Bibliographic record
Abstract
We have used deep optical and infrared imaging to study the E/S0 galaxies in the central regions of eight intermediate-redshift (0.40 < z < 0.48) clusters. We find that the luminosity function for red galaxies with -25.6 < M V < -17.6 (Ω M = 0.2, Ω Λ = 0, and H 0 = 50 km s -1 Mpc -1 ) in the clusters' red sequence are well described by a Schechter function for all clusters. In spite of the fact that the clusters span a wide range in richness and X-ray luminosities, all the cluster luminosity functions are consistent with a single value for their characteristic magnitude ( M *). The value of M * at z = 0.45 appears brighter than that observed in local clusters (Δ M = -0.94 ± 0.41), in agreement with models of passive evolution and with studies of surface brightness and fundamental plane at these redshifts. We have also observed a color change in the rest-frame ( U - V ) and ( V - H ) colors, as compared to local galaxies. We find that most of the popular simple stellar population models fail to account for this color evolution vector with the discrepancy mainly in the optical-infrared color. However, the rest-frame ( U - V ) color change seems to be well described by these simple models, and it can be used to estimate the ages of the stellar populations in these galaxies. We find that the stars in the E/S0 galaxies at z = 0.45 must have been formed at z ≳ 1 for solar or supersolar metallicities.
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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 | 0.002 |
| 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 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.009 | 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".