Experimental investigation of a pseudospark-produced high-brightness electron beam

A high-brightness electron beam produced by a six-gap pseudospark chamber operated in 5--25 kV voltage and 30--70 mTorr pressure ranges is experimentally investigated. The electron beam of current 150 A at an average energy of 20 keV and pulse duration of 10 nsec is extracted with a repetitive frequency of ∼10 Hz. The electron-beam current scales linearly with the breakdown voltage and about 20% of the stored energy is converted into the total beam energy. The time-integrated rms emittance of the electron beam is measured, and a typical value is found to be 65 mm mrad, yielding a normalized brightness of the beam Bn∼2x1010 A/(m2 rad2)