Time evolution of the subauroral electric fields: A case study during a sequence of two substorms
Bibliographic record
Abstract
The temporal evolution of the subauroral polarization stream (SAPS) is investigated using the Doppler velocity observations by the Unwin HF radar in conjunction with the simultaneously observed auroral luminosity and plasma convection reversal regions. The event under study of 14 December 2004, 1000–1600 UT, occurred during geomagnetically quiet conditions when a sequence of two substorms separated by ∼2 hours was observed by the IMAGE satellite. It is shown that the SAPS appeared shortly after the first substorm onset and continued to dominate the westward plasma convection at subauroral magnetic latitudes 59°–63°S for ∼6 hours. An unexpected exception occurred near the second substorm onset time when a narrow channel of weaker SAPS westward convection became embedded in the slow eastward drifting plasma for a short ∼25‐min period, which was attributed to the equatorward expansion of the dawn convection cell during the growth and expansion phases of the second substorm. Another remarkable plasma convection feature was observed in the same 25‐min period ∼5° poleward of SAPS; this was a narrow “mirror” channel of the eastward drifting plasma parallel to the main SAPS channel. It is argued that the latter feature may also be caused by the equatorward expanding dawn convection cell whose streamlines become compressed by and aligned with the SAPS poleward edge. A possible relationship between the SAPS intensity and its position relative to the auroral oval is also investigated. The results suggest that the magnetosphere‐ionosphere feedback processes within SAPS become more effective as the equatorward edge of the eastward convection region retreats poleward with the SAPS position much less affected by the auroral dynamics.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".