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

## TL;DR

This paper predicts the angular distribution coefficients of Z and W bosons produced in electron-positron collisions at 240 GeV, providing a basis for precise electroweak tests at the CEPC with reduced background.

## Contribution

It presents detailed predictions of angular coefficients in various polarization frames for Z and W bosons at CEPC, enhancing the potential for precise electroweak measurements.

## Key findings

- Angular coefficients depend on cosθ in different polarization frames.
- Predictions show improved measurement accuracy at CEPC due to lower background.
- Provides a method for testing electroweak production mechanisms and new physics effects.

## Abstract

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.