A search for new particles has been conducted using events with two high transverse momentum τ leptons that decay hadronically and at least two energetic jets. The analysis is performed using data from proton-proton collisions at s=13 TeV, collected by the CMS experiment at the LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb−1 . The observed data are consistent with standard model expectations. The results are interpreted in the context of two physics models. The first model involves right-handed charged bosons, W_R , that decay to heavy right-handed Majorana neutrinos, N_ℓ (ℓ = e, μ, τ), arising in a left-right symmetric extension of the standard model. The model considers that N_e and N_μ are too heavy to be detected at the LHC. Assuming that the N_τ mass is half of the W_R mass, masses of the W_R boson below 3.50 TeV are excluded at 95% confidence level. Exclusion limits are also presented considering different scenarios for the mass ratio between N_τ and W_R , as a function of W_R mass. In the second model, pair production of third-generation scalar leptoquarks that decay into ττbb is considered, resulting in an observed exclusion region with leptoquark masses below 1.02 TeV, assuming a 100% branching fraction for the leptoquark decay to a τ lepton and a bottom quark. These results represent the most stringent limits to date on these models.

Search for heavy neutrinos and third-generation leptoquarks in hadronic states of two τ leptons and two jets in proton-proton collisions at √s=13 TeV

Ravera F.;Meridiani P.;Amapane N.;Argiro S.;Bellan R.;Costa M.;Covarelli R.;Kiani B.;Migliore E.;Monaco V.;Monteil E.;Obertino M. M.;Pacher L.;Pinna Angioni G. L.;Romero A.;Sacchi R.;Sola V.;Solano A.;Rumerio P.;
2019-01-01

Abstract

A search for new particles has been conducted using events with two high transverse momentum τ leptons that decay hadronically and at least two energetic jets. The analysis is performed using data from proton-proton collisions at s=13 TeV, collected by the CMS experiment at the LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb−1 . The observed data are consistent with standard model expectations. The results are interpreted in the context of two physics models. The first model involves right-handed charged bosons, W_R , that decay to heavy right-handed Majorana neutrinos, N_ℓ (ℓ = e, μ, τ), arising in a left-right symmetric extension of the standard model. The model considers that N_e and N_μ are too heavy to be detected at the LHC. Assuming that the N_τ mass is half of the W_R mass, masses of the W_R boson below 3.50 TeV are excluded at 95% confidence level. Exclusion limits are also presented considering different scenarios for the mass ratio between N_τ and W_R , as a function of W_R mass. In the second model, pair production of third-generation scalar leptoquarks that decay into ττbb is considered, resulting in an observed exclusion region with leptoquark masses below 1.02 TeV, assuming a 100% branching fraction for the leptoquark decay to a τ lepton and a bottom quark. These results represent the most stringent limits to date on these models.
2019
2019
3
1
41
Beyond Standard Model; Dark matter; Hadron-Hadron scattering (experiments)
Sirunyan A.M.; Tumasyan A.; Adam W.; Ambrogi F.; Asilar E.; Bergauer T.; Brandstetter J.; Dragicevic M.; Ero J.; Escalante Del Valle A.; Flechl M.; Fr...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1738385
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