BRITE-Constellation photometry of π5 Orionis, an ellipsoidal SPB variable
Bibliographic record
Abstract
ABSTRACT Results of an analysis of the BRITE-Constellation photometry of the SB1 system and ellipsoidal variable π5 Ori (B2 III) are presented. In addition to the orbital light-variation, which can be represented as a five-term Fourier cosine series with the frequencies forb, 2forb, 3forb, 4forb, and 6forb, where forb is the system’s orbital frequency, the star shows five low-amplitude but highly significant sinusoidal variations with frequencies fi (i = 2, .., 5, 7) in the range from 0.16 to 0.92 d−1. With an accuracy better than 1σ, the latter frequencies obey the following relations: f2 − f4 = 2forb, f7 − f3 = 2forb, f5 = f3 − f4 = f7 − f2. We interpret the first two relations as evidence that two high-order ℓ = 1, m = 0 gravity modes are self-excited in the system’s tidally distorted primary component. The star is thus an ellipsoidal SPB variable. The last relations arise from the existence of the first-order differential combination term between the two modes. Fundamental parameters, derived from photometric data in the literature and the Hipparcos parallax, indicate that the primary component is close to the terminal stages of its main-sequence (MS) evolution. Extensive Wilson–Devinney modelling leads to the conclusion that best fits of the theoretical to observed light curves are obtained for the effective temperature and mass consistent with the primary’s position in the HR diagram and suggests that the secondary is in an early MS evolutionary stage.
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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 | 0.003 | 0.001 |
| Science and technology studies | 0.001 | 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) | 0.002 | 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".