ARC-BPAC December 2025 (rehearsal)
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06:00
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06:20
Accelerator operation issues and how they have been addressed 20m
Issues
** Beam size increase due to beam-beam
** Small dynamic aperture (short Touschek lifetime)
** Low injection efficiency (2nd bunch control, orbit jitter, emittance increase at BT, beam-beam, emittance increase at a larger charge at Linac)
** Poor stability and reproducibility
** Lack of monitors
** SBL
Summary of the work during the last shutdown to address those issuesSpeaker: Kyo Shibata -
06:20
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06:35
Belle II operation issues and how they have been addressed 15m
Issues:
** Beam background (detector performance, detector life, DAQ stability)
** Detector damage by SBL
** Lack of on-site experts
Summary of the work during the last shutdown to address those issuesSpeaker: Katsuro Nakamura (KEK) -
06:35
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06:55
Accelerator operation status 20m
Confirmed improvement by the work during the last shutdown
Plan and result of 2025c run
Issues in 2025c and how they have been addressed
** Hardware troubles and recovery procedures
** Physics run time less than 50%
** Lower injection efficiency than 2024c
** Lower specific luminosity than 2024cSpeaker: Makoto Tobiyama -
06:55
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07:15
Accelerator operation plan 20m
How to achieve 1/ab and 1 x 10^35 /cm^2/s
** How to reach LER > 2.0 A and HER > 1.4 A, issues to be addressed to reach it, and how to address it.
** How to keep 80% of physics run time and how to improve the accelerator operation efficiency
Machine studies
Plan ahead for possible issues and contingenciesSpeaker: Gaku Mitsuka -
07:15
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07:35
Mitigation plan for beam backgrounds and SBLs 20m
- Collimator
- Faster beam abort
- PXD HV fast shutdown
- Belle II HV emergency shutdown interlock for machine failure
Speaker: Hiroyuki Nakayama (Belle (SuperKEKB Experiment)) -
07:35
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07:55
Belle II operation status & plan 20m
- Current status of the beam background, SBL, and DAQ
- How the countermeasures for the issues are functioning in the operation
or what improvements were confirmed during this run - Operation arrangements and expert staffing
- Further improvements or implementation of remaining countermeasures
- Detector studies
- Strategy or criteria to turn on PXD
Speaker: Kenta Uno (KEK)
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06:00
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06:20