Search for heavy neutrinos or third-generation leptoquarks in final states with two hadronically decaying $\tau$ leptons and two jets in proton-proton collisions at $ \sqrt{s}=13 $ TeV

Khachatryan, Vardan; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Aşılar, Ece; Bergauer, Thomas; Brandstetter, Johannes; Brondolin, Erica; Dragicevic, Marko; Erö, Janos

doi:10.1007/JHEP03(2017)077

Search for heavy neutrinos or third-generation leptoquarks in final states with two hadronically decaying $\tau$ leptons and two jets in proton-proton collisions at $\sqrt{s}=13$ TeV

CMS

Collaboration

Dec 4, 2016

34 pages

Published in:

JHEP 03 (2017) 077

Published: Mar 14, 2017

e-Print:

1612.01190 [hep-ex]

DOI:

10.1007/JHEP03(2017)077

PDG: Mass Limits for Leptoquarks from Pair Production

Report number:

CMS-EXO-16-016,
CERN-EP-2016-286

Experiments:

CERN-LHC-CMS

View in:

reference search71 citations

Citations per year

Abstract: (Springer)

A search for new particles has been conducted using events with two high transverse momentum (p

_{T}

) τ leptons that decay hadronically, at least two high-p

_{T}

jets, and missing transverse energy from the τ lepton decays. The analysis is performed using data from proton-proton collisions, collected by the CMS experiment in 2015 at

\sqrt{s}=13

TeV, corresponding to an integrated luminosity of 2.1 fb

^{−1}

. The results are interpreted in two physics models. The first model involves heavy right-handed neutrinos, N

_{ℓ}

(ℓ = e, μ, τ), and right-handed charged bosons, W

_{R}

, arising in a left-right symmetric extension of the standard model. Masses of the W

_{R}

boson below 2.35 (1.63) TeV are excluded at 95% confidence level, assuming the N

_{τ}

mass is 0.8 (0.2) times the mass of the W

_{R}

boson and that only the N

_{τ}

flavor contributes to the W

_{R}

decay width. In the second model, pair production of third-generation scalar leptoquarks that decay into ττbb is considered. Third-generation scalar leptoquarks with masses below 740 GeV are excluded, assuming a 100% branching fraction for the leptoquark decay to a τ lepton and a bottom quark. This is the first search at hadron colliders for the third-generation Majorana neutrino, as well as the first search for third-generation leptoquarks in the final state with a pair of hadronically decaying τ leptons and jets.

Note:

Replaced with the published version. Added the journal reference and DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/EXO-16-016/index.html

Beyond Standard Model
Hadron-Hadron scattering (experiments)
protonproton scattering
p p: scattering
p p: colliding beams
W: right-handed
W: mass
mass: lower limit
leptoquark: pair production
leptoquark: scalar

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