Experimental study on electron beam energy recovery system using a laser-heated electron gun and a multistage electron collector for highly efficientbeam application

An experiment on electron beam energy recovery systems has been performed u sing a laser-heated electron gun and a multistage electron collector. Model ing of the laser heating indicates that the cathode temperature is proporti onal to the one-fourth power of laser power. The energy recovery efficiency of 99.8% of the designed collector is calculated using a computer code wit h a beam current of about 10 mA and -75 keV. In the first phase of the reco very experiment, potentials of the collector electrodes are provided throug h a voltage divider of several hundred megaohms. In order to overcome the d rawback of voltage-divider resistance, two high-voltage power supplies are provided in the second phase of the experiment, and charge and energy recov ery efficiencies are measured.