The effect of air pressure(12.5,25,50,and 100 kPa)on the gen eration of runaway electron beams in a non-uniform electric field when applying voltage pulses(~35 kV)with a rise time of?200 ns has been studied.The result...The effect of air pressure(12.5,25,50,and 100 kPa)on the gen eration of runaway electron beams in a non-uniform electric field when applying voltage pulses(~35 kV)with a rise time of?200 ns has been studied.The results show that the discharge has various stages:streamer,diffuse,and spark.Initially,a wide streamer develops in the gap and a diffuse discharge is formed.A spark is formed u 100 ns after the breakdown.The current pulse of a supershort avalanche electron beam(SAEB)was measured with a collector at various pressures of air.Experiments show that there are two modes of generation of run away electrons.At an air pressure of 25-100 kPa,a single SAEB current pulse with a full width at half-maximum(FWHM)of 120-140 ps is observed.At the air pressure of 12.5 kPa,two current pulses of the electron beam are observed.FWHM of the first and second current pulses are ul40ps and u300 ps,respectively.The current pulse amplitude of the second electron beam is higher than that of the first one,but the electron energy is less.展开更多
文摘The effect of air pressure(12.5,25,50,and 100 kPa)on the gen eration of runaway electron beams in a non-uniform electric field when applying voltage pulses(~35 kV)with a rise time of?200 ns has been studied.The results show that the discharge has various stages:streamer,diffuse,and spark.Initially,a wide streamer develops in the gap and a diffuse discharge is formed.A spark is formed u 100 ns after the breakdown.The current pulse of a supershort avalanche electron beam(SAEB)was measured with a collector at various pressures of air.Experiments show that there are two modes of generation of run away electrons.At an air pressure of 25-100 kPa,a single SAEB current pulse with a full width at half-maximum(FWHM)of 120-140 ps is observed.At the air pressure of 12.5 kPa,two current pulses of the electron beam are observed.FWHM of the first and second current pulses are ul40ps and u300 ps,respectively.The current pulse amplitude of the second electron beam is higher than that of the first one,but the electron energy is less.
