Search For Invisible Nucleon Decay in SNO+ With Improved Sensitivity
Bibliographic record
Abstract
The water phase of the SNO+ (Sudbury Neutrino Observatory) experiment has completed after the collection of ~305 days of total livetime worth of data, divided into two main sets. The effective concentration of U-238 and Th-232 in the water was determined using in situ analysis to be, for the second set of data, gU/gH2O: (3.64 +/- 0.74_(stat) + 1.28_(syst) - 0.99_(syst) x 10^-15 and gTh/gH2O: (3.08 +/- 3.22_(stat) + 1.60_(syst) - 5.00_(syst) ) x 10^-16. The water data can also been used to search for ``invisible" modes of nucleon decay, and a previous SNO+ publication set world-leading limits on relevant nucleon and dinucleon decay modes except neutron and dineutron decay. This thesis presents a re-analysis of the ``invisible" neutron decay mode of that first set of data, which reoptimizes the fiducial volume and develops an improved treatment of the dominant energy systematic uncertainties. This leads to a world-leading lower limit on the ``invisible" neutron decay lifetime of 6.91 x 10^29 years. A sensitivity analysis shows that including the second set of data that has lower backgrounds is expected to yield a lower limit on the neutron decay lifetime of 1.57 x 10^30 years, further improving the result.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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".