HL-LHC Hollow Electron Lens Integration using MERLIN

The C++ accelerator physics library MERLIN has been developed for LHC collimation. Recently MERLIN has been upgraded to provide a robust tool for HL-LHC collimation, including the treatment of composite materials, and a hollow electron lens process. The HEL is being considered as a collimation enhancer for the HL-LHC. We use MERLIN to perform case studies of integrating a HEL at different points in the lattice, and in doing so, demonstrate recent updates to the code. Of particular interest when integrating is the roundness of the beam (in real space) at the position of the HEL, and the effect that this has on collimation enhancement