<i>AKARI</i>NEAR-INFRARED SPECTRAL OBSERVATIONS OF SHOCKED H<sub>2</sub>GAS OF THE SUPERNOVA REMNANT IC 443
Bibliographic record
Abstract
We present near-infrared (2.5–5.0 μm) spectra of shocked H 2 gas in the supernova remnant IC 443, obtained with the satellite AKARI . Three shocked clumps—known as B, C, and G—and one background region were observed, and only H 2 emission lines were detected. Except in clump B, the extinction-corrected level population shows the ortho-to-para ratio of ∼3.0. From the level populations of clumps C and G—both the one obtained with AKARI and the one extended with previous mid-infrared observations—we found that the υ = 0 levels are more populated than the υ>0 levels at a fixed level energy, which cannot be reproduced by any combination of H 2 gas in local thermodynamic equilibrium. The populations are described by the two-density power-law thermal admixture model, revised to include the collisions with H atoms. We attributed the lower ( n (H 2 )=10 2.8 –10 3.8 cm −3 ) and higher ( n (H 2 )=10 5.4 –10 5.8 cm −3 ) density gases to the shocked H 2 gas behind C-type and J-type shocks, respectively, based on several arguments including the obtained high H i abundance n (H i )/ n (H 2 ) = 0.01. Under the hierarchical picture of molecular clouds, the C-type and J-type shocks likely propagate into "clumps" and "clouds" (interclump media), respectively. The power-law index b of 1.6 and 3.5, mainly determined by the lower density gas, is attributed to the shock-velocity diversity, which may be a natural result during shock–cloud interactions. According to our results, H 2 υ = 1 → 0 S (1) emission is mainly from J shocks propagating into interclump media. The H 2 emission was also detected at the background region, and this diffuse H 2 emission may originate from the collisional process in addition to ultraviolet photon pumping.
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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".