Possible early release of protons during breakout reconnection

Determine whether protons were released early, potentially simultaneously with the electrons, during the breakout-reconnection-associated particle injection episode.

Background

Velocity-dispersion and time-shift analyses yield different inferred release times for electrons and protons. The electron release is estimated near 13:37 UT, whereas the proton analysis gives a later release interval of approximately 13:54–14:03 UT.

The authors emphasize that uncertainties in interplanetary transport, including scattering and pitch-angle distributions, prevent them from excluding an earlier proton release. Thus, whether protons were injected simultaneously with the electrons remains unresolved.

References

This proton release time appears to be inconsistent with the inferred electron release time. However, an early release of protons, potentially simultaneous with the electron release, cannot be excluded. Due to uncertainties in interplanetary transport, including particle scattering and the pitch-angle distribution, the present analysis is unable to definitively rule out this possibility.

— Breakout/Interchange Reconnection as a driver of Jets, Fast CME, and Solar Energetic Particles  (2608.23362 - Kumar et al., 24 Aug 2026) in Section 3.3, subsection “Multi-spacecraft observations of SEPs”