CEPC Z-pole polarization design studies

In this paper, we give preliminary designs of beam polarization manipulations by inserting three different types of insertions in the Circular Electron-Positron Collider (CEPC) at center-of-mass energies of 91 GeV (Z-pole). With the wigglers in the collider ring, we can obtain 5% transverse polarization in 1.1 h for the precise energy measurement. To overcome depolarization effects as the beam energy rises from 10 GeV to 45.5 GeV in the booster ring, Siberian snakes based on helical magnets are adopted. Finally, for longitudinally polarized beam collisions, a schematic design of spin rotators based on solenoids in the collider ring is studied.

Automated summary

This paper presents preliminary designs of beam polarization manipulations in the CEPC, including using wigglers for transverse polarization, Siberian snakes for overcoming depolarization effects, and studying spin rotators based on solenoids for longitudinally polarized beam collisions.