Toward precise<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mi>Q</mml:mi><mml:mrow><mml:mi mathvariant="normal">EC</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>values for the superallowed<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mn>0</mml:mn><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>→</mml:mo><mml:msup><mml:mn>0</mml:mn><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>β</mml:mi></mml:mrow></mml:math>decays of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>T</mml:mi><mml:mo>=</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:math>nuclides: The masses of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">Na</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>20</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">Al</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>24</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">P</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>28</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>, and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">Cl</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>32</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>
Bibliographic record
Abstract
High-precision measurements of superallowed ${0}^{+}\ensuremath{\rightarrow}{0}^{+}$ $\ensuremath{\beta}$ decays of $T=2$ nuclides such as $^{20}\mathrm{Mg}$, $^{24}\mathrm{Si}$, $^{28}\mathrm{S}$, and $^{32}\mathrm{Ar}$ can contribute to searches for physics beyond the standard model of particle physics if the ${Q}_{\mathrm{EC}}$ values are accurate to a few keV or better. As a step toward providing precise ${Q}_{\mathrm{EC}}$ values for these decays, the ground-state masses of the respective daughter nuclei $^{20}\mathrm{Na}$, $^{24}\mathrm{Al}$, $^{28}\mathrm{P}$, and $^{32}\mathrm{Cl}$ have been determined by measuring the ($^{3}\mathrm{He},t$) reactions leading to them with the $^{36}\mathrm{Ar}$($^{3}\mathrm{He},t$)$^{36}\mathrm{K}$ reaction as a calibration. A quadrupole-dipole-dipole-dipole (Q3D) magnetic spectrograph was used together with thin ion-implanted carbon-foil targets of $^{20}\mathrm{Ne}$, $^{24}\mathrm{Mg}$, $^{28}\mathrm{Si}$, $^{32}\mathrm{S}$, and $^{36}\mathrm{Ar}$. The masses of $^{20}\mathrm{Na}$ and $^{32}\mathrm{Cl}$ are found to be in good agreement with the values from the 2003 Atomic Mass Evaluation (AME03) [G. Audi, A. H. Wapstra, and C. Thibault, Nucl. Phys. A 729, 337 (2003)], and the precision has been improved by a factor of 6 in both cases. The masses of $^{24}\mathrm{Al}$ and $^{28}\mathrm{P}$ are found to be higher than the values from AME03 by 9.5 keV ($3.2\ensuremath{\sigma}$) and 11.5 keV ($3.6\ensuremath{\sigma}$), respectively, and the precision has been improved by a factor of 2.5 in both cases. The new $^{32}\mathrm{Cl}$ mass is used together with the excitation energy of its lowest $T=2$ level and the mass of $^{32}\mathrm{Ar}$ to derive an improved superallowed ${Q}_{\mathrm{EC}}$ value of 6087.3(22) keV for this case. The effects on quantities related to standard-model tests including the $\ensuremath{\beta}$-$\ensuremath{\nu}$ correlation coefficient $a$ and the isospin-symmetry-breaking correction ${\ensuremath{\delta}}_{C}$ are examined for the $A=32$ case.
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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 | 0.013 | 0.030 |
| Meta-epidemiology (narrow) | 0.005 | 0.006 |
| Meta-epidemiology (broad) | 0.003 | 0.006 |
| Bibliometrics | 0.005 | 0.005 |
| Science and technology studies | 0.003 | 0.003 |
| Scholarly communication | 0.018 | 0.025 |
| Open science | 0.009 | 0.010 |
| Research integrity | 0.005 | 0.013 |
| Insufficient payload (model declined to judge) | 0.177 | 0.211 |
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".