Search for a new resonance decaying to a Higgs boson and a scalar boson in events with two; ; b; ; jets and two; ; Z; ; bosons in proton-proton collisions at; ; ; s; ; =; 13; ; ; TeV; Journal Article
Overview
abstract
; A search is performed for a new resonance; ; X; ; decaying into a Higgs boson and a new scalar boson; ; Y; ; (; ; H; Y; ; ) including the case where; ; Y; ; is assumed to be a second Higgs boson (; ; H; H; ; ), using proton-proton collision data collected at; ; ; s; ; =; 13; ; ; TeV; ; , corresponding to an integrated luminosity of; ; 138; ; ; ; fb; ; −; 1; ; ; ; . This study performs a comprehensive exploitation of the; ; b; b; Z; Z; ; events, encompassing the following decay topologies. One; ; H; ; candidate is identified through its decay into a bottom quark-antiquark pair, while the other; ; H; ; or the; ; Y; ; candidate is selected through its decay into a pair of; ; Z; ; bosons. One; ; Z; ; boson is required to decay leptonically and the other, to decay into a pair of quarks or neutrinos. Events of interest are categorized based on the Lorentz boosts of the hadronically decaying; ; H; ; and; ; Z; ; bosons. Machine-learning-based discriminants, together with the reconstructed resonance mass, are employed across the different categories to separate signal from backgrounds, and their corresponding distributions are included in a simultaneous fit. No significant deviations from the standard model predictions are observed. Upper limits at the 95% confidence level are set on the; ; H; Y; ; and; ; H; H; ; production cross sections. For; ; H; Y; ; production, the upper limit on the cross section of the process; ; p; p; →; X; →; ; H; Y; ; →; b; b; Z; Z; ; ranges from 500 to 5 fb, with the most stringent constraints achieved for high-mass; ; X; ; resonances and; ; Y; ; masses near the threshold for decay into a pair of massive vector bosons. This is comparable to the sensitivity achieved in other analyses, which focus on; ; H; ; decays to; ; γ; γ; ; or; ; τ; τ; ; and; ; Y; ; decays into a pair of bottom quarks or massive vector bosons. For resonant; ; H; H; ; production, the upper limit on the cross section of; ; p; p; →; X; →; ; H; H; ; ; production is 1 pb for a high-mass resonance.;
