Excited-state transition-rate measurements in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mrow/><mml:mn>18</mml:mn></mml:msup></mml:math>C
Bibliographic record
Abstract
Excited states in ${}^{18}$C were populated by the one-proton knockout reaction of an intermediate energy radioactive ${}^{19}$N beam. The lifetime of the first ${2}^{+}$ state was measured with the K\"oln/NSCL plunger via the recoil distance method to be $\ensuremath{\tau}({2}_{1}^{+})=22.4\ifmmode\pm\else\textpm\fi{}0.9{(\mathrm{stat})}_{\ensuremath{-}2.2}^{+3.3}(\mathrm{syst})$ ps, which corresponds to a reduced quadrupole transition strength of $B(E2;{2}_{1}^{+}\ensuremath{\rightarrow}{0}_{1}^{+})=3.{64}_{\ensuremath{-}0.14}^{+0.15}{(\mathrm{stat})}_{\ensuremath{-}0.47}^{+0.40}(\mathrm{syst})$ e${}^{2}$fm${}^{4}$. In addition, an upper limit on the lifetime of a higher-lying state feeding the ${2}_{1}^{+}$ state was measured to be $\ensuremath{\tau}<4.6$ ps. The results are compared to large-scale ab initio no-core shell model calculations using two accurate nucleon-nucleon interactions and the importance-truncation scheme. The comparison provides strong evidence that the inclusion of three-body forces is needed to describe the low-lying excited-state properties of this $A=18$ system.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".