Abstract
A search for a heavy neutral Higgs boson, A, decaying into a Z boson and another heavy Higgs boson, H, is performed using a data sample corresponding to an integrated luminosity of 139 fb^{-1} from proton–proton collisions at sqrt{s} = 13 text {TeV} recorded by the ATLAS detector at the LHC. The search considers the Z boson decaying into electrons or muons and the H boson into a pair of b-quarks or W bosons. The mass range considered is 230–800 text {GeV} for the A boson and 130–700 text {GeV} for the H boson. The data are in good agreement with the background predicted by the Standard Model, and therefore 95% confidence-level upper limits for sigma times B(Arightarrow ZH)times B(Hrightarrow bb ; text {or} ; H rightarrow WW) are set. The upper limits are in the range 0.0062–0.380 pb for the Hrightarrow bb channel and in the range 0.023–8.9 pb for the Hrightarrow WW channel. An interpretation of the results in the context of two-Higgs-doublet models is also given.
Highlights
The addition of a second Higgs doublet leads to five Higgs bosons after electroweak symmetry breaking
This heavy Higgs boson decay is dominant in parts of the 2HDM parameter space close to, but not exactly at, the weak decoupling limit [41] and it provides a new way to look for W W resonances in a final state that has been less explored by other LHC searches
Data recorded by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 139 fb−1 from proton–proton collisions at a centre-of-mass energy 13 TeV, are used to search for a heavy Higgs boson, A, decaying into Z H, where H denotes another heavy Higgs boson with mass m H > 125 GeV
Summary
The addition of a second Higgs doublet leads to five Higgs bosons after electroweak symmetry breaking. The H → W W decay channel is considered in the case where both W bosons decay hadronically This heavy Higgs boson decay is dominant in parts of the 2HDM parameter space close to, but not exactly at, the weak decoupling limit [41] and it provides a new way to look for W W resonances in a final state that has been less explored by other LHC searches. Both final states considered allow full reconstruction of the A boson’s decay kinematics.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
