Integrated luminosity measurement at CEPC

Abstract

The very forward region is one of the most challenging regions to instrument at a future $e^{+}{e}^{-}$ collider. At CEPC, machine-detector interface includes, among others, a calorimeter dedicated for precision measurement of the integrated luminosity at a permille level or better. Here we review a feasibility of such precision, from the point of view of luminometer mechanical precision and positioning, beam-related requirements and physics background.A method of the effective center-of-mass determination from $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}$, initially proposed for FCC, is also discussed for the CEPC beams.

Talk presented at the International Workshop on Future Linear Colliders (LCWS2021), 15-18 March 2021. C21-03-15.1. arXiv admin note: text overlap with arXiv:2010.15061, arXiv:2002.03661