Model Atmosphere Analysis of the Weakly Magnetic DZ White Dwarf G165‐7
Bibliographic record
Abstract
A reanalysis of the strongly metal-blanketed DZ white dwarf G165-7 is presented. An improved grid of model atmospheres and synthetic spectra is used to analyze BVRI , JHK , and ugriz photometric observations as well as a high-quality Sloan Digital Sky Survey spectrum covering the energy distribution from 3600 to 9000 Å. The detection of splitting in several lines of Ca, Na, and Fe, suggesting a magnetic field of B s ~ 650 kG, is confirmed by spectropolarimetric observations that reveal as much as ±7.5% circular polarization in many of the absorption lines, most notably Na, Mg, and Fe. Our combined photometric and spectroscopic fit yields T eff = 6440 K, log g = 7.99, log(H/He) = -3.0, and log(Ca/He) = -8.1. The other heavy elements have solar ratios with respect to Ca, with the exception of Na and Cr, which had to be reduced by a factor of 2 and 3, respectively. A crude polarization model based on the observed local spectral flux gradient yields a longitudinal field of 165 kG, consistent with the mean surface field inferred from the Zeeman splitting. The inclusion of this weak magnetic field in our synthetic spectrum calculations, even in an approximate fashion, is shown to improve our fit significantly.
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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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| 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".