Nonresonant Higgs Boson Research Articles

Search for Nonresonant Pair Production of Highly Energetic Higgs Bosons Decaying to Bottom Quarks.

A search for nonresonant Higgs boson (H) pair production via gluon and vector boson (V) fusion is performed in the four-bottom-quark final state, using proton-proton collision data at 13TeV corresponding to 138 fb^{-1} collected by the CMS experiment at the LHC. The analysis targets Lorentz-boosted H pairs identified using a graph neural network. It constrains the strengths relative to the standard model of the H self-coupling and the quartic VVHH couplings, κ_{2V}, excluding κ_{2V}=0 for the first time, with a significance of 6.3 standard deviations when other H couplings are fixed to their standard model values.

On the top–antitop invariant mass spectrum at the LHC from a Higgs boson signal perspective

We investigate the effect of one-loop corrections of O(αS2αW) on the tt¯ invariant mass spectrum at the Large Hadron Collider (LHC) in presence of both resonant and non-resonant Higgs boson effects. We show that corrections of O(αS2αW) involving a non-resonant Higgs boson are comparable to or even larger than those involving interference with the s-channel resonant Higgs boson amplitude and that both of these are subdominant with respect to all other (non-Higgs) diagrams through that order. We also compute the contribution through O(αS2αW2) of resonant Higgs boson production (i.e. Higgs production via gg fusion) as well as the pure QCD ones of O(αS3). Altogether, we show that the well-known peak–dip structure of the Mtt¯ spectrum emerging from interference effects between the t,u-channel gg-induced Leading Order (LO) QCD diagrams and the one due to a Higgs boson in s-channel via gg-fusion is drastically swamped by the remainder of the terms of O(αS2αW) discussed above.