标题： Z玻色子衰变的左手-右手电荷不对称性的首次测量及sin^2(θ_eff)的新确定 显示英文标题

标题： First Measurement of the Left-Right Charge Asymmetry in Hadronic Z Boson Decays and a New Determination of sin^2(theta_eff)

摘要： 我们给出了在强子Z玻色子衰变中电荷左-右不对称性 A_Q^{观察}的首个测量结果。该测量是在 E_cm = 91.27 GeV 条件下，利用SLC斯坦福直线对撞机上的极化电子束完成的。通过对89838个事例的分析，我们得到 A_Q^{观察}= 0.225 ± 0.056 ± 0.019，由此得出电子左-右不对称参数 A_e = 0.162 ± 0.041 ± 0.014，以及 sin^2(θ_eff) = 0.2297 ± 0.0052 ± 0.0018。此外，A_Q^{观察}的测量与横截面左-右不对称性的结合能够独立于电子束极化的值来确定 A_e。 显示英文摘要

摘要： We present the first measurement of the left-right charge asymmetry A_Q^{obs} in hadronic Z boson decays. This was performed at E_cm = 91.27 GeV with the SLD at the SLAC Linear Collider with a polarized electron beam. Using 89838 events, we obtain A_Q^{obs}=0.225+-0.056+-0.019 which leads to a measurement of the electron left-right asymmetry parameter, A_e=0.162+-0.041+-0.014, and sin^2(theta_eff)=0.2297+-0.0052 +-0.0018. Also, the A_Q^{obs} measurement combined with the left-right cross section asymmetry determines A_e independently of the value of the electron-beam polarization.