论文标题
测量有效的弱混合角在CEPC处
Measurement of the effective weak mixing angle at the CEPC
论文作者
论文摘要
我们介绍了对有效弱混合角参数的测量（$ \ sin^2θ^{\ ell} _ \ text {eff} $）在圆形电子potitron Collider（CEPC）上的测量。作为基本物理参数，$ \ sin^2θ^{\ ell} _ \ text {eff} $不仅在标准模型Electroweak扇区的全局测试中都扮演关键角色，而且还可以限制高能领域的标准模型超出标准模型的潜力。 CEPC提议在Z Boson质量杆上以高的亮度亮度进行两年的运行时间，从而为大型数据样本提供了$ 4 \ times 10^{12} $ $ z $ $ z $的候选者。它允许对$ \ sin^2θ^{\ ell} _ \ text {eff} $进行高精度测量。它不仅将提高$ \ sin^2θ^\ ell_ \ text {eff} $实验确定的总体精度，可与两环辐射校正的理论计算的序列相提并论，而且还提供了不同最终状态之间的直接比较。在本文中，我们还研究了高质量区域的$ \ sin^2θ^{\ ell} _ \ text {eff} $的测量。通过获取一个月的数据，$ \ sin^2θ^{\ ell} _ \ text {eff} $的精度为130 gev的$ b $ quark最终状态为0.00010，这将是对$ \ sin^2θ^{\ ell} _ \ fext} $的重要实验观察。
We present a study of the measurement of the effective weak mixing angle parameter ($\sin^2θ^{\ell}_\text{eff}$) at the Circular Electron Positron Collider (CEPC). As a fundamental physics parameter, $\sin^2θ^{\ell}_\text{eff}$ plays a key role not only in the global test of the standard model electroweak sector, but also in constraining the potential beyond standard model new physics at high energy frontier. CEPC proposes a two year running period around the Z boson mass pole at high instataneous luminosity, providing a large data sample with $4\times 10^{12}$ $Z$ candidates generated in total. It allows a high precision measurement of $\sin^2θ^{\ell}_\text{eff}$ both in the lepton and quark final states, of which the uncertainty can be one order of magnitude lower than any previous measurement at the LEP, SLC, Tevatron and LHC. It will not only improve the overall precision of the $\sin^2θ^\ell_\text{eff}$ experimental determination to be comparable to the preicision of the theoretical calculation with two-loop radiative corrections, but also provide direct comparisons between different final states. In this paper, we also study the measurement of $\sin^2θ^{\ell}_\text{eff}$ at high mass region. With one month data taken, the precision of $\sin^2θ^{\ell}_\text{eff}$ measured at 130 GeV from $b$ quark final state is 0.00010, which will be an important experimental observation on the energy-running effect of $\sin^2θ^{\ell}_\text{eff}$.
