Transparent Injection into Electron and Positron Accelerator Rings
Bibliographic record
Abstract
Particle accelerator rings utilize high energy particles for a broad range of scientific purposes. Synchrotron\nlight source facilities such as the Canadian Light Source (CLS) utilize radiation emitted by the acceleration\nof electrons in an electromagnetic trap called a storage ring to investigate many topics including agricultural,\nbiomedical, and materials science problems. Particle colliders like the planned Future Circular Collider\nelectron-positron machine (FCC-ee) also store a beam of accelerated particles in a collider ring. The difference\nis that the FCC-ee will also have a second beam traveling in the opposite direction. The two beams collide\nat interaction points (IPs) which are observed using very precise detectors. Colliders study the fundamental\nparticles’ structure and test the standard model, one goal of FCC-ee is to intensely study the Higg’s boson[1].\nIn both machines the particle beams travel in very high vacuum to minimize scattering off gas particles.\nHowever, the beams travel near the speed of light and traverse the nearly 100 km FCC-ee ring many thousands\nof times, and the much smaller 171 m CLS ring millions of times, per second. Thus, particle losses are\nnon-negligible and beam current decays over time. In a light source the intensity of radiation provided to\nexperiments is important for the quality of their measurements. In a collider the key value is luminosity, a\nmeasure of the rate of interactions between particles. Both these values depend on the beam current stored in\nthe rings and each machine benefits greatly from maintaining consistently high beam current. Thus, particles\nare regularly injected into the rings to prevent the beam current from decaying, called top-up injection.\nIn order to store new particles in an accelerator ring, pulsed magnets are used to steer the additional\nparticles into the machine. These magnets disturb the beam stored in the ring resulting in oscillation of the\nbeam after each injection. The intensity of light CLS provides modulates as the electron beam moves relative\nto experimental optics, affecting researcher’s data. Similarly, misalignment of the beams in a collider will\nreduce the luminosity. Ideally, injection would be transparent to the experiments, not disturbing the stored\nbeam. In practice transparent injection does not completely remove the disturbance but minimizes it.\nThis thesis presents my work on transparent top-up injection for CLS and FCC-ee. For the CLS I had the\nobjective of finding alternative injection schemes which could be implemented into the current CLS machine,\nand minimizing the post-injection transient oscillation of the stored beam. Simulation of several approaches\nachieved a reduction of the magnitude of post-injection stored beam oscillation by a factor of 50. However,\nthe large size of the injected beam at the CLS meant that the injection efficiency was insufficient for the\nalternative injection approach to be used in normal operations.\nFor FCC-ee my objectives were to develop magnet settings to allow for each of four proposed injection\napproaches. Further, I studied injection with the novel multipole kicker magnet design proposed for FCC-ee.\nSimulation of effects of the multipole kicker on the stored beam, and its sensitivity to misalignments and\nother errors showed that there is risk for instabilities of the beam potentially resulting in significant losses.\nThese studies led to a recommendation for the baseline injection scheme as the FCC-ee project continues.
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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 | 0.000 |
| 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".