LHC Project Seminar: FIDEL - The Field Description for the LHC

by Sammut, N. (AT-MTM and The University of Malta)

Thursday 14 Sept 2006, 14:15 → 15:15 Europe/Zurich

AT Auditorium (CERN)

The LHC needs a robust control system to compensate for the static and dynamic field variations in the main superconducting magnets. If these field changes are not corrected with high speed and precision, they may jeopardize the machine performance significantly. Unfortunately, a system solely based on beam feed-back may be too complex for precision compensation with the bandwidth required. The present baseline for the LHC therefore requires a system based on feed-forward control to reduce the burden on the beam based feed-back by forecasting what the field variations will be to within a residual error comparable to beam control requirements. This feed-forward control system is known as the FIeld DEscription for the LHC (FIDEL).

The core of FIDEL mainly consists of a static and dynamic field model extended by a set of scaling laws. These are based on the identification and physical decomposition of the effects that contribute to the total field in the magnet aperture of the LHC dipoles. Each effect is quantified using data obtained from series magnetic measurements, and modelled theoretically or empirically depending on the complexity of the physical phenomena involved.

This talk will present the main concepts and the recent developments of FIDEL and will also provide an evaluation of its accuracy and predictive capabilities.

Organiser(s): John Miles (AT-MAS)