New Spectrometer ULTIMAN for Space Plasma Research

Measurements of ion velocity distributions are one of basic goals of space plasma studies. There is variety of ion and electron spectrometers (see, for example, Wüest et al., 2007; Young et al., 2007; Zurbuchen and Gershman, 2016; Vaisberg et al., 2016). The most commonly used ion spectrometer is the top-hat analyzer (Carlson et al., 1983) consisting of a toroidal electrostatic analyzer, an electrostatic scanner, and a timeof-flight section with thin foil as a start element and ion preacceleration. We describe a new energy-mass analyzer with an electrostatic scanner providing a hemispheric field of view with small aberration, a toroidal electrostatic analyzer, and a time-of-flight synchronizer with a simple gate. It provides desirable hemisphere scanning, wide energy range, and reasonable mass resolution to meet most space exploration challenges. It can provide detailed measurements of the ion velocity distribution of ion species without significant gaps to obtain the structure of the hot plasma flow. With simple electrooptics elements this analyzer can be easily modified for many plasma research purposes.