Measurement of the charge asymmetry in top quark pair production in pp collisions at $\sqrt(s) =$ 8 TeV using a template method

The charge asymmetry in the production of top quark and antiquark pairs is measured in proton-proton collisions at a center-of-mass energy of 8 TeV. The data, corresponding to an integrated luminosity of 19.6 fb-1, were collected by the CMS experiment at the LHC. Events with a single isolated electron or muon, and four or more jets, at least one of which is likely to have originated from hadronization of a bottom quark, are selected. A template technique is used to measure the asymmetry in the distribution of differences in the top quark and antiquark absolute rapidities. The measured asymmetry is Acy=[0.33±0.26(stat)±0.33(syst)]%, which is the most precise result to date. The results are compared to calculations based on the standard model and on several beyond-the-standard-model scenarios.

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Muhammad Ahmad, Georgios Anagnostou, Konstantin Androsov, Alexandre Aubin, Roberto Castello, Juan Ramon Castiñeiras De Saa, Yixing Chen, Tian Cheng, Giuseppe Codispoti, Alessandro Degano, Charles Dietz, Milos Dordevic, Dipanwita Dutta, Matthias Finger, Francesco Fiori, Daniel Gonzalez, Ruchi Gupta, Csaba Hajdu, Peter Hansen, Alexis Kalogeropoulos, Viktor Khristenko, Ji Hyun Kim, Donghyun Kim, Ajay Kumar, Sanjeev Kumar, Vineet Kumar, Ekaterina Kuznetsova, Ho Ling Li, Wei Li, Hao Liu, Shuai Liu, Werner Lustermann, Bibhuprasad Mahakud, Matteo Marone, Thomas Muller, Ioannis Papadopoulos, Vladimir Petrov, Quentin Python, Andrea Rizzi, Paolo Ronchese, Sourav Sen, Ashish Sharma, Varun Sharma, Lesya Shchutska, Muhammad Shoaib, Michal Simon, Gurpreet Singh, Jan Steggemann, Wei Sun, Marco Trovato, Andromachi Tsirou, Paul Turner, Joao Varela, Rui Wang, Jian Wang, Qian Wang, Zheng Wang, Siyuan Wang, Matthias Weber, Matthias Wolf, Fan Xia, Meng Xiao, Zhirui Xu, Fan Yang, Yong Yang, Kai Yi, Hang Yin
2016
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https://infoscience.epfl.ch/record/274677?ln=fr

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