Runaway electrons and x-ray emission in air and other gases during discharges with long rise time of voltage pulses

The objective of the work is to study effect of the rise time of voltage pulses ranged from 15 ns to 1.5 μs on generation of runaway electron beams and X-ray radiation in nonuniform electric field. Three setups and different pressures of air, nitrogen, argon and helium were used. The experiments on the setup #1 have confirm that there are different regimes of generation of runaway electrons and X-ray emission when voltage pulses with a long front duration are used. When voltage pulse amplitude reached 150 kV at a pulse rise time of 1.5 μs, the new results was obtained on the setup #3. At this setup, a runaway electron beam was registered by a collector in argon, air, and nitrogen at pressures up to ≈ 12.5 kPa. When using helium, a supershort avalanches electron beam (SAEB) was obtained at a pressure of 100 kPa.

[1]  J. Kim,et al.  RELEC mission: Relativistic electron precipitation and TLE study on-board small spacecraft , 2016 .

[2]  Cheng Zhang,et al.  Measurement of runaway electron beam current in nanosecond-pulse discharges by a Faraday cup , 2018, Laser and Particle Beams.

[3]  Cheng Zhang,et al.  X-ray radiation and runaway electron beams generated during discharges in atmospheric-pressure air at rise times of voltage pulse of 500 and 50 ns , 2018, Laser and Particle Beams.

[4]  Vladimir A. Rakov,et al.  A study of X-ray emission from laboratory sparks in air at atmospheric pressure , 2008 .

[5]  V. Tarasenko,et al.  Generation of runaway electrons and X rays in an inhomogeneous electric field at high gas pressures , 2016 .

[6]  E. H. Baksht,et al.  Runaway electrons preionized diffuse discharges at high pressure , 2009, 2010 Abstracts IEEE International Conference on Plasma Science.

[7]  V. Tarasenko,et al.  Two-component structure of the current pulse of a ranaway electron beam generated during electric breakdown of elevated-pressure nitrogen , 2012 .

[8]  V. Tarasenko,et al.  Generation of dual pulses of the runaway electron beam current during the subnanosecond breakdown of atomic and molecular gases , 2016 .

[9]  S. Brezinsek,et al.  Overview of wall probes for erosion and deposition studies in the TEXTOR tokamak , 2017 .

[10]  Cheng Zhang,et al.  Runaway electrons and x-rays from a corona discharge in atmospheric pressure air , 2011 .

[11]  N. Babaeva,et al.  Subnanosecond breakdown in high-pressure gases , 2018 .

[12]  Vasilii Ripenko,et al.  Microstructure of copper surface treated by runaway electron preionized diffuse discharge in atmospheric pressure nitrogen stream , 2018, Atomic and Molecular Pulsed Lasers.

[13]  V. Tarasenko,et al.  Generation of supershort avalanche electron beams and formation of diffuse discharges in different gases at high pressure , 2008 .

[14]  V. Pasko.  Blue jets and gigantic jets: transient luminous events between thunderstorm tops and the lower ionosphere , 2008 .

[15]  Viktor F Tarasenko,et al.  Efficient gas lasers pumped by run-away electron preionized diffuse discharge , 2015, International Symposium on High Power Laser Systems and Applications.

[16]  Joan Montanyà,et al.  Influence of the voltage‐time derivative in X‐ray emission from laboratory sparks , 2010 .

[17]  M. Yalandin,et al.  Energy compression of nanosecond high-voltage pulses based on two-stage hybrid scheme. , 2017, The Review of scientific instruments.

[18]  Shiyao Lin,et al.  Runaway electrons generated during spontaneous disruptions in the EAST tokamak , 2017 .

[19]  M. Yalandin,et al.  Formation of 1.4 MeV runaway electron flows in air using a solid-state generator with 10 MV/ns voltage rise rate , 2018 .

[20]  Cheng Zhang,et al.  Detection of x-ray emission in a nanosecond discharge in air at atmospheric pressure. , 2010, The Review of scientific instruments.

[21]  Ute Ebert,et al.  Experimental study on hard x-rays emitted from metre-scale negative discharges in air , 2012, 1501.00782.

[22]  V. Tarasenko,et al.  Generation of runaway electrons and X-ray emission during breakdown of atmospheric-pressure air by voltage pulses with an ∼0.5-μs front duration , 2015 .

[23]  V. Tarasenko,et al.  Methods for recording the time profile of single ultrashort pulses of electron beams and discharge currents in real-time mode , 2016 .

[24]  L. Babich,et al.  Subnanosecond pulses of runaway electrons generated in atmosphere by high-voltage pulses of microsecond duration , 2009 .

[25]  V. Tarasenko,et al.  Note: measurement of extreme-short current pulse duration of runaway electron beam in atmospheric pressure air. , 2012, The Review of scientific instruments.