Energy and Oscillatory Characteristics of a High-Power Long-Pulse Electron Beam

Alexander Arkhipov^a, Vladimir Engelko^b,Vladimir Kovalev^b, Maxim Mishin^a, Georg Mueller^c and Gennadi Sominski^a

^aSt. Petersburg State Politechnic univ., 29 Politechnicheskaya, St. Petersburg, 195251, Russia

^bEfremov Institute of Electrophysical Apparatus, Metallostroi, St. Petersburg, 189631, Russia

^cIHM, Forschungszentrum Karlsruhe, Postfach 3640, Karlsruhe, D-76021, Germany

Abstract. For the electron beam of GESA II material processing facility, electron energy distributions have been measured. General parameters of these spectra (such as mean pitch angle) were found to be in good agreement with the results of simulations and measurements with other techniques. Yet, for some of regimes, substantial broadening of the full energy distribution was observed, and a noticeable fractions of abnormally accelerated electrons appeared, which may be interpreted as a sign of non-conservative processes developing in the beam. In further special investigations, a few different modes of oscillations were discovered, one of them presumably associated with oscillations of a space charge bunch between the gun and the target.