EGU2020-3698
https://doi.org/10.5194/egusphere-egu2020-3698
EGU General Assembly 2020
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Dust impact signals detected by Cassini RPWS instrument at Saturn

Libor Nouzak1, Jiří Pavlů1, Jakub Vaverka1, Jana Šafránková1, Zdeněk Němeček1, David Píša2, Mitchell Shen3,4, Zoltan Sternovsky3,4, and Shengyi Ye5
Libor Nouzak et al.
  • 1Charles University, Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Prague, Czechia (nouzak@aurora.troja.mff.cuni.cz)
  • 2Institute of Atmospheric Physics, Czech Academy of Sciences, Prague, Czech Republic
  • 3Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
  • 4Aerospace Eng. Sci. Department, Univ. of Colorado, Boulder, CO 80309, USA
  • 5Department of Earth and Space Sciences, Southern University of Science and Technology (SUSTech), Shenzhen, China

Cassini spacecraft spent at Saturn almost half of the Saturn year. During these 13 years in the Saturn magnetosphere, the RPWS (Radio Plasma Wave Science) instrument recorded more than half a million of waveforms with signatures that can be interpreted as dust impact signals. The RPWS antennas in both dipole and monopole configurations operated with 10 kHz or 80 kHz sampling rates during the mission.
We qualitatively and quantitatively analyze the registered waveforms taking into account the spacecraft potential, density of the ambient plasma, magnitude of the Saturn’s magnetic field and its orientation with respect to the spacecraft. The magnetic field orientation is also used for distinguishing between signals resulting from dust impacts and signals produced by solitary waves, which can exhibit similar shapes. The results of analysis are compared with a prediction of the dust impact model that was recently developed on a base of laboratory simulations. The simulations used the reduced model of Cassini that was bombarded with submicron-sized iron grains in the velocity range of 1–40 km/s at the 3 MV dust accelerator operated at the LASP facility of University of Colorado. The model predicts generation of impact signals due to different fractions of collected and escaped electron and ion charges from the impact plasma plume and different timescales of their expansion. The core of the paper is devoted to a discussion of differences between model predictions and observations.

How to cite: Nouzak, L., Pavlů, J., Vaverka, J., Šafránková, J., Němeček, Z., Píša, D., Shen, M., Sternovsky, Z., and Ye, S.: Dust impact signals detected by Cassini RPWS instrument at Saturn, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3698, https://doi.org/10.5194/egusphere-egu2020-3698, 2020.