Speaker
Description
This study presents a search for a vector boson $V$ ($W$ or $Z$ boson) associated Higgs boson pair ($HH$) production process using proton-proton ($pp$) collision data at a center-of-mass energy of 13 TeV, collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb$^{-1}$. The processes include $pp \rightarrow ZHH$ and $pp \rightarrow WHH$ production, considering all hadronic and leptonic decays of $V$ bosons involving electrons, muons, and neutrinos. The search focuses on the $b\bar{b}b\bar{b}$ decay channel of pairs of Higgs bosons. In our study, we set the upper limits for the $VHH$ production cross section at a 95\% confidence level. The observed (and expected) limits were found to be 294 (and 124) times the predictions of the standard model, respectively. Additionally, we conducted an evaluation of the modifiers of the Higgs boson trilinear self-coupling, denoted as $\kappa_\lambda$, and the coupling between two Higgs bosons and two vector bosons, represented by $\kappa_{2V}$. The confidence intervals at 95\% for $\kappa_\lambda$ were observed (expected) to be between $-37.7$ and $37.2$ ($-30.1$ and $28.9$), and for $\kappa_{2V}$, between $-12.2$ and $13.5$ ($-7.2$ and $8.9$), indicating the constraints placed on these parameters by our analysis.
