The 7.5 Magnitude Limit Sample of Bright Short‐Period Binary Stars. I. How Many Contact Binaries Are There?
Bibliographic record
Abstract
A sample of bright contact binary stars (W UMa type or EW, and related: with β Lyr light curves, EB, and ellipsoidal, ELL—in effect, all but the detached, EA) to the limit of V max = 7.5 mag is deemed to include all discoverable short‐period ( P <1 day) binaries with photometric variation larger than about 0.05 mag. Of the 32 systems in the final sample, 11 systems have been discovered by the Hipparcos satellite. The combined spatial density is evaluated at (1.02 ± 0.24) × 10 -5 pc -3 . The relative frequency of occurrence (RFO), defined in relation to the main‐sequence stars, depends on the luminosity. An assumption of RFO ≃1/500 for M V > + 1.5 is consistent with the data, although the number statistics is poor with the resulting uncertainty in the spatial density and the RFO by a factor of about 2. The RFO rapidly decreases for brighter binaries to a level of 1/5000 for M V < + 1.5 and to 1/30,000 for M V < + 0.5. The high RFO of 1/130, previously determined from the deep OGLE‐I sample of disk population W UMa type systems toward Baade's window, is inconsistent with and unconfirmed by the new results. Possible reasons for the large discrepancy are discussed. They include several observational effects but also a possibility of a genuine increase in the contact‐binary density in the central parts of the Galaxy.
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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 | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.002 |
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".