Measurement of the effective weak mixing angle at the CEPC  

作　　者：赵振宇 杨思奇 阮曼奇 刘明辉 韩良 Zhenyu Zhao;Siqi Yang;Manqi Ruan;Minghui Liu;Liang Han(Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China;Institution of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,Chin)

机构地区：[1]Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China [2]Institution of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Physics C》2023年第12期10-15,共6页中国物理C（英文版）

基　　金：the"USTC Research Funds of the Double First-Class Initiative",the International Partnership Program of Chinese Academy of Sciences(113111KYSB20190030);the Innovative Scientific Program of Institute of High Energy Physics。

摘　　要：We present a study of the measurement of the effective weak mixing angle parameter(sin^(2)θ^(l)_(eff))at the Circular Electron Positron Collider(CEPC).As a fundamental physics parameter,sin^(2)θ_(eff)^(l) 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 the 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 × 10^(12)Z candidates generated in total.It allows a high precision measurement of sin^(2)θ^(l)_(eff) both in the lepton and quark final states,where the uncertainty can be one order of magnitude lower than any previous measurement at the LEP,SLC,Tevatron,and LHC.It will improve the overall precision of the sin^(2)θ^(l)_(eff) experimental determination to be comparable to the preicision of the theoretical calculation with two-loop radiative corrections,and it will also provide direct comparisons between different final states.In this paper,we also study the measurement of sin^(2)θ^(l)_(eff) in the high mass region.Taking data for one month,the precision of sin^(2)θ^(l)_(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^(2)θ^(l)_(eff).

关 键 词：effective weak mixing angle Circular Electron Positron Collider(CEPC) ELECTROWEAK 

分 类 号：O572.214[理学—粒子物理与原子核物理]