New type of compact electrostatic energy analyzer adequate to measurement of charge exchange neutral particles with a low counting yield

A new type of compact electrostatic cylindrical energy analyzer originally providing a deflection angle of π/22 has been designed with the aim of measuring energy spectra of charge exchange neutral particles in the tandem mirror GAMMA10. The essential advantage of the use of this analyzer is that a large entrance aperture can be adopted with high energy resolution so that high incident current is analyzed, while the radius of the cylindrical electrodes remain compact. Characteristics of the analyzer are discussed using computer simulations of ion trajectories including an effect of fringing field obtained by finite-element method as well as small-angle scattering in stripping collisions of hydrogen atoms.