100 km CEPC parameters and lattice design

Abstract

In this paper, a consistent calculation method for the CEPC parameter choice with a crab waist scheme is reported. A crosscheck of luminosity with beam–beam simulations has been done. With this new scheme, a higher Higgs luminosity (+[Formula: see text]170%) can be reached while keeping Pre-CDR beam power or the beam power (19 MW) can be reduced while keeping the same Pre-CDR luminosity. CEPC is compatible with W and Z experiment. The luminosity for Z is at the level of [Formula: see text]. Requirement for energy acceptance of Higgs has been reduced to 1.5% by enlarging the ring to 100 km. The arc optics and the Final Focus System (FFS) with crab sextupoles have been designed, and also some primary Dynamic Aperture (DA) results were introduced.

CEPC cost model study and circumference optimization

“…A general method has been developed to optimize the parameters of a circular 𝑒 + 𝑒 − Higgs factory by using analytical expressions for the maximum beam-beam parameter and the beamstrahlung beam lifetime, starting from a given design goal and technical constraints [28,30,31]. A parameter space has been explored.…”

Status and Prospects of e+e- Factories

“…Two circular colliders are being studied to deliver data on a large energy range: the FCCee [7] at CERN, from 45 to 175 GeV/beam, and the CEPC [9] at IHEP, from 45 to 120 GeV/beam. Both rely on Super Conducting cavities to cope with the large power consumption.…”

“…9 left) [9]. For the Higgs operation mode, the RF cavities will be in common between the two beams, with bunches filled only in half of the rings, while for the W and Z production there will be independent RF cavities (650 MHz) and all bunches will be filled (see Fig.…”

“…A "super" BFactory, SuperKEKB in Japan [6], is in the commissioning phase. At much higher energy larger and more ambitious projects, circular and linear, are being proposed at CERN (FCC-ee [7], CLIC [8]), China (CEPC) [9] and Japan (ILC) [10].…”