Search for Z' bosons decaying to pairs of heavy Majorana neutrinos in proton-proton collisions at $\sqrt{s}$ = 13 TeV

Abstract

A search for the production of pairs of heavy Majorana neutrinos (N${}_{\ell }$) from the decays of Z' bosons is performed using the CMS detector at the LHC. The data were collected in proton-proton collisions at a center-of-mass energy of $\sqrt{s}$ = 13 TeV, with an integrated luminosity of 138 fb${}^{-1}$. The signature for the search is an excess in the invariant mass distribution of the final-state objects, two same-flavor leptons (e or $\mu$) and at least two jets. No significant excess of events beyond the expected background is observed. Upper limits at 95% confidence level are set on the product of the Z' production cross section and its branching fraction to a pair of N${}_{\ell }$, as functions of N${}_{\ell }$ and Z' boson masses ($m_{{\mathrm{N}}_{\ell }}$ and $m_{{\mathrm{Z}}^{\prime }}$, respectively) for $m_{{\mathrm{Z}}^{\prime }}$ from 0.4 to 4.6 TeV and $m_{{\mathrm{N}}_{\ell }}$ from 0.1 TeV to $m_{{\mathrm{Z}}^{\prime }}$/2. In the theoretical framework of a left-right symmetric model, exclusion bounds in the $m_{{\mathrm{N}}_{\ell }}-m_{{\mathrm{Z}}^{\prime }}$ plane are presented in both the electron and muon channels. The observed upper limit on $m_{{\mathrm{Z}}^{\prime }}$ reaches up to 4.42 TeV. These are the most restrictive limits to date on the mass of N${}_{\ell }$ as a function of the Z' boson mass.

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/EXO-20-006 (CMS Public Pages)

References in corpus (8)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• An Introduction to PYTHIA 8.2
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• Comparative study of various algorithms for the merging of parton showers and matrix elements in hadronic collisions
• Jet substructure as a new Higgs search channel at the LHC
• Single-top Wt-channel production matched with parton showers using the POWHEG method
• Pileup Per Particle Identification
• On the most constraining cosmological neutrino mass bounds

Cited by in corpus (2)

• Review of searches for vector-like quarks, vector-like leptons, and heavy neutral leptons in proton-proton collisions at $\sqrt{s}$ = 13 TeV at the CMS experiment
• Bubble wall velocity and gravitational wave in the minimal left-right symmetric model