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arXiv · 1501.00782

Experimental study on hard X-rays emitted from metre-scale negative discharges in air

P. O. Kochkin·A. P. J. van Deursen·Ute Ebert
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Abstract

We investigate the development of meter long negative discharges and focus on their X-ray emissions. We describe appearance, timing and spatial distribution of the X-rays. They appear in bursts of nanosecond duration mostly in the cathode area. The spectrum can be characterized by an exponential function with 200 keV characteristic photon energy. With nanosecond-fast photography we took detailed images of the pre-breakdown phenomena during the time when X-rays were registered. We found bipolar discharge structures, also called "pilot systems", in the vicinity of the cathode. As in our previous study of X-rays from positive discharges, we correlate the X-ray emission with encounters between positive and negative streamers. We suggest that a similar process is responsible for X-rays generated by lightning leaders.

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P. O. Kochkin, A. P. J. van Deursen, Ute Ebert. 2015-01-05. Experimental study on hard X-rays emitted from metre-scale negative discharges in air. https://doi.org/10.1088/0022-3727%2F48%2F2%2F025205

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