Ion source for MKh-7304 mass spectrometer

The weak dependence of the resolution of monopole mass spectrometers on the relative ion energy spread provides extensive opportunities for improvement of the ion source. In the stock ion source of the MKh-7304 mass spectrometer, the ionization region is greatly narrowed by the slits that collimate the electron beam. In the proposed ion source, the ionization region is made transparent to electrons. After it intersects this region, an electron enters a retarding electric field and is returned to the ionization region. In accomplishing oscillatory motion, the electrons repeatedly intersect the ionization region, which substantially increases the efficiency of ion production. These same principles underlie ionization converters with axial collectors.