Deriving proper electron characteristics in the solar wind from Solar Orbiter observations

Abstract

<p>Solar Orbiter, the latest ESA solar and heliospheric space mission, provides the most recent plasma measurements in the free streaming solar wind across a wide range of the radial distance from the Sun. Electron observations are enabled by the Electron Analyser System (EAS) being part of the Solar Wind Analyser (SWA) suit of instruments. Electron properties are measured in a form of velocity distribution functions (VDFs) with an unprecedent sampling rate of 10 s in the normal operational mode going down to even 8 Hz for limited burst mode snapshots. Regular EAS observations started in mid of 2020 and all data are being continuously made publicly available throughout the ESA's Solar Orbiter Archive (SOAR). Here we present some preliminary user-based methods and techniques of deriving proper electron characteristics from the Level 2 calibrated data set by calculating the required moments of measured VDFs. In particular, we focus on data correction with respect to possible instrument and/or spacecraft related effects. The obtained results are compared and validated by a cross calibration with respect to electron properties derived from the quasi-thermal noise measurements provided by the Radio and Plasma Waves (RPW) instrument, being also part of the in situ plasma payload of the Solar Orbiter mission.</p>