First measurement of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>B</mml:mi><mml:mo>(</mml:mo><mml:mi>E</mml:mi><mml:mn>2</mml:mn><mml:mo>;</mml:mo><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:msup><mml:mn>2</mml:mn><mml:mo>−</mml:mo></mml:msup><mml:mspace width="4pt"/><mml:mo>→</mml:mo><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msup><mml:mn>2</mml:mn><mml:mo>−</mml:mo></mml:msup></mml:mrow></mml:math>) transition strength in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>Be</mml:mi><mml:mprescripts/><mml:none/><mml:mn>7</mml:mn></mml:mmultiscripts></mml:math>: Testing <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>a</mml:mi><mml:mi>b</mml:mi><mml:mspace width="4pt"/><mml:mi>i</mml:mi><mml:mi>n</mml:mi><mml:mi>i</mml:mi><mml:mi>t</mml:mi><mml:mi>i</mml:mi><mml:mi>o</mml:mi></mml:mrow></mml:math> predictions for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>A</mml:mi><mml:mo>=</mml:mo><mml:mn>7</mml:mn></mml:mrow></mml:math> nuclei
Bibliographic record
Abstract
Electromagnetic observables are able to give insight into collective and emergent features in nuclei, including nuclear clustering. These observables also provide strong constraints for ab initio theory, but comparison of these observables between theory and experiment can be difficult due to the lack of convergence for relevant calculated values, such as $E2$ transition strengths. By comparing the ratios of $E2$ transition strengths for mirror transitions, we find that a wide range of ab initio calculations give robust and consistent predictions for this ratio. To experimentally test the validity of these ab initio predictions, we performed a Coulomb excitation experiment to measure the $B(E2;3/{2}^{\ensuremath{-}}\ensuremath{\rightarrow}1/{2}^{\ensuremath{-}})$ transition strength in $^{7}\mathrm{Be}$ for the first time. A $B(E2;3/{2}^{\ensuremath{-}}\ensuremath{\rightarrow}1/{2}^{\ensuremath{-}})$ value of $26{(6)}_{\mathrm{stat}}{(3)}_{\mathrm{syst}}\phantom{\rule{0.16em}{0ex}}{e}^{2}{\mathrm{fm}}^{4}$ was deduced from the measured Coulomb excitation cross section. This result is used with the experimentally known $^{7}\mathrm{Li}\phantom{\rule{4pt}{0ex}}B(E2;3/{2}^{\ensuremath{-}}\ensuremath{\rightarrow}1/{2}^{\ensuremath{-}})$ value to provide an experimental ratio to compare with the ab initio predictions. Our experimental value is consistent with the theoretical ratios within $1\ensuremath{\sigma}$ uncertainty, giving experimental support for the value of these ratios. Further work in both theory and experiment can give insight into the robustness of these ratios and their physical meaning.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.015 | 0.014 |
| Meta-epidemiology (narrow) | 0.009 | 0.017 |
| Meta-epidemiology (broad) | 0.004 | 0.018 |
| Bibliometrics | 0.005 | 0.011 |
| Science and technology studies | 0.015 | 0.015 |
| Scholarly communication | 0.013 | 0.012 |
| Open science | 0.019 | 0.018 |
| Research integrity | 0.016 | 0.016 |
| Insufficient payload (model declined to judge) | 0.270 | 0.016 |
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".