Measurement of neutral pion photoproduction off the proton with the large acceptance electromagnetic calorimeter BGOegg
Bibliographic record
Abstract
Differential cross sections and photon beam asymmetries for the reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}p$ have been measured in the photon beam energy range of $1.3--2.4\phantom{\rule{4pt}{0ex}}\mathrm{GeV}$ and the ${\ensuremath{\pi}}^{0}$ polar angle range of $\ensuremath{-}1<cos{\ensuremath{\theta}}_{{\ensuremath{\pi}}^{0}}^{\mathrm{c}.\mathrm{m}.}<0.7$. The measurement has been done by using a large acceptance electromagnetic calorimeter in the SPring-8 LEPS2/BGOegg experiment. The results of the photon beam asymmetry in a wide ${\ensuremath{\pi}}^{0}$ polar angle range are new for the photon beam energies exceeding $1.9\phantom{\rule{4pt}{0ex}}\mathrm{GeV}$. None of the existing partial wave analysis models describe the observed asymmetries in the high energy region. The contribution of multipole amplitudes with an orbital angular momentum of 5 in the $\ensuremath{\pi}N$ system has been found to be important at these energies.
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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 | 0.001 | 0.001 |
| 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 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| 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".