Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

Abstract

A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons () in proton-proton collisions collected by the CMS experiment at the LHC at . The data correspond to an integrated luminosity of 19.7. The search considers resonances with masses between 1 and 3, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 % confidence level for the product of the production cross section and branching fraction range from 10 to 1.5 for the mass of X from 1.15 to 2.0, significantly extending previous searches. For a warped extra dimension theory with a mass scale , the data exclude radion scalar masses between 1.15 and 1.55.

Dichroic subjettiness ratios to distinguish colour flows in boosted boson tagging

“…[7][8][9][10][11] for recent examples). The third, "dichroic", option is a new combination, and is the subject of this paper.…”

“…The third, "dichroic", option is a new combination, and is the subject of this paper. 9 To understand how these different variants work, we will take two approaches. First we will consider what values of τ 21 arise for different kinematic configurations involving three particles in the jet, i.e.…”

“…In each case, figure 4 gives the result for each of the τ 21 variants, for both background and signal. The signal case simply assumes that there are no emissions 9 One can be tempted to also consider a fourth option where τ1 is computed on the full jet and τ2 on the tagged jet. It is straightforward to show, following the same arguments as below, that this is not the best combination, as one might expect intuitively.…”

“…The resulting dichroic τ 2 /τ 1 ratio gives enhanced performance compared to existing uses of N -subjettiness, which adopt the same (sub)jet for numerator and denominator (see e.g. [7][8][9][10][11] for recent examples).…”

The minimal stealth boson: models and benchmarks

“…These tools allow to distinguish jets originating from boosted hadronically-decaying bosons and top quarks from the Standard Model (SM) background, composed mainly by quark and gluon jets produced in QCD processes. In this way, searches for diboson [18][19][20][21][22][23][24], tt [25] and tb [26,27] resonances in purely hadronic channels have been performed, with a sensitivity that turns out to be competitive with channels involving leptons in the final state. Nevertheless, these searches are insensitive to heavy resonances decaying into more complex hadronic final states, giving rise to multi-pronged jets.…”