Survey of whistler-mode emissions behind the terrestrial bow shock

0518226 - ÚFA 2020 US eng A - Abstrakt
Píša, David - Santolík, Ondřej - Souček, Jan - Krupař, Vratislav - Krupařová, Oksana
Survey of whistler-mode emissions behind the terrestrial bow shock.
AGU Fall Meeting. Washington: American Geophysical Union, 2019. SM51C-3195.
[AGU Fall Meeting 2019. 09.12.2019-13.12.2019, San Francisco]
Institucionální podpora: RVO:68378289
Klíčová slova: magnetosphere * planetary bow shock region * whistler mode waves
Obor OECD: Fluids and plasma physics (including surface physics)
https://agu.confex.com/agu/fm19/meetingapp.cgi/Paper/536385

The planetary bow shock is the boundary region where the solar wind plasma flow encountering the magnetosphere gets heated and slowed down to a subsonic speed. Physical processes in the region behind the bow shock can lead to a local electron temperature anisotropy. This plasma temperature anisotropy can result in the growth of the whistler-mode waves, which dissipates the free energy in the plasma downstream of the collisionless shock. We present a survey of more than 500 bow shock crossings by a constellation of four Cluster spacecraft, analyzing measurements of the STAFF-SA electromagnetic wave instrument and PEACE electron analyzer. We have identified bow shock crossings of all four spacecraft as well as the time-frequency intervals with intense whistler-mode wave signatures in the vicinity of the shock. For each time interval, we estimated the whistler-mode wave growth rate from the PEACE electron distribution function and compared it to the observed wave polarization and propagation properties calculated from STAFF-SA spectral matrices. In this work, we investigated the spatial, frequency, and power distribution of the observed waves and analyzed the wave properties as a function of upstream solar wind and bow shock properties.
Trvalý link: http://hdl.handle.net/11104/0303385