CERN LHC Project Report 120 (1997),
presented at the IEEE Particle Accelerator Conference (session 7P-8), Vancouver, 1997
Summary of the Single-Beam Collective Effects in the LHC
F. Ruggiero, J.S. Berg, O. Brüning, F. Caspers, M. Morvillo, and M. D'Yachkov
May 1997
Abstract:
Single beam collective effects can limit the performance of the LHC and,
together with parasitic losses, impose constraints on the design of the
components of the LHC vacuum system.
Because of the large number of bunches in the LHC, coherent
losses and multibunch instability rise times generated by the
impedance items can be rather large. For example, the vacuum chambers
of the main experiments can lead to large parasitic losses and
a continuous feedback from the impedance calculations during their design
process is desirable.
We first summarise the current status
of the impedance model for the LHC and estimate rise times and
threshold currents for different instabilities.
In a second step,
we discuss possibilities of
controlling these instabilities,
using feedback systems and Landau damping.
F. Ruggiero
Wed May 21 17:11:35 1997