Magnetospheric sawtooth oscillations are observed during strong and steady solar wind driving conditions. The simulation results of our global magnetohydrodynamics (MHD) model with embedded kinetic physics show that when the total magnetic flux carried by constant solar wind exceeds a threshold, sawtooth‐like magnetospheric oscillations are generated. Different from previous works, this result is obtained without involving time‐varying ionospheric outflow in the model. The oscillation period and amplitude agree well with observations. The simulated oscillations cover a wide range of local times, although the distribution of magnitude as a function of longitude is different from observations. Our comparative simulations using ideal or Hall MHD models do not produce global time‐varying features, which suggests that kinetic reconnection physics in the magnetotail is a major contributing factor to sawtooth oscillations.
- NSF-PAR ID:
- 10032464
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 121
- Issue:
- 10
- ISSN:
- 2169-9380
- Page Range / eLocation ID:
- 9688 to 9700
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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