Injection of metallic elements into an electron-beam ion trap using a Knudsen cell

Abstract

A method of injecting metallic elements into an electron-beam ion trap (EBIT) is described. The method is advantageous over the conventional coaxial and pulsed injection methods in two ways: (a) complicated switching of injection and extraction beams can be avoided when extracting beams of highly charged ions from the EBIT and (b) a beam of stable intensity can be achieved. This method may be applicable to any metallic elements or metallic compounds that have vapor pressures of ∼0.1Pa at a temperature lower than 1900°C. We have employed this method for the extraction of highly charged ions of Bi, Er, Fe, and Ho.