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Publication# Combinations of single-top-quark production cross-section measurements and |f$_{LV}$V$_{tb}$| determinations at $ \sqrt{s} $ = 7 and 8 TeV with the ATLAS and CMS experiments

Muhammad Ahmad, Benjamin William Allen, Cherifa Sabrina Amrouche, Georgios Anagnostou, Konstantin Androsov, Spyridon Argyropoulos, Tagir Aushev, Mathieu Benoit, Thomas Berger, Nicolas Berger, Michele Bianco, Alexey Boldyrev, Lucrezia Stella Bruni, Simone Campana, Xin Chen, Jie Chen, Cheng Chen, Yixing Chen, Chunhui Chen, Tian Cheng, Davide Cieri, Christophe Clément, Giuseppe Codispoti, Greig Alan Cowan, Pratyush Das, Abhisek Datta, Sergey Denisov, Milos Dordevic, Dipanwita Dutta, Matthias Finger, Francesco Fiori, Daniel Gonzalez, Jun Guo, Yifei Guo, Ruchi Gupta, Seungkyu Ha, Csaba Hajdu, Peter Hansen, Ali Harb, Miao Hu, Haoshuang Ji, Yi Jiang, Shan Jin, Alexis Kalogeropoulos, Sana Ketabchi Haghighat, Viktor Khristenko, Donghyun Kim, Ji Hyun Kim, Sanjeev Kumar, Ajay Kumar, Vineet Kumar, Ekaterina Kuznetsova, Marie Christine Lanfermann, Robert Johannes Langenberg, Federica Legger, Niklaus Lehmann, Bing Li, Lei Li, Ho Ling Li, Wei Li, Yiming Li, Qi Li, Jing Li, Ke Li, Xuan Li, Fan Li, Kun Liu, Yang Liu, Zhen Liu, Bo Liu, Hao Liu, Jian Liu, Werner Lustermann, Bibhuprasad Mahakud, Gino Marceca, Ruslan Mashinistov, Lara Hannan Mason, Lorenzo Massa, Maren Tabea Meinhard, Jean-Pierre Meyer, Amr Mohamed, Thomas Muller, Snezana Nektarijevic, Marzio Nessi, Konstantinos Nikolopoulos, Ioannis Papadopoulos, Vladimir Petrov, Quentin Python, Yang Qin, Robert Richter, Andrea Rizzi, Paolo Ronchese, Manfredi Ronzani, Stefano Rosati, Edoardo Rossi, Daniela Salvatore, Enrico Junior Schioppa, Sourav Sen, Abhishek Sharma, Ashish Sharma

*Springer, *2019

Journal paper

Journal paper

Abstract

This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at $\sqrt{s}$ = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb$^{−1}$ at $\sqrt{s}$ = 7 TeV and 12.2 to 20.3 fb$^{−1}$ at $\sqrt{s}$ = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 ± 5.7 pb and 87.7 ± 5.8 pb at $\sqrt{s}$ = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 ± 4.1 pb and 23.1 ± 3.6 pb at $\sqrt{s}$ = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 ± 1.4 pb at $\sqrt{s}$ = 8 TeV. The square of the magnitude of the CKM matrix element V$_{tb}$ multiplied by a form factor f$_{LV}$ is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V$_{td}$|, |V$_{ts}$| ≪ |V$_{tb}$|. All the |f$_{LV}$V$_{tb}$|$^{2}$ determinations, extracted from individual ratios at $\sqrt{s}$ = 7 and 8 TeV, are combined, resulting in |f$_{LV}$V$_{tb}$| = 1.02 ± 0.04 (meas.) ± 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.

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2019