
Many analytical and medical devices are using thorium tungsten wires as ion source. Why use thorium tungsten materials? What about tungsten or neodymium tungsten materials? Electrons are made available from a cathode in the source, which in most cases will use thermionic emission, i.e., heating the material so that electrons gain some energy and are able to escape the work ding of the cathode material (the energy required per electron to leave the material). To lower work ding, manufacturers would…