The Solar Probe ANalyzer -Ions on Parker Solar Probe
R. Livi, D. E. Larson, J. C. Kasper, R. Abiad, A. W. Case, K. G. Klein, D. W. Curtis, Gregory Dalton, M. L. Stevens, K. E. Korreck, G. C. Ho, Miles Robinson, Chris Tiu, P. L. Whittlesey, J. L. Verniero, J. S. Halekas, J. McFadden, Mario Marckwordt, Amanda Slagle, Mamuda Abatcha, A. Rahmati
Abstract
The Solar Probe ANalyzer for Ions (SPAN-I) onboard NASA’s Parker Solar Probe (PSP) spacecraft is an electrostatic analyzer with time-of-flight capabilities that measures the ion composition and three dimensional distribution function of the thermal corona and solar wind plasma. SPAN-I measures the energy per charge of ions in the solar wind from 2 eV to 30 keV with a field-of-view of 247.5 • x 120 • while simultaneously separating H + from He ++ to develop 3D distribution functions of individual ion species. These observations, combined with reduced distribution functions measured by the Sun-pointed Solar Probe Cup (SPC), will help us further our understanding of the solar wind acceleration and formation, the heating of the corona, and the acceleration of particles in the inner heliosphere. This paper describes the instrument hardware, including several innovative improvements over previous time-of-flight (TOF) sensors, the data products generated by the experiment, and the ground calibrations of the sensor.