Abstract

AbstractForeshock bubbles (FBs), transient ion foreshock phenomena formed from highly concentrated suprathermal foreshock ions upstream of solar wind discontinuities, produce intense disturbances in the magnetosphere‐ionosphere system and can accelerate particles to even higher energies. Rotational discontinuities are known to drive FBs. Tangential discontinuities (TDs), however, have not previously been considered as drivers of FBs because they have no normal magnetic field component, preventing access of field‐aligned particles upstream. However, given that suprathermal foreshock ions have gyroradii larger than the width of TDs, they may pass upstream of TDs and generate FBs. Using multipoint observations from Advanced Composition Explorer, WIND, and Time History of Events and Macroscale Interactions during Substorms (THEMIS), we report on two cases of TD‐driven FBs. The FBs were identified using classical FB selection criteria, and the driving TDs were identified using ideal MHD criteria, to within the limits of observational error. Our results add another potential solar wind driver of FBs and imply that FBs may be even more common than previously thought.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.