Spectra of Carbon Nanoparticles: Laboratory Simulation of the Aromatic CH Emission Feature at 3.29 μm
Bibliographic record
Abstract
Laboratory spectra of carbon nanoparticles (CNPs) near 3.29 μm show a band whose profile is an excellent match to that of the aromatic CH feature observed in type A emission sources. This band is associated with the CH stretching vibration in polycyclic aromatic hydrocarbon (PAH) molecules having peripheral aliphatic hydrocarbon substituents. Comparison between experimental and observational spectra suggests that the PAH species responsible for the appearance of a CH absorption feature at 3.275 μm is likely the same as that producing emission at 3.29 μm. We also detect a feature at 3.255 μm, attributed to small PAHs with aliphatic side chains, that corresponds to the aromatic CH band detected in molecular clouds. Our results indicate that the common form for PAHs in the interstellar medium is as rings having one or more aliphatic side chains. The proportion of side chains increases as excitation decreases, so that the overall composition of substituted PAHs in the DISM approaches that of hydrogenated amorphous carbon.
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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 | 0.001 | 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".