CMSPASHIG24001  
Search for HHWW couplings in the VBS production of $ \mathrm{W^{\pm}W^{\pm}H} $, with $ \mathrm{H\rightarrow b\bar{b}} $ decays  
CMS Collaboration  
27 July 2024  
Abstract: A search is performed for anomalous HHWW couplings based on the process $ \mathrm{pp\rightarrow W^{\pm}W^{\pm}H+jj} $, using protonproton collision data collected by the CMS experiment at a centerofmass energy of $ \sqrt{s}= $ 13 TeV in the LHC Run 2, corresponding to a total integrated luminosity of 138 fb$ ^{1} $. The search is performed in final states that contain a forwardbackward jet pair, two W bosons that decay to samesign leptons, and a Higgs boson that decays into two bottom quarks. Boosted decision trees are trained to separate the signal from the background. The HHWW coupling modifier $ \kappa_{WW} $ is constrained at 95% confidence level to be in the interval $[3.3, 5.3]$, consistent with the expected interval of $[2.4, 4.4]$.  
Links: CDS record (PDF) ; CADI line (restricted) ; 
Figures  
png pdf 
Figure 1:
Treelevel Feynman diagrams of vector boson scattering multiboson productions with Higgs boson in the final state, with (a) related to the Higgs selfcoupling ($ {\kappa_\lambda} $), and (b) related to the Higgs gauge quartic coupling ($ {\kappa_{VV}} $). 
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Figure 1a:
Treelevel Feynman diagrams of vector boson scattering multiboson productions with Higgs boson in the final state, with (a) related to the Higgs selfcoupling ($ {\kappa_\lambda} $), and (b) related to the Higgs gauge quartic coupling ($ {\kappa_{VV}} $). 
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Figure 1b:
Treelevel Feynman diagrams of vector boson scattering multiboson productions with Higgs boson in the final state, with (a) related to the Higgs selfcoupling ($ {\kappa_\lambda} $), and (b) related to the Higgs gauge quartic coupling ($ {\kappa_{VV}} $). 
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Figure 2:
DataMC comparison of $ m_{jj} $ and $ \Delta\eta_{jj} $ distributions in the preselection regions. Two signal hypotheses, with one for $ {\kappa_{VV}} = $ 1 which represents the SM and the other for $ {\kappa_{VV}} = $ 4.5, are plotted. The uncertainty band in the ratio plots represents the prefit statistical uncertainty of the Monte Carlo, which corresponds to the uncertainty band in the distribution plots. 
png pdf 
Figure 2a:
DataMC comparison of $ m_{jj} $ and $ \Delta\eta_{jj} $ distributions in the preselection regions. Two signal hypotheses, with one for $ {\kappa_{VV}} = $ 1 which represents the SM and the other for $ {\kappa_{VV}} = $ 4.5, are plotted. The uncertainty band in the ratio plots represents the prefit statistical uncertainty of the Monte Carlo, which corresponds to the uncertainty band in the distribution plots. 
png pdf 
Figure 2b:
DataMC comparison of $ m_{jj} $ and $ \Delta\eta_{jj} $ distributions in the preselection regions. Two signal hypotheses, with one for $ {\kappa_{VV}} = $ 1 which represents the SM and the other for $ {\kappa_{VV}} = $ 4.5, are plotted. The uncertainty band in the ratio plots represents the prefit statistical uncertainty of the Monte Carlo, which corresponds to the uncertainty band in the distribution plots. 
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Figure 3:
Postfit shapes for the SR, including (a) $ \ell\ell $ final state (b) $ \ell\tau $ final state. The uncertainty band in the ratio plots represents the postfit uncertainty of the Monte Carlo, which corresponds to the uncertainty band in the distribution plots. 
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Figure 3a:
Postfit shapes for the SR, including (a) $ \ell\ell $ final state (b) $ \ell\tau $ final state. The uncertainty band in the ratio plots represents the postfit uncertainty of the Monte Carlo, which corresponds to the uncertainty band in the distribution plots. 
png pdf 
Figure 3b:
Postfit shapes for the SR, including (a) $ \ell\ell $ final state (b) $ \ell\tau $ final state. The uncertainty band in the ratio plots represents the postfit uncertainty of the Monte Carlo, which corresponds to the uncertainty band in the distribution plots. 
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Figure 4:
Limits of $ \kappa_{VV} $ with CL=95%. 
Tables  
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Table 1:
Input variables used for the event kinematics BDT. 
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Table 2:
The postfit yields of the CR, for $ \ell\ell $ and $ \ell\tau $ categories separately. The errors for total background include the statistical and systematic uncertainties. 
Summary 
Data recorded with the CMS experiment during LHC Run 2 amounting to 138 $ \mathrm{fb}^{1} $ of pp collisions at $ \sqrt{s}= $ 13 TeV are used to search for anomalous couplings in the process $ \mathrm{pp} \rightarrow \mathrm{W}^{ \pm} \mathrm{W}^{ \pm} \mathrm{H}+\mathrm{jj} $, where the Higgs boson decays to two bottom quarks and the W bosons decay leptonically. The analysis focuses on the channel in which the two bjets are merged. The observed(expected) 95% CL interval for $ \kappa_{WW} $ is $[3.3, 5.3]$($[2.4, 4.4]$). This marks the first analysis of the $ \mathrm{pp} \rightarrow \mathrm{W}^{ \pm} \mathrm{W}^{ \pm} \mathrm{H}+\mathrm{jj} $ process and opens the possibility of further analysis of the same process with different final states. 
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