<i>Hubble Space Telescope</i>NICMOS Variability Study of Massive Stars in the Young Dense Galactic Starburst NGC 3603
Bibliographic record
Abstract
We have used the relatively long data string of the 1997–1999 NICMOS focus tests on NGC 3603 to extract ∼ J -band light curves for several hundred stars in the cluster core. Given the relatively modest photometric precision [σ( J ) ≥ 0.05 mag], we were able to isolate only a half-dozen variable candidates with peak-to-valley amplitudes above ∼0.2 mag. One of the variables is one of the two outstandingly brightest cluster members, A1, located in the very dense cluster center. A1 shows double eclipses on each orbital cycle, with the same period ( P = 3.7724 days) as found previously and independently in unresolved ground-based radial velocity variations of the Wolf-Rayet (WR) emission component in the central core of NGC 3603. Very rough best estimates for the masses of the components of A1 are in the range 30–90 M ⊙ for the brighter and more massive H-rich WR component (WN6ha) and 25–50 M ⊙ for its assumed O star companion. A more detailed study is urgently needed, given the potential for this extremely luminous system to harbor the most massive main-sequence star ever "weighed." Another variable, HST 12, escaped the original search, which was based on larger than average standard deviation. It is a probable field-star eclipsing variable with a moderately long period.
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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 | 0.002 |
| Science and technology studies | 0.001 | 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) | 0.001 | 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".