Combination of inclusive and differential $ \mathrm{t}\overline{\mathrm{t}} $ charge asymmetry measurements using ATLAS and CMS data at $ \sqrt{s}=7 $ and 8 TeV

This paper presents combinations of inclusive and differential measurements of the charge asymmetry (A $_{C}$ ) in top quark pair $\left(\mathrm{t}\overline{\mathrm{t}}\right)$ events with a lepton+jets signature by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. The data correspond to integrated luminosities of about 5 and 20 fb $^{−1}$ for each experiment, respectively. The resulting combined LHC measurements of the inclusive charge asymmetry are A $_{C}^{CHC7}$ = 0.005 ± 0.007 (stat) ± 0.006(syst) at 7 TeV and A $_{C}^{CHC8}$ = 0.0055 ± 0.0023 (stat) ± 0.0025 (syst) at 8 TeV. These values, as well as the combination of A $_{C}$ measurements as a function of the invariant mass of the $\mathrm{t}\overline{\mathrm{t}}$ system at 8 TeV, are consistent with the respective standard model predictions.

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https://infoscience.epfl.ch/record/274869?ln=fr

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Measurements of the Higgs boson production and decay rates and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp collision data at $ \sqrt{s}=7 $ and 8 TeV

Muhammad Ahmad, Benjamin William Allen, Georgios Anagnostou, Konstantin Androsov, Spyridon Argyropoulos, Alexandre Aubin, Nicolas Berger, Michele Bianco, Alexey Boldyrev, Simone Campana, João Carvalho, Roberto Castello, Juan Ramon Castiñeiras De Saa, Matevz Cerv, Susan Cheatham, Yixing Chen, Xin Chen, Chunhui Chen, Tian Cheng, Davide Cieri, Christophe Clément, Giuseppe Codispoti, Tommaso Colombo, Géraldine Conti, Greig Alan Cowan, Alessandro Degano, Sergey Denisov, Charles Dietz, Milos Dordevic, Dipanwita Dutta, Matthias Finger, Francesco Fiori, Julia Fischer, Daniel Gonzalez, Jun Guo, Yifei Guo, Ruchi Gupta, Seungkyu Ha, Csaba Hajdu, Peter Hansen, Ali Harb, James Henderson, Haoshuang Ji, Yi Jiang, Shan Jin, Alexis Kalogeropoulos, Viktor Khristenko, Donghyun Kim, Sun Hee Kim, Ji Hyun Kim, Vineet Kumar, Ajay Kumar, Sanjeev Kumar, Ekaterina Kuznetsova, Federica Legger, Ho Ling Li, Qi Li, Lei Li, Bing Li, Xuan Li, Yiming Li, Wei Li, Peter Lichard, Hao Liu, Bo Liu, Jian Liu, Kun Liu, Zhen Liu, Lulu Liu, Dong Liu, Shuai Liu, Werner Lustermann, Alexander Madsen, Bibhuprasad Mahakud, Andreas Alexander Maier, Gino Marceca, Ruslan Mashinistov, Lorenzo Massa, Maren Tabea Meinhard, Jean-Pierre Meyer, Thomas Muller, Snezana Nektarijevic, Marzio Nessi, Konstantinos Nikolopoulos, Preema Rennee Pais, Ioannis Papadopoulos, Vladimir Petrov, Quentin Python, Yang Qin, Robert Richter, Andrea Rizzi, Paolo Ronchese, Manfredi Ronzani, Eduardo Ros, Stefano Rosati, Edoardo Rossi, Daniela Salvatore, Sourav Sen, Ashish Sharma, Varun Sharma

Combined ATLAS and CMS measurements of the Higgs boson production and decay rates, as well as constraints on its couplings to vector bosons and fermions, are presented. The combination is based on the analysis of five production processes, namely gluon fusion, vector boson fusion, and associated production with a W or a Z boson or a pair of top quarks, and of the six decay modes H → ZZ, W W , γγ, ττ, bb, and μμ. All results are reported assuming a value of 125.09 GeV for the Higgs boson mass, the result of the combined measurement by the ATLAS and CMS experiments. The analysis uses the CERN LHC proton-proton collision data recorded by the ATLAS and CMS experiments in 2011 and 2012, corresponding to integrated luminosities per experiment of approximately 5 fb

^{−1}

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2016

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Precision electroweak measurements on the Z resonance☆☆☆

Georgios Anagnostou, Aurelio Bay, François Bianchi, Ivan Bozovic, Simone Campana, Francesco Cerutti, Peter Clarke, Greig Alan Cowan, Hans Dijkstra, Javier García Hernández, Csaba Hajdu, Peter Hansen, Shan Jin, Donghyun Kim, Ji Hyun Kim, Doohyun Kim, Zhen Liu, Werner Lustermann, Bénédicte Marie Maréchal, Peter Molnar, Raluca Anca Muresan, Niko Neufeld, Darren Robinson, Paolo Ronchese, Stefano Rosati, André Rouge, Eduardo Sanchez, Francisco Sanchez, Olivier Schneider, Sourav Sen, Varun Sharma, Pushpendra Singh, Michael Strauss, Liang Sun, Frédéric Teubert, Rémy Teuscher, Mark Tobin, Andromachi Tsirou, Horst Vogel, Qian Wang, Xiao Wang, Zheng Wang, Jian Wang, Matthias Weber, John Wilson, Songmei Wu, Zhirui Xu, Yong Yang, Igor Zacharov, Lei Zhang, Jian Zhao

We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLD experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, mZ Z, and ΓZ, its couplings to fermions, for example the ρ parameter and the efffective electroweak mixing angle for leptons, are precisely measured: mZ = 91.1875 ± 0.0021 GeV, ΓZ = 2.4952 ± 0.0023 GeV, ρℓ = 1.0050 ± 0.0010, sin2 θeff lept = 0.23153 ± 0.00016. The number of light neutrino species is determined to be 2.9840 ± 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, mt = 173-10 +13 GeV, and the mass of the W boson, mW = 80.363 ± 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of mt and mW, the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. © 2006 Elsevier B.V. All rights reserved.

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This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2658 new measurements from 644 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 112 reviews are many that are new or heavily revised including those on Heavy-Quark and Soft-Collinear Effective Theory, Neutrino Cross Section Measurements, Monte Carlo Event Generators, Lattice QCD, Heavy Quarkonium Spectroscopy, Top Quark, Dark Matter, V-cb & V-ub, Quantum Chromodynamics, High-Energy Collider Parameters, Astrophysical Constants, Cosmological Parameters, and Dark Matter. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov.

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