An overview of the LHC Transverse Diagnostics Systems

The unprecedented intensity and energy of the LHC proton beams will require an excellent control of the transverse beam dynamics in order to limit particle loss in the superconducting systems. Due to restricted tolerances of the machine protection system and a tight beam emittance blow-up budget only small beam excitation is allowed, making precise measurements of the transverse beam parameters very challenging. This overview outlines the systems measuring the tune, chromaticity and betatron coupling of the LHC beams, referred to in the paper as the transverse diagnostic systems. As manual correction of the parameters may reach its limit with respect to required precision and expected time scales, the LHC is the first proton collider that can be safely and reliably operated only with automatic feedback systems for controlling transverse beam dynamics. An outline of these feedback systems is also presented.

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