EPS-AG Sacherer Prize: Beam Optics Developments for SPS, RHIC, LHC, CLIC and ATF2

Highlights of linear and nonlinear optics studies are presented from various accelerators. At the LHC, optics correction is of critical importance to guarantee safe beam operation. Preparation for LHC opticsmeasurements and corrections has been a major activity during the last decade. In particular, SPS and RHIC have served as excellent research and development machines to test new techniques and instrumentation, such as the measurement of resonance driving terms with and without AC dipoles. Together with a meticulous field quality specification, a careful installation strategy and an elaborate magnet model, these efforts have paid off in the LHC, where a record low beta-beating for hadron colliders below 10% has been achieved. Looking further into the future, the performance of the Final Focus System (FFS) is of critical importance for a future linear collider like CLIC, since it determines the IP beam spot sizes. The large chromatic aberrations required the development of novel non-linear optimization methods. Such techniques have successfully increased the CLIC design luminosity by 70% and an experimental test has been proposed for ATF2 to halve the design IP beam spot sizes.