Springer : High-precision limits on $W–W'$ and $Z–Z'$ mixing from diboson production using the full LHC Run 2 ATLAS data set

Pankov, A.A.; Osland, P.; Bednyakov, V.A.; Serenkova, I.A.

doi:10.1140/epjc/s10052-020-8075-7

Article
Report number	arXiv:1912.02106
Title	High-precision limits on $W–W'$ and $Z–Z'$ mixing from diboson production using the full LHC Run 2 ATLAS data set
Author(s)	Pankov, A.A. (Gomel State Tech. U., ICTP ; Minsk, Inst. Nucl. Problems ; Dubna, JINR) ; Osland, P. (Bergen U.) ; Serenkova, I.A. (Gomel State Tech. U., ICTP) ; Bednyakov, V.A. (Dubna, JINR)
Publication	2020-06-05
Imprint	2019-12-03
Number of pages	20
Note	20 pages, 6 figures. arXiv admin note: substantial text overlap with arXiv:1904.01432, arXiv:1809.08933. v2: clarifications, version published in EPJC
In:	Eur. Phys. J. C 80 (2020) 503
DOI	10.1140/epjc/s10052-020-8075-7
Subject category	hep-ex ; Particle Physics - Experiment ; hep-ph ; Particle Physics - Phenomenology
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Abstract	The full ATLAS Run 2 data set with time-integrated luminosity of 139 fb$^{-1}$ in the diboson channels in hadronic final states is used to probe a simple model with an extended gauge sector (EGM), proposed by Altarelli et al., and often taken as a convenient benchmark by experimentalists. This model accommodates new charged $W'$ and neutral $Z'$ vector bosons with modified trilinear Standard Model gauge couplings, decaying into electroweak gauge boson pairs $WZ$ or $WW$, where $W$/$Z$ decay hadronically. Exclusion limits at the 95% C.L. on the $Z'$ and $W'$ resonance production cross section times branching ratio to electroweak gauge boson pairs in the mass range of $\sim$ 1 - 5 TeV are here converted to constraints on $W$-$W'$ and $Z$-$Z'$ mixing parameters and masses for the EGM. We present exclusion regions on the parameter space of the $W'$ and $Z'$ by using the full Run 2 data set comprised of $pp$ collisions at $\sqrt{s}=13$ TeV and recorded by the ATLAS detector at the CERN LHC. The obtained exclusion regions are significantly extended compared to those obtained from the previous analysis performed with Tevatron data as well as with LHC data collected at 7 and 8 TeV in Run 1 and are the most stringent bounds to date.
Copyright/License	publication: © 2020-2025 The Author(s) (License: CC-BY-4.0) preprint: (License: arXiv nonexclusive-distrib 1.0)

$Branching fraction $\text{BR}(W'\to WZ)$ (solid) vs $M_{W'}$ in the EGM for $W$-$W'$ mixing factor $\xi_{W\text{-}W^\prime}=3\cdot 10^{-4}$, $10^{-3}$ and $10^{-2}$. The shaded bands represent the uncertainty resulting from the inclusion of the $WH$ decay mode, the upper and lower bounds correspond to the assumptions $\Gamma_{W'}^{WH}=0$ and $\Gamma_{W'}^{WH}=\Gamma_{W'}^{WZ}$, respectively.$ $Branching fraction $\text{BR}(Z'\to W^+W^-)$ vs.\ $M_{Z'}$ in the EGM for non-zero $Z$-$Z'$ mixing factor $\xi_{Z\text{-}Z^\prime}=2\cdot 10^{-3}$, $1\cdot 10^{-3}$ and $5\cdot 10^{-4}$. The shaded bands represent the uncertainty resulting from the inclusion of the $ZH$ decay mode to the total decay width $\Gamma_{Z'}$, the upper and lower bounds correspond to the assumptions $\Gamma_{Z'}^{ZH}=0$ and $\Gamma_{Z'}^{ZH}=\Gamma_{Z'}^{W^+W^-}$, respectively.$ $Observed $95\%$ C.L. upper limits on the production cross section times the branching fraction, $\sigma_{95\%}\times \text{BR}(W'\to WZ)$, as a function of the $W'$ mass, $M_{W'}$, showing ATLAS data on the fully hadronic final states for $36.7~\text{fb}^{-1}$ \cite{Aaboud:2017eta} and $139~\text{fb}^{-1}$ \cite{Aad:2019fbh}. The theoretical production cross sections $\sigma(pp\to W'+X)\times \text{BR}(W'\to WZ)$ for the ${\rm EGM}$ are calculated from PYTHIA with a $W'$ boson mass-dependent $K$-factor used to correct for NNLO QCD effects, and given by solid curves, for mixing factor $\xi_{W\text{-}W^\prime}$ ranging from $10^{-2}$ and down to $3\cdot 10^{-4}$. The shaded bands are defined like in Fig.~\ref{BR-wprime}. The area lying below the long-dashed curve labelled NWA corresponds to the region where the narrow-resonance assumption is satisfied. The lower boundary of the region excluded by the unitarity violation arguments is indicated by the dot-dashed curve \cite{Alves:2009aa, Serenkova:2019zav}.$ Show more plots

Corresponding record in: Inspire

Back to search

Record created 2019-12-21, last modified 2021-11-13

Similar records

Article from SCOAP3:
scoap3-fulltext -