Bibliographic record
Abstract
Observations of Betelgeuse show that (1) the photospheric spectral lines are very broad with a 1/e width of 11 km s-1, but they have stable shapes with time as the star varies in other ways; (2) all the spectral lines within the observed wavelength region change their depths by essentially the same factor and in phase with the photometric brightness of the star on timescales of months; (3) small deviations from perfect scaling of the line depths imply temperature variations that to first order are in phase with the line depths, i.e., cooler temperatures go with weaker lines; and (4) to second order, the temperature variations lag behind the changes in line depths by ~5 days. The hypothesis of changing continuous opacity is put forward as a coherent explanation of all of these spectroscopic and photometric effects. In addition, the bright spot observed by others is explained as a region where the opacity does not change; it is not a giant convection cell. The physical reason for the opacity change has yet to be identified. Structure in the cores of spectral lines varies on the timescale of a day, and this may be the signature of giant convection cells, but other interpretations are also possible, including hot spots, prominences, or nonradial oscillations.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".