Experimental tests of a mass-angle spectrograph with poloidal ion optics

Abstract

A new mass spectrograph for making simultaneous measurements of the mass-angle distributions of charged particles in the energy range up to 30 keV has been tested. The analyzer serially combines two rotationally symmetric poloidal analyzers to achieve a nearly double-focusing image in the radial plane and a 360° field-of-view in the azimuthal direction. Experimental tests have provided information on first- and second-order imaging properties, and have furthermore led to the development of highly effective antiscattering baffles for reducing particle background. The experimental results obtained with this laboratory prototype agree well with the predictions of the semiempirical theory for poloidal analyzers.