Abstract The proposed Circular Electron Positron Collider (CEPC) is expected to provide adequate events around the Z boson mass pole, allowing high precision determination on the effective weak mixing angle. Specifically, one can acquire large data samples of the Z bb Z → b b ¯, Z cc Z → c c ¯ and Z ss Z → s s ¯ events with high purity, even though the efficiencies of the jet tagging are limited to ensure a good separation between different flavors. According to recent studies of the detector and reconstruction algorithms, with the new jet tagging method at the CEPC detector which gives a purity of 99. 9\% 99. 9 % for the bb b b ¯ and cc c c ¯ samples and 97\% 97 % for the ss s s ¯ sample, the corresponding uncertainties on the effective weak mixing angle determined from those samples are better than 10^-4 10 - 4 using data collected within 1 month. It allows high precision determinations of the effective weak mixing angle from different quark flavors especially for c and s quarks, which is essential to the standard model global test and potential new physics searches.
赵 et al. (Mon,) studied this question.