Differential Cross Section and Photon-Beam Asymmetry for the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mover accent="true"><mml:mrow><mml:mi>γ</mml:mi></mml:mrow><mml:mrow><mml:mo stretchy="false">→</mml:mo></mml:mrow></mml:mover><mml:mi>p</mml:mi><mml:mtext> </mml:mtext><mml:mo stretchy="false">→</mml:mo><mml:mtext> </mml:mtext><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi mathvariant="normal">Δ</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo stretchy="false">(</mml:mo><mml:mn>1232</mml:mn><mml:mo stretchy="false">)</mml:mo></mml:mrow></mml:math> Reaction at Forward <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>π</mml:mi><mml:mo>−</mml:mo></mml:msup></mml:math> Angles for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>E</mml:mi></mml:mrow><mml:mrow><mml:mi>γ</mml:mi></mml:mrow></mml:msub><mml:mo>=</mml:mo><mml:mn>1.5</mml:mn><mml:mo>–</mml:mo><mml:mn>2.95</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi></mml:mrow></mml:math>
Bibliographic record
Abstract
Differential cross sections and photon-beam asymmetries for the $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\gamma}}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\mathrm{\ensuremath{\Delta}}}^{++}(1232)$ reaction have been measured for $0.7<\mathrm{cos}{\ensuremath{\theta}}_{\ensuremath{\pi}}^{\mathrm{c}.\mathrm{m}.}<1$ and ${E}_{\ensuremath{\gamma}}=1.5--2.95\text{ }\text{ }\mathrm{GeV}$ at SPring-8/LEPS. The first-ever high statistics cross-section data are obtained in this kinematical region, and the asymmetry data for $1.5<{E}_{\ensuremath{\gamma}}(\mathrm{GeV})<2.8$ are obtained for the first time. This reaction has a unique feature for studying the production mechanisms of a pure $u\overline{u}$ quark pair in the final state from the proton. Although there is no distinct peak structure in the cross sections, a non-negligible excess over the theoretical predictions is observed at ${E}_{\ensuremath{\gamma}}=1.5--1.8\text{ }\text{ }\mathrm{GeV}$. The asymmetries are found to be negative in most of the present kinematical regions, suggesting the dominance of $\ensuremath{\pi}$ exchange in the $t$ channel. The negative asymmetries at forward meson production angles are different from the asymmetries previously measured for the photoproduction reactions producing a $d\overline{d}$ or an $s\overline{s}$ quark pair in the final state. Advanced theoretical models introducing nucleon resonances and additional unnatural-parity exchanges are needed to reproduce the present data.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.011 | 0.011 |
| Meta-epidemiology (narrow) | 0.008 | 0.015 |
| Meta-epidemiology (broad) | 0.003 | 0.016 |
| Bibliometrics | 0.004 | 0.009 |
| Science and technology studies | 0.013 | 0.013 |
| Scholarly communication | 0.013 | 0.011 |
| Open science | 0.016 | 0.014 |
| Research integrity | 0.015 | 0.013 |
| Insufficient payload (model declined to judge) | 0.602 | 0.012 |
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; both teacher heads agree on what is shown here.
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".