Optics control in 2016

Abstract

In 2016 the fi-functions at the interaction points of ATLAS and CMS have been squeezed down to 0.4 m. This is below the design fi" = 0.55 m at 7 TeV and has been instrumental to surpass the design luminosity. Even though the fl-beating for the virgin machine was above 100% the corrections reduced it to an rms B-beating below 1% at the two main experiments and below 2% rms around the ring. These results are presented together with the fl-beating deriving from the crossing angles in combination with the sextupolar errors in the IRs. A way to correct the errors using sextupo-lar correctors is referenced and how this could be integrated in the commissioning is outlined. Furthermore. the progress towards an automatic coupling correction is described