Search for CP violation in top quark-antiquark production and decay in proton-proton collisions

• Main Authors: Jui-Fa Tsai, 蔡瑞發
• Other Authors: Kai-Feng Chen
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/8z58pa

博士 === 國立臺灣大學 === 物理學研究所 === 105 === We present the first search for CP violation in top quark-antiquark pair events. The search is based on asymmetries in T-odd triple product correlation observables, where T is the time reversal operator. The analysis is based on a sample of proton-proton collisions at sqrt(s)=8TeV collected by the CMS experiment, corresponding to an integrated luminosity of 19.7fb^-1. The analysis is performed with events having exactly one electron or muon and at least four jets. The T-odd observables are measured using the linearly independent four-momentum vectors associated with top quark production and decay. The measured asymmetries exhibit no evidence for CP-violating effects, in agreement with the standard model prediction.