Simulation studies for the LHC long-range beam-beam compensators

The performance of the Large Hadron Collider (LHC) and its minimum crossing angle are limited by long-range beam-beam collisions. Wire compensators can mitigate part of the long-range effects and may allow for smaller crossing angles, smaller β*, or higher beam intensity. A prototype long-range wire compensator should be installed in the LHC by 2014/15. We report simulation studies examining and comparing the efficiency of the wire compensation, in terms of tune footprint or dynamic aperture, at various candidate locations, with different wire shapes, and for varying transverse distance from the beam

MD1787 - LHC TDI tune shift measurement at injection

This report summarizes the results of the backup activity performed after cancellation of the MD1787. This MD was originally conceived to measure the instability growth rate versus chromaticity and damper settings at injections energy in the LHC, but, due to an RFQ issue in the Linac2 followed by an issue with the LHC cryogenic system, the original plan could not be executed. As a short backup activity on the available time given by the daylight saving on 30th October 2016 and the kind cooperation with other LHC MD users, it was decided to characterize with beam the TDI impedance