High-Luminosity CLIC Studies

In 2018 the CLIC study submitted a number of reports as input to the update of European Strategy for Particle Physics, among them a detailed description of the CLIC accelerator complex and its performance. These reports, which include references to comprehensive background documents, are available at http://clic.cern/european-strategy. During 2019 additional questions have come up which concern the performance of CLIC in various operating conditions. These are: what are the margins for increasing the baseline luminosity performance by further improving the beam quality at the interaction point; is there a possibility of doubling the luminosity by operating at 100 Hz instead of 50 Hz; what is the performance of CLIC running at the Z-pole and what is the expected performance for gamma-gamma collisions? These questions are addressed in this note.