Carbon K-edge polarimetry with Cr/Sc multilayers
Bibliographic record
Abstract
We investigate the polarization changes simultaneously occurring with intensity changes due to carbon contamination of optical components at two plane grating beam lines PGM-1 and PGM-2 at BESSY II. The two beam lines are very similar to each other and connect to the same APPLE II type undulator UE56/2. The spectra measured with initial horizontal and vertical polarization differ for the two beam lines. For polarimetry measurements the BESSY 8-axis polarimeter is equipped with a Cr/Sc multilayer in transmission as phase retarder and a Cr/Sc reflecting multilayer operating near the Brewster angle as analyzer. The polarimetry results also differ for the two beam lines. Only at PGM-2 we observe no decline of the degree of polarization within experimental errors i.e. the degree of polarization at PGM-2 is always found P > 0.96. We find big changes of the polarization which rapidly vary across the carbon edge. A tentative interpretation predicts the orientation of the dipoles in the contaminating carbon layers. Circular polarization is largely recovered (80% and higher) at PGM-2 thru out the carbon edge by setting the undulator shift to approximately compensate the polarizing properties of the beam line.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 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".