The design and performance of the wheel systems in the common foreoptics of the ELT METIS
Bibliographic record
Abstract
The Mid-infrared ELT Imager and Spectrograph (METIS) is one of the first light instruments for the Extremely Large Telescope (ELT) and will cover the thermal- and mid-infrared (3–13 μm). With the single conjugate adaptive optics (SCAO) system, it will enable high contrast imaging and integral field unit (IFU) spectroscopy (R ~ 100 000) at the diffraction limit of the ELT. Inside the METIS cryostat, it has a modular design and is composed of the common fore optics (CFO), the imager (IMG), the SCAO, and the L and M band integral field spectrograph (LMS). The components are cooled down to around 60K, or lower for the detectors, during the operation to reduce the background. In the CFO of METIS, four wheels are inserted in the optical path including the atmospheric dispersion corrector (ADC) wheel, the pupil plane one (PP1) wheel, the focal plane two (FP2) wheel and the LMS pickoff wheel. The PP1 wheel and the ADC wheel are located near the first pupil plane while the other two wheels are at the second focal plane. These wheels accommodate the optics, slits, masks and filters for various operation modes of METIS. In each wheel, common cartridges are designed to hold the optical elements to facilitate an easy exchange between them. High positioning repeatability is required for some of the optics. We will report the design and the initial integration and tests of the wheels in this paper.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.003 |
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".