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arXiv · 1812.10443

Search for contact interactions and large extra dimensions in the dilepton mass spectra from proton-proton collisions at $\sqrt{s} =$ 13 TeV

CMS Collaboration
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Abstract

A search for nonresonant excesses in the invariant mass spectra of electron and muon pairs is presented. The analysis is based on data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the CMS experiment in 2016, corresponding to a total integrated luminosity of 36 fb$^{-1}$. No significant deviation from the standard model is observed. Limits are set at 95% confidence level on energy scales for two general classes of nonresonant models. For a class of fermion contact interaction models, lower limits ranging from 20 to 32 TeV are set on the characteristic compositeness scale $Λ$. For the Arkani-Hamed, Dimopoulos, and Dvali model of large extra dimensions, the first results in the dilepton final state at 13 TeV are reported, and values of the ultraviolet cutoff parameter $Λ_\mathrm{T}$ below 6.9 TeV are excluded. A combination with recent CMS diphoton results improves this exclusion to $Λ_\mathrm{T}$ below 7.7 TeV, providing the most sensitive limits to date in nonhadronic final states.

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CMS Collaboration. 2019-04-22. Search for contact interactions and large extra dimensions in the dilepton mass spectra from proton-proton collisions at $\sqrt{s} =$ 13 TeV. https://doi.org/10.1007/jhep04(2019)114

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