EGU23-9371, updated on 16 May 2023
https://doi.org/10.5194/egusphere-egu23-9371
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Asymmetry in the Terrestrial Plasma Sheet Driven by Dayside Dynamics

Maher A. Dayeh1,2, Michael J. Starkey1, Steven M. Petrinec3, Stephen A. Fuselier1,2, Justyna M. Sokół1, Keiichi Ogasawara1,2, Jamey R. Szalay4, David J. McComas4, Eric J. Zirnstein5, and Nathan A. Schwadron5,4
Maher A. Dayeh et al.
  • 1Southwest Research Institute, San Antonio TX, USA (maldayeh@swri.edu)
  • 2University of Texas at San Antonio, San Antonio TX, USA
  • 3Lockheed Martin Advanced Technology Center, Palo Alto CA, USA
  • 4Princeton University, Princeton NJ, USA
  • 5University of New Hampshire, Durham NH, USA

The Interstellar Boundary Explorer (IBEX) mission continues to provide energetic neutral atom (ENA) observations of the heliosphere and Earth’s magnetosphere from a global perspective and including spatial, temporal, and energy information. Due to its orbit, IBEX routinely observes the magnetosphere from a side-viewing vantage point, with a field-of-view that is nearly perpendicular to the day-night plane. This enables the construction of composite ENA images at different energies (0.5 – 6.0 keV) for convected solar wind conditions, which provides global insights into different magnetospheric plasma regions and processes.

Earth’s plasma sheet plays a crucial role in the global circulation of plasma throughout the magnetosphere. The structure of the plasma sheet is driven by a combination of effects including interplanetary magnetic field (IMF) and solar wind conditions, internal magnetospheric processes, and Earth’s dipole tilt angle.

This work examines the structure of the plasma sheet in the X-Z geocentric ecliptic plane (GSE) using ENA images from IBEX. The thickness and extent of the plasma sheet is compared for conditions of prolonged northward and southward IMF. We report on a North-South asymmetry in the plasma sheet that is related to the IMF orientation and is driven by a combination of dayside magnetic reconnection effects and high dipole tilt. Results provide evidence of dayside reconnection driving plasma sheet dynamics.

How to cite: Dayeh, M. A., Starkey, M. J., Petrinec, S. M., Fuselier, S. A., Sokół, J. M., Ogasawara, K., Szalay, J. R., McComas, D. J., Zirnstein, E. J., and Schwadron, N. A.: Asymmetry in the Terrestrial Plasma Sheet Driven by Dayside Dynamics, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-9371, https://doi.org/10.5194/egusphere-egu23-9371, 2023.