CMS-PAS-SMP-13-008 | ||

Search for anomalous couplings in the production of WW and WZ pairs decaying semileptonically in proton-proton collisions at $\sqrt{s}= $ 8 TeV | ||

CMS Collaboration | ||

December 2016 | ||

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Abstract:
A search for new physics is reported, in which the new physics appears in anomalous couplings of triple gauge boson vertices involving WW or WZ diboson production from proton-proton collisions. The search is performed on a sample of events containing a W boson that decays leptonically and a W or Z boson where the decay products are merged into a single jet. The data sample, collected at $\sqrt{s} = $ 8 TeV with the CMS detector at the LHC, corresponds to an integrated luminosity of 19 fb$^{-1}$. No evidence for anomalous triple gauge couplings is found and the following 95% confidence limits are set on their magnitudes: $\lambda$($ [-0.011, 0.011]$), $\Delta{\kappa_\gamma}$($ [-0.044, 0.063]$), and $\Delta{G_1^Z}$($ [-0.0087, 0.024]$). These limits are also translated into their effective field theory equivalents: $c_{WWW}/\Lambda^2$($ [-2.7, 2.7] \mathrm{TeV}^{-2}$), $c_B/\Lambda^2$($ [-14, 17] \mathrm{TeV}^{-2}$), and $c_W/\Lambda^2$($ [-2.0, 5.7] \mathrm{TeV}^{-2}$).
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Links:
CDS record (PDF) ;
inSPIRE record ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, PLB 772 (2017) 21.The superseded preliminary plots can be found here. |

Figures | |

png pdf |
Figure 1:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png |
Figure 1-a:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png |
Figure 1-b:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png |
Figure 1-c:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png |
Figure 1-d:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png |
Figure 1-e:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png |
Figure 1-f:
Distributions of the merged jet invariant mass for muons, (top) and electrons (bottom) with the projections of the relevant components overlaid. The merged jet invariant mass is plotted for all events (left), after subtraction of all components except the diboson (center) and subsequent normalized residual or pull distributions: $(\text {data} - \text {fit})/(\text {fituncertainty})$ (right). The error bars represent statistical uncertainties. The dashed vertical lines mark the signal region of $70 |

png pdf |
Figure 2:
V$_{had}$ $ {p_{\mathrm {T}}} $ distributions for the muon (left) and electron (right) merged jet channels after full selection and with the requirement $70 GeV < m_{J} < 100 GeV $. The MC errors are purely statistical. The stacked histogram shapes are taken from simulation. They are normalized according to the fit to the observed spectrum in data, with the exception of the SM WV, which is normalized to the theoretical prediction. Below we show the data/MC ratio. The last bin includes the overflow. |

png |
Figure 2-a:
V$_{had}$ $ {p_{\mathrm {T}}} $ distributions for the muon (left) and electron (right) merged jet channels after full selection and with the requirement $70 GeV < m_{J} < 100 GeV $. The MC errors are purely statistical. The stacked histogram shapes are taken from simulation. They are normalized according to the fit to the observed spectrum in data, with the exception of the SM WV, which is normalized to the theoretical prediction. Below we show the data/MC ratio. The last bin includes the overflow. |

png |
Figure 2-b:
V$_{had}$ $ {p_{\mathrm {T}}} $ distributions for the muon (left) and electron (right) merged jet channels after full selection and with the requirement $70 GeV < m_{J} < 100 GeV $. The MC errors are purely statistical. The stacked histogram shapes are taken from simulation. They are normalized according to the fit to the observed spectrum in data, with the exception of the SM WV, which is normalized to the theoretical prediction. Below we show the data/MC ratio. The last bin includes the overflow. |

png pdf |
Figure 3-a:
Above are depicted the 68% and 95% CL observed and expected exclusion contours for three pairwise combinations of the anomalous triple gauge coupling parameters in the HISZ parametrization (top) and in the effective field theory formulation (bottom). |

png pdf |
Figure 3-b:
Above are depicted the 68% and 95% CL observed and expected exclusion contours for three pairwise combinations of the anomalous triple gauge coupling parameters in the HISZ parametrization (top) and in the effective field theory formulation (bottom). |

png pdf |
Figure 3-c:
Above are depicted the 68% and 95% CL observed and expected exclusion contours for three pairwise combinations of the anomalous triple gauge coupling parameters in the HISZ parametrization (top) and in the effective field theory formulation (bottom). |

png pdf |
Figure 3-d:
Above are depicted the 68% and 95% CL observed and expected exclusion contours for three pairwise combinations of the anomalous triple gauge coupling parameters in the HISZ parametrization (top) and in the effective field theory formulation (bottom). |

png pdf |
Figure 3-e:
Above are depicted the 68% and 95% CL observed and expected exclusion contours for three pairwise combinations of the anomalous triple gauge coupling parameters in the HISZ parametrization (top) and in the effective field theory formulation (bottom). |

png pdf |
Figure 3-f:
Above are depicted the 68% and 95% CL observed and expected exclusion contours for three pairwise combinations of the anomalous triple gauge coupling parameters in the HISZ parametrization (top) and in the effective field theory formulation (bottom). |

Tables | |

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Table 1:
Observed and expected event yields and associated fractions (in parentheses) with respect to the prefit values extracted in the signal region ($70 |

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Table 2:
Summary of one-dimensional limits placed on each coupling parameter. Each number pair represents the observed 95% confidence interval for that parameter. |

Summary |

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Compact Muon Solenoid LHC, CERN |