Cusp type electrostatic analyzer for measurements of medium energy charged particles

We have developed a new electrostatic analyzer which enables medium energy (≲200 keV∕q) plasma particle measurements with full solid angle coverage. The design of the test model realizes the uppermost measurement energy of ∼200 keV∕q with applied high voltages of ±5 kV. Laboratory experiments with the test model analyzer show that its performance agrees with numerical simulations. The test model design is well suited for combination with a mass analysis unit, while our new design can also be applied to medium energy electron measurements. Medium energy ion/electron sensors with this new design will surely be appreciated for upcoming space missions that will observe hot/energetic plasma structures in the regions such as the inner magnetosphere or reconnection region.