Transition of Pi2 ULF wave polarization structure from the ionosphere to the ground
Bibliographic record
Abstract
Trains of ultra low frequency (ULF) waves in the Pi2 range (40–150 s) are regularly detected in near‐Earth space. While some Pi2 occur just before substorm onset, others do not show any casual relation to substorm activity so that the Pi2 generation and propagation mechanisms are still unclear. The bulk of information on Pi2 morphology is provided by ground‐based magnetometers, subject to distortions due to transition through the highly conducting lower ionosphere. While space‐borne magnetometers provide important in situ information, they cannot match the spatio‐temporal continuity of ground‐based instruments. In this paper, we devise a novel approach using co‐located high‐frequency ionospheric radars and ground magnetometers for the first direct observation of the Pi2 wave polarization transition between the ionosphere and the ground. Furthermore, application of the Hilbert transform enables us to reconstruct the transition dynamics, which resolves an apparent disagreement between the Pi2 spectra measured by the two instruments.
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 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".