Speaker
Qiyu Sha
Description
In the Circular Electron Positron Collider (CEPC), a measurement of the Higgs \textit{CP} mixing through $e^{+} e^{-} \rightarrow Z H \rightarrow l^{+} l^{-}(\mu^{+} \mu^{-} / e^{+} e^{-}) H(\rightarrow b \bar{b} / c \bar{c} / g g)$ process is presented, with $5.6\ \mbox{ab}^{-1}$ $e^{+} e^{-}$ collision data at the center-of-mass energy of $240\ \mathrm{GeV}$. In this study, the \textit{CP}-violating parameter $\hat{\alpha}_{A \tilde{Z}}$ is constrained between the region of $ -6.69\times 10^{-2}$ and $6.32 \times 10^{-2}$ and $\hat{\alpha}_{Z \tilde{Z}}$ between $-1.67 \times 10^{-2}$ and $1.65 \times 10^{-2}$ at $95\%$ confidence level. This study demonstrates the great potential of probing Higgs $CP$ properties at the CEPC.
