The JCMT Spectral Legacy Survey: physical structure of the molecular envelope of the high-mass protostar AFGL2591
Bibliographic record
Abstract
Context. The understanding of the formation process of massive stars (>∼8 M) is limited, due to a combination of theoretical com-plications and observational challenges. The high UV luminosities of massive stars give rise to chemical complexity in their natal molecular clouds, and affect the dynamical properties of their circumstellar envelopes. Aims. We investigate the physical structure of the large-scale (∼104–105 AU) molecular envelope of the high-mass protostar AFGL2591. Methods. Observational constraints are provided by spectral imaging in the 330–373 GHz regime from the JCMT Spectral Legacy Survey and its high frequency extension. While the majority of the ∼160 spectral features from the survey cube are spatially unre-solved, this paper uses the 35 that are significantly extended in the spatial directions. For these features we present integrated intensity maps and velocity maps. The observed spatial distributions of a selection of six species are compared with radiative transfer models based on (i) a static spherically symmetric structure, (ii) a dynamic spherical structure, and (iii) a static flattened structure. Results. The maps of CO and its isotopic variations exhibit elongated geometries on scales of ∼100′′, and smaller scale substructure is found in maps of N2H+, o-H2CO, CS, SO2, C2H, and various CH3OH lines. In addition, a line of sight velocity gradient is apparent in maps of all molecular lines presented here, except SO, SO2, and H2CO. We find two emission peaks in warm (Eup ∼ 200 K)
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| 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".