Bibliographic record
Abstract
This thesis presents some of the techniques used in designing the sector-focused magnet for the TRIUMF cyclotron. An empirical method is given for calculating the magnet pole tip shape required to contain a 500 MeV beam of H⁻ ions. The method is good only for small changes in the shape. In the test case, the generated pole tip had a spiral angle correct to within ±5 degrees, and a hill angle correct to ±1 degree. The average field was found to be isochronous to ±70 gauss. An empirical solution to the problem of finding the field inside the magnet air gap is also given. The magnetic field resulting from a given pole tip contour is calculated at a point on the median surface by finding the perpendicular distance from the point to the edge of the pole and comparing this to an experimentally measured curve of field against distance. Fields generated by this technique have their averages correct to within 70 gauss and flutter to within 8%. Again, previous knowledge of similar pole tips is assumed. The method and results of calculating the pole edge position tolerances for the latest model magnet are given. The field strengths inside the steel return yoke as obtained from a series of flux measurements are also presented. Finally, it is shown that a simple approximation to the magnetic circuit of the magnet predicts the coil induction required to an accuracy of only 25%.
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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| 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".