Investigating Ca<scp>ii</scp>Emission in the RS Canum Venaticorum Binary ER Vulpeculae Using the Broadening Function Formalism
Bibliographic record
Abstract
The synchronously rotating G stars in the detached, short-period (0.7 days), partially eclipsing binary ER Vul are the most chromospherically active solar-type stars known. We have monitored activity in the Ca II H and K reversals for almost an entire orbit. Rucinski's broadening function formalism allows the photospheric contribution to be objectively subtracted from the highly blended spectra. The power of the broadening function technique is also demonstrated by the good agreement of radial velocities with those measured by others from less crowded spectral regions. In addition to strong Ca II emission from the primary and secondary, there appears to be a high-velocity stream flowing onto the secondary, where it stimulates a large active region on the surface 30°–40° in advance of the subbinary longitude. A model light curve with a spot centered on the same longitude also gives the best fit to the observed light curve. A flare with ∼13% more power than at other phases was detected in one spectrum. We suggest that ER Vul may offer a magnified view of the more subtle chromospheric effects synchronized to planetary revolution seen in certain 51 Peg–type systems.
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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 | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| 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".