Emission spectra of a pulse needle-to-plane corona-like discharge in conductive aqueous solution

0381679 - ÚFP 2013 RIV GB eng J - Journal Article
Šimek, Milan - Člupek, Martin - Babický, Václav - Lukeš, Petr - Šunka, Pavel
Emission spectra of a pulse needle-to-plane corona-like discharge in conductive aqueous solution.
Plasma Sources Science & Technology. Roč. 21, č. 5 (2012), 055031-055031. ISSN 0963-0252. E-ISSN 1361-6595
R&D Projects: GA AV ČR IAAX00430802
Institutional research plan: CEZ:AV0Z20430508
Keywords : Water * pulsed electrical breakdown * point-plane geometry * streamer propagation * corona discharge * emission spectroscopy
Subject RIV: BL - Plasma and Gas Discharge Physics
Impact factor: 2.515, year: 2012
http://iopscience.iop.org/0963-0252/21/5/055031/pdf/0963-0252_21_5_055031.pdf

We explored basic optical and electrical characteristics of a positive corona-like discharge produced in conductive aqueous solutions by periodic high-voltage pulses. Emission spectra of the discharge were acquired in a needle-to-plate electrode geometry and analyzed in the UV-vis-NIR spectral range with nanosecond time resolution for the solution conductivity of 100 and 500 mS/cm. The most important emission features are due to electronic excitation of HI, OI, OII and OH species. We have found evidence of significant time-dependent line-shape broadening of selected HI and OI transitions. The observed broadening is attributed to the dynamic Stark and pressure broadening mechanisms and significantly increases with the aqueous solution conductivity. Electron densities were estimated by fitting a single Voigt peak function to observed Hđ profiles, and reach as much as ne 4x1018 cm-3 (tD = 300 ns at 100 mS/cm solution) and ne 51018 cm-3 (tD = 1 ms at 500 mS/cm). Temporal evolution of the partially-resolved rotational structure of the OH emission reaches a maximum during the discharge decay, with the onset significantly delayed with respect to the streamer ignition.
Permanent Link: http://hdl.handle.net/11104/0212094