Impedance reduction in the CERN SPS through element layout optimisation

The CERN accelerator complex is currently in its long shutdown while the LHC Injector Upgrade is being carried out. The upgrade includes, but is not limited to, the relocation of the beam dumping system; upgrade of the RF system; replacement of the electrostatic septa and impedance reduction. These major upgrades present an opportunity to perform additional impedance reduction in areas not normally modified due to the large amount of work being performed across the accelerator complex. In this paper, we look at the impedance minimization in the sections near the large aperture quadrupoles of the extraction regions in CERNs SPS. By optimising the locations of existing equipment and introducing a new, more impedance optimised type of bellows, significant reductions in the beam-coupling impedance can be achieved.