Measurement of the electric field distribution in streamer discharges

TL;DR

This study employs electric field induced second harmonic generation (E-FISH) to measure the electric field distribution in streamer discharges with high spatial and temporal resolution, validating results against simulations and demonstrating E-FISH's applicability to large streamer sizes.

Contribution

First application of E-FISH to large streamer discharges over a large gap, with a developed deconvolution method for absolute electric field measurement.

Findings

Good agreement between measured and simulated electric fields.

Successful high-resolution measurements of streamer electric fields.

Demonstrated E-FISH's potential for complex electric field distributions.

Abstract

Using electric field induced second harmonic generation (E-FISH), we performed direction-resolved absolute electric field measurements on single-channel streamer discharges in 70 mbar (7 kPa) air with 0.2 mm and 2 ns resolutions. In order to obtain the absolute (local) electric field, we developed a deconvolution method taking into account the phase variations of E-FISH. The acquired field distribution shows good agreement with the simulation results under the same conditions, in direction, magnitude and in shape. This is the first time that E-FISH is applied to streamers of this size (> 0.5cm radius), crossing a large gap. Achieving these high resolution electric field measurements benefits further understanding of streamer discharges and enables future use of E-FISH on cylindrically symmetric (transient) electric field distributions.