Speaker
Description
The Compact Linear Accelerator for Research and Applications (CLARA) at Daresbury Laboratory has recently undertaken an upgrade of its photocathodes from using a copper emission surface to using caesium telluride (Cs2Te).
During the conditioning of the first Cs2Te cathode a significant number of RF breakdowns were detected, and so that cathode was replaced; subsequent inspection of the cathode identified a number of surface defects. To better study
the second cathode, a diagnostic camera was used to collect images of the surface in situ during RF conditioning; the frequent formation over time of surface defects was observed. In this paper we present a statistical analysis of the breakdown events and surface image data, utilizing cross-correlation of the signal derivatives to account for cumulative trends. The analysis reveals a correlation between the rate of defect formation and the incidence of RF breakdowns, with
a Pearson coefficient of 𝑟 = 0.59 at zero time lag. These results provide quantitative evidence that RF breakdown events are the likely driver of surface morphology changes on Cs2Te cathodes.
| Presenting Author | Hugh Churn |
|---|---|
| Is the Presenting Author a PhD Student or Early Career Scientist ? | No |
| Area of research | Accelerator technology (including magnets) |