Publication details

Emerging and expanding streamer head in low-pressure air

Authors

HODER Tomáš BONAVENTURA Zdeněk PRUKNER V. GORDILLO-VAZQUEZ F.J. SIMEK M.

Year of publication 2020
Type Article in Periodical
Magazine / Source PLASMA SOURCES SCIENCE & TECHNOLOGY
MU Faculty or unit

Faculty of Science

Citation
Web http://dx.doi.org/10.1088/1361-6595/ab7087
Doi http://dx.doi.org/10.1088/1361-6595/ab7087
Keywords streamer; electric field; low-pressure air; electron density; blue jet; transient luminous events; ionisation wave
Description The emergence of a streamer from an ionisation wave and its expansion are ultra-fast processes shaping the very first moments of the streamer development, and are usually accessible only by complex numerical models. In this Letter, we report experimental evidence of the emergence of a streamer from an ionisation wave in 1.3 kPa air, a laboratory analogue of early-stage streamers emerging in geophysical Blue Starters and Jets. The radially and temporally resolved electric field patterns of an expanding streamer are determined by sub-nanosecond optical emission spectroscopy. As the emerged streamer expands, the electric field decreases by a factor of 1.4 in 1 ns. We quantify the radial expansion of the streamer head and its axial acceleration, reaching the velocity of 10(7) m s(-1). In combination with electrical measurements, the transferred charge, electron density, and mean electron energy are quantified, enabling detailed insight into this ultra-fast phenomenon at its characteristic time-scale.
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