On the kinematics and thickness of the terrestrial bow shock

0474649 - ÚFA 2018 DE eng A - Abstract
Krupařová, Oksana - Krupař, Vratislav - Santolík, Ondřej - Souček, Jan - Šafránková, J. - Němeček, Z. - Němec, F. - Maksimovic, M.
On the kinematics and thickness of the terrestrial bow shock.
Geophysical Research Abstracts. Göttingen: European Geosciences Union, 2017. EGU2017-9078. ISSN 1607-7962.
[EGU General Assembly 2017. 23.04.2017-28.04.2017, Vienna]
Institutional support: RVO:68378289
Keywords : magnetosphere * solar wind * terrestrial bow shock * wave-particle interactions
Subject RIV: BL - Plasma and Gas Discharge Physics
http://meetingorganizer.copernicus.org/EGU2017/EGU2017-9078.pdf

The bow shock (BS) is formed due to the continuous interaction between the supersonic solar wind and the Earth’s
magnetosphere ahead of the magnetopause. Thanks to its proximity, BS is a perfect object to study a wide range
of phenomena related to collisionless shocks and wave-particle interactions. We have analyzed more than 500
quasi-perpendicular BS crossings between 2001 and 2015 using data retrieved by the magnetometers aboard the
four Cluster spacecraft. Applying a simple timing method to four-point measurement, we estimated the BS normal
direction and velocity along this direction case by case. Next, we applied the Butterworth filter to numerical
derivations of time-intensity profiles to estimate temporal sizes of BS magnetic ramps, and consequently spatial
ones using obtained velocities. We have found that BS ramp scales are statistically around 50 km. We discuss
relation between the BS ramp scales and both Alfven and magnetosonic Mach numbers.
Permanent Link: http://hdl.handle.net/11104/0271653