Nov 22 – 25, 2021
CERN
Europe/Zurich timezone

E-cloud, scrubbing and heat load after LS2 (20' + 10')

Nov 25, 2021, 9:30 AM
30m
500/1-001 - Main Auditorium (CERN)

500/1-001 - Main Auditorium

CERN

200
Show room on map

Speaker

Lotta Mether (CERN)

Description

In Run 2, routine LHC operation was done for the first time with 25 ns bunch spacing, leading to an increased electron cloud production. Although significant mitigation through beam-induced scrubbing was achieved, electron cloud affected beam stability and quality throughout the run. In addition, strong heat loads were generated on the beam screens of the superconducting magnets, with a large variation between magnets and arcs, in some cases approaching the nominal cooling capacity delivered by the corresponding cryogenic plant. In view of measurements, studies and interventions performed during Run 2 and the following Long Shutdown 2, the prospects for electron cloud effects during Run 3 will be discussed. The requirements for scrubbing, estimates of the required and available cooling capacity, as well as forecasts for electron cloud instabilities will be presented, considering also the availability of higher brightness beams after the completion of the LHC Injectors Upgrade.

Presentation materials