Measurement of the Properties of a Higgs Boson in the Four-Lepton Final State

The properties of a Higgs boson candidate are measured in the H→ZZ→4ℓ decay channel, with ℓ=e, μ, using data from pp collisions corresponding to an integrated luminosity of 5.1 fb−1 at the center-of-mass energy of s=7 TeV and 19.7 fb-1 at s=8 TeV, recorded with the CMS detector at the LHC. The new boson is observed as a narrow resonance with a local significance of 6.8 standard deviations, a measured mass of 125.6±0.4(stat)±0.2(syst) GeV, and a total width ≤3.4 GeV at the 95% confidence level. The production cross section of the new boson times its branching fraction to four leptons is measured to be 0.93-0.23+0.26(stat)-0.09+0.13(syst) times that predicted by the standard model. Its spin-parity properties are found to be consistent with the expectations for the standard-model Higgs boson. The hypotheses of a pseudoscalar and all tested spin-1 boson hypotheses are excluded at the 99% confidence level or higher. All tested spin-2 boson hypotheses are excluded at the 95% confidence level or higher.

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Muhammad Ahmad, Georgios Anagnostou, Konstantin Androsov, Giovanni Bianchi, Roberto Castello, Yixing Chen, Jie Chen, Tian Cheng, Giuseppe Codispoti, Alessandro Degano, Charles Dietz, Dipanwita Dutta, Matthias Finger, Francesco Fiori, Yu Fu, Yifei Guo, Ruchi Gupta, Csaba Hajdu, Alexis Kalogeropoulos, Donghyun Kim, Ji Hyun Kim, Ajay Kumar, Sanjeev Kumar, Vineet Kumar, Ekaterina Kuznetsova, Wei Li, Hao Liu, Shuai Liu, Werner Lustermann, Matteo Marone, 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, Qian Wang, Xiao Wang, Mingkui Wang, Jian Wang, Zheng Wang, Matthias Weber, Matthias Wolf, Wenjing Wu, Yong Yang, Fan Yang, Kai Yi, Lei Zhang, Yu Zheng
2014
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https://infoscience.epfl.ch/record/274815?ln=en

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Luminosity

Luminosity is an absolute measure of radiated electromagnetic power (light), the radiant power emitted by a light-emitting object over time. In astronomy, luminosity is the total amount of electromag

Standard Model

The Standard Model of particle physics is the theory describing three of the four known fundamental forces (electromagnetic, weak and strong interactions – excluding gravity) in the universe and cla

Confidence interval

In frequentist statistics, a confidence interval (CI) is a range of estimates for an unknown parameter. A confidence interval is computed at a designated confidence level; the 95% confidence level i