
T1 - Time-resolved absolute OH density of a nanosecond pulsed discharge in atmospheric pressure He-H2O
T2 - Absolute calibration, collisional quenching and the importance of charged species in OH production
AU - Verreycken, T.
AU - Sadeghi, N.
AU - Bruggeman, P. J.
PY - 2014/8
Y1 - 2014/8
N2 - The time-resolved OH density in a nanosecond pulsed filamentary discharge in an atmospheric pressure He-H2O(0.05%) mixture is measured using laser induced fluorescence. The lifetime of the excited OH(A) state is found to be strongly time dependent during the plasma pulse, with the shortest decay time occurring at the moment the plasma is switched off. The measured LIF intensity is corrected for this time-resolved quenching and calibrated using Rayleigh scattering. Time-resolved electron density , He (3S1) metastable density , gas temperature and optical emission are presented and used in the interpretation of the observed time dependence of the OH density. Based on these experimental data, it is shown that for the present discharge conditions, OH is mainly produced by charge transfer reactions to water followed by dissociative recombination of the water ion. In addition, two often encountered issues with the calibration of OH LIF are highlighted with an example.
AB - The time-resolved OH density in a nanosecond pulsed filamentary discharge in an atmospheric pressure He-H2O(0.05%) mixture is measured using laser induced fluorescence. The lifetime of the excited OH(A) state is found to be strongly time dependent during the plasma pulse, with the shortest decay time occurring at the moment the plasma is switched off. The measured LIF intensity is corrected for this time-resolved quenching and calibrated using Rayleigh scattering. Time-resolved electron density , He (3S1) metastable density , gas temperature and optical emission are presented and used in the interpretation of the observed time dependence of the OH density. Based on these experimental data, it is shown that for the present discharge conditions, OH is mainly produced by charge transfer reactions to water followed by dissociative recombination of the water ion. In addition, two often encountered issues with the calibration of OH LIF are highlighted with an example.
KW - OH density calibration
KW - OH dynamics
KW - nanosecond pulsed discharge
UR - http://www.scopus.com/inward/record.url?scp=84902841567&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84902841567&partnerID=8YFLogxK
U2 - 10.1088/0963-0252/23/4/045005
DO - 10.1088/0963-0252/23/4/045005
M3 - Article
AN - SCOPUS:84902841567
SN - 0963-0252
VL - 23
JO - Plasma Sources Science and Technology
JF - Plasma Sources Science and Technology
IS - 4
M1 - 045005
ER -