New Measurement of 39Ar Lifetime and Projected Sensitivities for Time-Varying Signals with the DEAP-3600 Detector
Bibliographic record
Abstract
DEAP-3600 is a single-phase dark matter experiment searching for direct detection of elastic nuclear scatters of the dark matter candidate, WIMPs, with 3279 kg of liquid argon.In addition to the elastic interaction of the dark matter, theories also predict the modulation in this signal rate with time which is not expected in the backgrounds in the experiment.Observing this modulation signal will extend the sensitivity of the WIMP search in the experiment.The DEAP detector has recorded more than 3 years of physics data, and the absolute stability of the detector over the time of data collection allows the analysis of event rates in the detector data, which complements many other interesting analyses, such as a precise measurement of the lifetime of the 39 Ar isotope.The 878 days of live time are used to measure the 39 Ar lifetime by fitting the trigger rates with a decay model describing the data.The result, the first measurement to directly observe the decay curve of 39 Ar, shows a lifetime of 438 ± 10 (stat) ± 8 (syst) years, in tension with the literature value of 388 ± 4 years.A detailed systematic study of the detector is also performed to understand data that will contribute to the sensitivity of the detector for the modulation of the nuclear signal.This study indicated the requirement of a detector threshold of 5 keV or less to observe the annual modulation in the nuclear recoil signal.The DEAP experiment would need to collect new data at this lower hardware threshold and a more complete understanding of the detector backgrounds would be required.
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 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 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".