Further Evidence for Carbon Isotopic Structure in the λλ5797 and 6614 Diffuse Interstellar Bands
Bibliographic record
Abstract
Profiles of the λλ5797 and 6614 diffuse interstellar bands (DIBs) in our high-resolution spectra ( R = 120,000-60,000) of five stars provide strong support for the model proposed by Webster, in which 13 C atoms are randomly substituted for 12 C in highly symmetric molecules. These stars have narrow interstellar Na D lines, and the DIB profiles can be reproduced, as predicted, by a band of equally spaced, equally wide Gaussians with a Poisson intensity distribution. Other good fits are possible with components of unequal FWHM, but the widths, positions, and relative amplitudes of the components then differ from star to star, which is less credible for a common absorber. The average numbers of 13 C atoms per molecule derived from the model are about 0.95 and 1.41 for the λλ5797 and 6614 DIBs, respectively, which correspond to between 40 and 100 carbon atoms per molecule. Sharp features in the cores of the λ5797 DIB are not exactly matched by the Gaussians, which implies a more complex intrinsic structure. For HD 37061 in Orion, both DIBs are weak and have a component on the short-wavelength side of the normal profile, possibly indicating higher rotational temperatures.
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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 | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".