First results of ground-based optical measurements of the ion-neutral coupling within the polar region.
Bibliographic record
Abstract
Ground-based imaging Fabry-Perot interferometer (FPI) optical measurements of the ion-neutral coupling between the F-region plasma and the polar thermosphere were made during the 2022-2023 northern winter season at the Kjell Henriksen Observatory (78.2 N, 15.6 E). By observing in sequence with a filter wheel located in front of the etalon, measurements of the spectral profiles of both the O+ 732 nm emission and the O 630 nm emission for each direction selected by a double axis mirror system were used to determine Doppler shifts and Doppler broadenings. The 732 O+ results were analyzed to determine the averaged line-of-sight F-region drift speed and ion temperature for a typical exposure time of 120 s. For the 630 nm O emission, the averaged line-of-sight wind speed and neutral temperature were determined for an exposure time of 30 s. The FPI clear aperture was 120 mm, the FPI etalon gap separation was 1.4925 cm, each filter bandwidth was ~0.8 nm, and the focal length for an apochromatic lens assembly was 300 mm enabling the imaging observations of 12 rings for the 630 nm O emission and 11 rings for the 732 nm O+ emission. The primary production excitation source of the observed 732 nm O+ emission was that of solar EUV photoionization but the soft particle energetic precipitation associated with the polar cusp region also contributed significantly to the production of both emissions, especially during the noon sector period. Contamination by the 1PG molecular band emission of N2 was generally non-existent. It was found there was sufficient O+ emission for almost all directions chosen to determine the line-of-sight ion drift and ion temperatures with reasonable accuracy. Contamination of the O+ 732 emission by the 731.6 nm OH doublet associated with the OH hyperfine structure caused by lambda splitting was always present in each O+ observed spectral profile. Removal of this emission in the analysis proved to be straightforward as one of the two OH peaks is seen clear of the O+ spectral profile, and its intensity could be used after the step of annular summing to normalize the OH structure for removal from the composite ring-integrated interferometric spectral profile. The two peaks of the O+ 732 nm doublet were almost coincident within each interferogram order. Results will be analyzed: 1), to search for indications of anti-sunward drift of the F-region plasma, 2) to determine the degree of variability of the observed plasma drifts, and 3) to determine the extent of Joule heating creating differences between the ion and neutral temperatures. The data obtained in the magnetic zenith direction will be examined to search for evidence of possible ion outflow.
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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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 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) | 0.003 | 0.001 |
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".