Abstract

The generation of intense electron beams by superposing two discharges has been reported, recently /1/, /2/. A new device which delivers a 0.2 - 0.5 m length high intensity electron beam in low pressure (0.1 - 3 mbar) argon discharge tubes is presented. A common K₁K₂ hollow cathode serves both as a pulsed discharge cathode and a d.c. discharge cathode. A₁ and A₂ are the main discharge and the d.c. discharge anodes, respectively. A stable electron beam is developing longitudinally, centered inside the tube, only for critical values of the auxiliary discharge current, for a given gas pressure. A 2 mm diameter plasma channel which is produced by the electron beam itself is surrounding the electron beam. A pulsed high voltage supply (60 kV ,100 ns, 500 A) and a continuous 6kV/200 mA power supply are used. The temporal behaviour of the electron beam was determined by means of a Faraday cup and a 500 Mhz Tektronix 540 oscilloscope. Less than 4 ns FWHM beam intensity was found. The power density of the electron beam is estimated to be about 3. 10¹⁰ W / cm².

© 1996 IEEE