Measurement of the mass difference between top quark and antiquark in pp collisions at $\sqrt{s} = 8$ TeV

The invariance of the standard model (SM) under the CPT transformation predicts equality of particle and antiparticle masses. This prediction is tested by measuring the mass difference between the top quark and antiquark ( Δmt=mt−mt‾ ) that are produced in pp collisions at a center-of-mass energy of 8 TeV, using events with a muon or an electron and at least four jets in the final state. The analysis is based on data corresponding to an integrated luminosity of 19.6 fb−1 collected by the CMS experiment at the LHC, and yields a value of Δmt=−0.15±0.19(stat)±0.09(syst) GeV , which is consistent with the SM expectation. This result is significantly more precise than previously reported measurements.

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Muhammad Ahmad, Georgios Anagnostou, Konstantin Androsov, Giovanni Bianchi, Roberto Castello, Jie Chen, Yixing Chen, Tian Cheng, Giuseppe Codispoti, Alessandro Degano, Charles Dietz, Milos Dordevic, Dipanwita Dutta, Matthias Finger, Francesco Fiori, Yu Fu, Yifei Guo, Ruchi Gupta, Csaba Hajdu, Alexis Kalogeropoulos, Ji Hyun Kim, Donghyun Kim, Vineet Kumar, Ajay Kumar, Sanjeev Kumar, Ekaterina Kuznetsova, Wei Li, Shuai Liu, Hao Liu, Werner Lustermann, Matteo Marone, Amr Mohamed, Thomas Muller, Ioannis Papadopoulos, Vladimir Petrov, Andrea Rizzi, Paolo Ronchese, Sourav Sen, Varun Sharma, Ashish Sharma, Lesya Shchutska, Muhammad Shoaib, Michal Simon, Gurpreet Singh, Jan Steggemann, Wei Sun, Andromachi Tsirou, Paul Turner, Joao Varela, Jian Wang, Qian Wang, Xiao Wang, Mingkui Wang, Zheng Wang, Matthias Weber, Matthias Wolf, Wenjing Wu, Yong Yang, Fan Yang, Kai Yi, Lei Zhang, Yu Zheng
Elsevier, 2017
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https://infoscience.epfl.ch/record/274971?ln=fr

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