The Mercury Plasma Particle Experiment (MPPE) suite is a comprehensive instrument package to observe the solar wind at
Mercury’s position and the whole plasma environment at Mercury. It consists of seven sensors including Mercury Electron Analyzers
(MEA1 and MEA2), Mercury Ion Analyzer (MIA), Mass Spectrum Analyzer (MSA), High-Energy Particle instrument for electron (HEP-e),
High-Energy Particle instrument for ion (HEP-i), and Energetic Neutrals Analyzer (ENA).
These sensors measure plasma, high-energy particles and energetic neutral atoms with sufficiently high time resolution,
wide energy and dynamic range, wide angle coverage, and high mass resolution.

  The Mass Spectrum Analyzer (MSA) that is part of the MPPE consortium onboard Mio, measures mass resolved 3D distribution functions 
  of ions from 1 eV/q up to 38 keV/q. As such, it allows us to investigate the magnetospheric plasma dynamics and to characterize the c
  ontribution of ions of planetary origin such as Na+ or K+. MSA consists of a spherical top-hat for energy per charge analysis, 
  followed by a polarized Time-Of-Flight chamber for mass per charge discrimination. The "reflectron" design adopted in this TOF chamber 
  leads to isochronous times of flight ; hence, an enhanced mass resolution (above 50) of the measured ions.