Identifying the magnetotail source region leading to preonset poleward boundary intensifications
Bibliographic record
Abstract
Abstract Substorm auroral onset is often preceded by plasma sheet flow bursts, poleward boundary intensifications (PBIs), and subsequent auroral streamers, suggesting that enhanced transient flows in the plasma sheet propagating toward the near‐Earth plasma sheet play an important role in leading to substorm onset. This study aims at determining the magnetotail source region of preonset PBIs and plasma sheet flows by using the ARTEMIS spacecraft coordinated with the THEMIS all‐sky imager array. ARTEMIS has an advantage of measuring flows between the nominal near‐Earth neutral line (NENL) and distant neutral line (DNL) locations, and thus, the flow direction allows identifying which source region is dominant. We found three preonset conjunction events, and all cases show earthward flow bursts ~10–30 min before substorm onset when PBIs and streamers are detected in the conjugate ionosphere. This time lag is sufficiently long to bring plasma from the ARTEMIS location toward the near‐Earth plasma sheet before onset. The earthward flow direction indicates that preonset enhanced flow channels leading to precursor PBIs originate from further downtail of ARTEMIS, possibly from DNL rather than from NENL. The flow direction changes to tailward after the substorm onset, suggesting that NENL is not related to preonset flow and auroral activity but becomes active during the expansion phase.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 | 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".