Angular distribution coefficients of Z(W) boson produced in e^+e^- collisions at sqrt{s}=240 GeV

At designed CEPC, similar to hadron collider, the angular distribution coefficients of decay lepton pair from produced Z(W) boson in $e^+ e^-$ collisions are predicted. Their dependence on $cos\theta_Z$($cos\theta_W$) are presented in four different polarization frame. Furthermore, the value of angular coefficients in different bins of $cos\theta_Z$ are presented in the C-S frame. In comparison to the case at hadron collider, better accurate measurement for $Z(W)$ is expected since there exists less background and $W$ could be reconstructed from it's leptonic decay channel. This work supply a way to precise test the electroweak production mechanism or some effect induced from new physics in the future measurements at the CEPC.