Self-Correlation Analysis of the Photometric Variability of T Tauri Stars. II. A Survey
Bibliographic record
Abstract
We have used archival CCD data, Fourier analysis, and self-correlation analysis to study the photometric time variability of 162 T Tauri stars and related objects, including Herbig Ae/Be stars. Many show periodic variability, presumably due to rotation of a spotted star in most cases. For the nonperiodic stars, we have estimated an upper limit to the periodic variability. We have also analyzed 26 stars suspected to have periods longer than about 10 days. Of these 26 stars, at least 14 have periods significantly longer than 10 days; their variability may be due to processes in the disk, or the effect of a companion, since most (but not all) T Tauri stars have rotational periods less than this value. For a few of the rotational variables, namely AA Tau, DK Tau, DL Tau, DN Tau, GK Tau, GM Aur, Rox 29, V1121 Oph, V410 Tau, and V649 Ori, we have found long-term variability of the amplitude, presumably due to activity cycles; the time scales are 1500–4000 days.
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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 | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".