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Bibliographic record
Abstract
We have searched for flavor-changing neutral current decays and lepton-number-violating decays of ${D}^{+}$ and ${D}_{s}^{+}$ mesons to final states of the form ${h}^{\ifmmode\pm\else\textpm\fi{}}{e}^{\ensuremath{\mp}}{e}^{+}$, where $h$ is either $\ensuremath{\pi}$ or $K$. We use the complete samples of CLEO-c open-charm data, corresponding to integrated luminosities of $818\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ at the center-of-mass energy ${E}_{\mathrm{CM}}=3.774\text{ }\text{ }\mathrm{GeV}$ containing $2.4\ifmmode\times\else\texttimes\fi{}{10}^{6}$ ${D}^{+}{D}^{\ensuremath{-}}$ pairs and $602\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ at ${E}_{\mathrm{CM}}=4.170\text{ }\text{ }\mathrm{GeV}$ containing $0.6\ifmmode\times\else\texttimes\fi{}{10}^{6}$ ${D}_{s}^{*\ifmmode\pm\else\textpm\fi{}}{D}_{s}^{\ensuremath{\mp}}$ pairs. No signal is observed in any channel, and we obtain 90% confidence level upper limits on branching fractions $\mathcal{B}({D}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{e}^{+}{e}^{\ensuremath{-}})<5.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $\mathcal{B}({D}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{e}^{+})<1.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $\mathcal{B}({D}^{+}\ensuremath{\rightarrow}{K}^{+}{e}^{+}{e}^{\ensuremath{-}})<3.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $\mathcal{B}({D}^{+}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{e}^{+}{e}^{+})<3.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $\mathcal{B}({D}_{s}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{e}^{+}{e}^{\ensuremath{-}})<2.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $\mathcal{B}({D}_{s}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{e}^{+})<1.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $\mathcal{B}({D}_{s}^{+}\ensuremath{\rightarrow}{K}^{+}{e}^{+}{e}^{\ensuremath{-}})<5.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, and $\mathcal{B}({D}_{s}^{+}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{e}^{+}{e}^{+})<1.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$.
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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 | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.003 |
| Science and technology studies | 0.002 | 0.000 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.018 | 0.005 |
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".