Photometric Study of Transition Objects Which Lie Between the Asymptotic Giant Branch (AGB) and Planetary Nebulae (PNe)
Bibliographic record
Abstract
Post-Asymptotic Giant Branch (post-AGB) stars are generally believed to be on their way to the planetary nebula stage. However, there has been a question about the evolutionary path for the low-mass ones. We investigate the evolution of 31 very likely and possible post-AGB candidates selected from the Torun catalogue of Galactic post-AGB sources. The sources in the sample belong to the IRAS selected sources (IRASsel), High Galactic latitude supergiants (hglsg), High Galactic latitude B-type supergiants (hglB) and Bright stars with infrared (IR) excess (IRexc) classifications in the catalogue and are found to lie between AGB and planetary nebulae (PNe). Out of the 31 selected sources, 26 were studied. We compared the IRAS color-color plots of these sources with that of van der Veen & Habing and Szczerba and found that the 26 sources are possibly post-AGB stars. Their temperature and dynamical time plots showed that 11 objects in our sample have their shells completely detached. One object was found to be on the evolutionary track of Mcore = 0.55Mo and may likely evolve to a white dwarf, by-passing the PN stage.
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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 | 0.002 | 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".