Spacecraft potential effects on electron moments derived from a perfect plasma detector

Vincent Génot (1) , S. J. Schwartz (1)

1 AU - Astronomy Unit [London]

A complete computation of the effect of the spacecraft potential on electron moments is presented. We adopt the perfect detector concept to estimate how measured density, velocity and temperature are affected by the constraints imposed by the detector, such as the finite lower energy cutoff and the spacecraft potential. We investigate the role of the potential in different plasma regimes usually crossed by satellites. It appears that the solar wind is the region where the moments are most compromised, as the particle temperature is low. To a lesser extent the moments calculated in the magnetosheath may also deviate from the real moments, displaying up to 40% overestimation for the density under typical detector operation. The analysis allows us to identify a range of spacecraft potential values which minimizes the variation in the estimation; it is found that it corresponds to the common value adopted by potential controlling experiments.

Domaines: Océan, Atmosphère; Sciences de la Terre; Planétologie et astrophysique de la terre [astro-ph.EP]; Planétologie et astrophysique de la terre [astro-ph.EP]; Instrumentation et méthodes pour l'astrophysique [astro-ph.IM]; Instrumentation et méthodes pour l'astrophysique [astro-ph.IM]

Vincent Génot, S. J. Schwartz. Spacecraft potential effects on electron moments derived from a perfect plasma detector. Annales Geophysicae, 2004, 22 (6), pp.2073-2080. ⟨hal-00317433⟩