Asymmetric reconnection at the bow shock
- 1Umeå University, Department of Physics, Umeå, Sweden
- 2South West Research Institute, San Antonio, TX, USA
- 3Royal Institute of Technology (KTH), Stockholm, Sweden
Can reconnection be triggered as a directional discontinuity (DD) crosses the bow shock? Here we present some unique observations of asymmetric reconnection at a quasi-perpendicular bow shock as an interplanetary DD is crossing it simultaneously with the Magnetospheric Multiscale (MMS) mission. The data show indications of ongoing reconnection at the bow shock southward of the spacecraft. The DD is also observed by several upstream spacecraft (ACE, WIND, Geotail, and THEMIS B) and one downstream in the magnetosheath (Cluster 4), but none of them resolve signatures of ongoing reconnection. We therefore suggest that reconnection was temporarily triggered as the DD was compressed by the shock. Bow shock reconnection is inevitably asymmetric with both the density and the magnetic field strength being higher on one side of the X-line (the magneosheath side) than on the other side where the plasma flow also is supersonic (the solar wind side). Asymmetric reconnection of the bow shock type has never been studied before, and the data discussed here are hence unique.
How to cite: Gunell, H., Hamrin, M., Goncharov, O., De Spiegeleer, A., Fuselier, S., Mukherjee, J., and Vaivads, A.: Asymmetric reconnection at the bow shock, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4750, https://doi.org/10.5194/egusphere-egu2020-4750, 2020.
