Molecular Line Emission from the Young Planetary Nebula NGC 7027
Bibliographic record
Abstract
NGC 7027 has been observed in eleven molecular species (in seventeen transitions) in the 200 and 300 GHz bands with the James Clarke Maxwell Telescope (Hasegawa & Kwok 2001). The results include a first detection of C2H in this source. The observed spectra of HCO+, H13CO+, HCN, CN, C2H, and CO+ show line widths larger than that of bulk CO emission but coincident with the full width at detection limit of weak wings in CO spectra. The sizes of the HCO+, HCN, and CN emitting regions are 13″ in diameter at half-peak level, significantly smaller than that (60″) of the CO emitting region. The emission of all the observed molecules other than CO and 13CO must originate from a very small volume compared with the entire CO envelope of NGC 7027. Since the central 10″ region is an ionized region, the molecular emission region (except CO) must be geometrically thin (ΔR = 1″ – 2″) and must be close to the ionization front.
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 | 0.001 |
| 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".