Precision pion-proton elastic differential cross sections at energies spanning the Δ resonance
Bibliographic record
Abstract
A precision measurement of absolute ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}p$ elastic differential cross sections at incident pion laboratory kinetic energies from ${T}_{\ensuremath{\pi}}=141.15$ to 267.3 MeV is described. Data were obtained detecting the scattered pion and recoil proton in coincidence at 12 laboratory pion angles from $55\ifmmode^\circ\else\textdegree\fi{}$ to $155\ifmmode^\circ\else\textdegree\fi{}$ for ${\ensuremath{\pi}}^{+}p$ and six angles from $60\ifmmode^\circ\else\textdegree\fi{}$ to $155\ifmmode^\circ\else\textdegree\fi{}$ for ${\ensuremath{\pi}}^{\ensuremath{-}}p.$ Single arm measurements were also obtained for ${\ensuremath{\pi}}^{+}p$ energies up to 218.1 MeV, with the scattered ${\ensuremath{\pi}}^{+}$ detected at six angles from $20\ifmmode^\circ\else\textdegree\fi{}$ to $70\ifmmode^\circ\else\textdegree\fi{}.$ A flat-walled, supercooled liquid hydrogen target and solid ${\mathrm{CH}}_{2}$ targets were used. The data are characterized by small uncertainties, $\ensuremath{\sim}1--2%$ statistical and $\ensuremath{\sim}1--1.5%$ normalization. The reliability of the cross section results was ensured by carrying out the measurements under a variety of experimental conditions to identify and quantify the sources of instrumental uncertainty. Our lowest- and highest-energy data are consistent with overlapping results from TRIUMF and LAMPF. In general, the Virginia Polytechnic Institute SM95 partial-wave analysis (PWA) solution describes our data well, but the older Karlsruhe-Helsinki PWA solution KH80 does not.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| 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) | 0.000 | 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 teacher head, 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".