HE linac at 6 GHz RF
BC and EC for HE linac
Plans at FACET
Optimization updates
ECHO2D comparison
Structure length and RF design
RF PC design update
Dear all,
As you may have seen from the FCC Week 2025 presentation of Luca and from discussions with us, we would like to move forward with investigations into the feasibility of using 5 ns non-uniform filling schemes at lower bunch intensities to mitigate the electron cloud effect.
In this context, we would like to ask whether it would be possible for you to evaluate the two options we have selected, as described in the attached slides. Please feel free to reach out if you need any clarifications or additional information. More details and the motivation behind this request can be found in Luca’s presentation from FCC Week:
https://indico.cern.ch/event/1408515/contributions/6515085/attachments/3071179/5433274/2025_05_20_FCC_week.pdf
The goal is to assess the beam stability along the full injector chain and identify any potential show-stoppers for this bunch spacing.
We can then discuss the results together to assess whether these options could represent a viable solution for FCC-ee. The plan would be to first organize an informal e-cloud meeting to review your feedback and comments on this proposal. If we conclude that there are no major showstoppers, we would then arrange a dedicated FCC-ee Accelerator Design meeting to further discuss the topic.
Thank you very much for your availability and feedback.
Best regards,
Tatiana, Luca and Lotta
