Measurement of Four-Jet Production in Proton-Proton Collisions at $\sqrt{s}=7$ TeV

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
Article

Résumé

Measurements of the differential cross sections for the production of exactly four jets in proton-proton collisions are presented as a function of the transverse momentum pT and pseudorapidity η, together with the correlations in azimuthal angle and the pT balance among the jets. The data sample was collected in 2010 at a center-of-mass energy of 7 TeV with the CMS detector at the LHC, with an integrated luminosity of 36 pb−1. The cross section for exactly four jets, with two hard jets of pT>50 GeV each, together with two jets of pT>20 GeV each, within |η|<4.7 is measured to be σ=330±5(stat.)±45(syst.) nb. It is found that fixed-order matrix element calculations including parton showers describe the measured differential cross sections in some regions of phase space only, and that adding contributions from double parton scattering brings the Monte Carlo predictions closer to the data.

Official source

https://infoscience.epfl.ch/record/274812?ln=fr

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