Commissioning of a powerful electron gun for electron-ion crossed-beams experiments

The sensitivity of an electron-ion crossed-beams experiment is mainly determined by the densities of both beams in the interaction region. Aiming at the extension of the available range of accessible electron energies and densities, a new high-power electron gun has been developed and fabricated. It delivers a ribbon-shaped beam with currents of up to 1 A at variable energies reaching 3500 eV at the maximum. The design goals of the gun are being met by using a configuration of electrodes, which allows for a variety of operation modes. Here, we report on the results of the ongoing tests of the new electron gun. In particular, electron-impact ionization cross sections of He⁺ and Xe⁵⁺ ions were measured employing the animated crossed-beams technique. The results are in excellent agreement with literature data.