The curious case of II Lup: a complex morphology revealed with SAM/NACO and ALMA
Bibliographic record
Abstract
We present the first-ever images of the circumstellar environment of the carbon-rich asymptotic giant branch (AGB) star II Lup in the infrared and sub-mm wavelengths, and the discovery of the envelope’s non-spherical morphology with the use of high angular resolution imaging techniques with the sparse aperture masking mode on NACO/Very Large Telescope (which enables diffraction-limited resolution from a single telescope) and with the Atacama Large Millimeter/submillimeter Array (ALMA). We have successfully recovered images in Ks (2.18 |$\mu$|m),L' (3.80 |$\mu$|m), and M' (4.78 |$\mu$|m) that revealed the non-spherical morphology of the circumstellar envelope around II Lup. The stellar surface of the AGB star is unresolved (i.e. ≤30 mas in Ks), however, the detected structure extends up to 110 mas from the star in all filters. Clumps have been found in the Ks maps, while at lower emission levels a hook-like structure appears to extend counterclockwise from the south. At larger spatial scales, the circumstellar envelope extends up to approximately 23 arcsec, while its shape suggests a spiral at four different molecules, namely CO, SiO, CS, and HC3N, with an average arm spacing of 1.7 arcsec that would imply an orbital period of 128 yr for a distance of 590 pc.
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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".