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Bibliographic record
Abstract
Using data taken with the CLEO III detector at the Cornell Electron Storage Ring, we have investigated the direct photon spectrum in the decays $\ensuremath{\Upsilon}(1\mathrm{S})\ensuremath{\rightarrow}\ensuremath{\gamma}gg$, $\ensuremath{\Upsilon}(2\mathrm{S})\ensuremath{\rightarrow}\ensuremath{\gamma}gg$, $\ensuremath{\Upsilon}(3\mathrm{S})\ensuremath{\rightarrow}\ensuremath{\gamma}gg$. The latter two of these are first measurements. Our analysis procedures differ from previous ones in the following ways: (a) background estimates (primarily from ${\ensuremath{\pi}}^{0}$ decays) are based on isospin symmetry rather than a determination of the ${\ensuremath{\pi}}^{0}$ spectrum, which permits measurement of the $\ensuremath{\Upsilon}(2\mathrm{S})$ and $\ensuremath{\Upsilon}(3\mathrm{S})$ direct photon spectra without explicit corrections for ${\ensuremath{\pi}}^{0}$ backgrounds from, e.g., ${\ensuremath{\chi}}_{bJ}$ states, (b) we estimate the branching fractions with a parametrized functional form (exponential) used for the background, and c) we use the high-statistics sample of $\ensuremath{\Upsilon}(2\mathrm{S})\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}\ensuremath{\Upsilon}(1\mathrm{S})$ to obtain a tagged sample of $\ensuremath{\Upsilon}(1\mathrm{S})\ensuremath{\rightarrow}\ensuremath{\gamma}+X$ events, for which there are no QED backgrounds. We determine values for the ratio of the inclusive direct photon decay rate to that of the dominant three-gluon decay $\ensuremath{\Upsilon}\ensuremath{\rightarrow}ggg\text{ }\text{ }({R}_{\ensuremath{\gamma}}=B(gg\ensuremath{\gamma})/B(ggg))$ to be ${R}_{\ensuremath{\gamma}}(1\mathrm{S})=(2.70\ifmmode\pm\else\textpm\fi{}0.01\ifmmode\pm\else\textpm\fi{}0.13\ifmmode\pm\else\textpm\fi{}0.24)%$, ${R}_{\ensuremath{\gamma}}(2\mathrm{S})=(3.18\ifmmode\pm\else\textpm\fi{}0.04\ifmmode\pm\else\textpm\fi{}0.22\ifmmode\pm\else\textpm\fi{}0.41)%$, and ${R}_{\ensuremath{\gamma}}(3\mathrm{S})=(2.72\ifmmode\pm\else\textpm\fi{}0.06\ifmmode\pm\else\textpm\fi{}0.32\ifmmode\pm\else\textpm\fi{}0.37)%$, where the errors shown are statistical, systematic, and theoretical model dependent, respectively. Given a value of ${Q}^{2}$, one can estimate a value for the strong coupling constant ${\ensuremath{\alpha}}_{s}({Q}^{2})$ from ${R}_{\ensuremath{\gamma}}$.
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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) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.100 | 0.025 |
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".