Observation of Higgs Boson Decay to Bottom Quarks

Abstract

The observation of the standard model (SM) Higgs boson decay to a pair of bottom quarks is presented. The main contribution to this result is from processes in which Higgs bosons are produced in association with a W or Z boson (VH), and are searched for in final states including 0, 1, or 2 charged leptons and two identified bottom quark jets. The results from the measurement of these processes in a data sample recorded by the CMS experiment in 2017, comprising 41.3 fb −1 of proton-proton collisions at √ s = 13 TeV, are described. When combined with previous VH measurements using data collected at √ s = 7, 8, and 13 TeV, an excess of events is observed at m H = 125 GeV with a significance of 4.8 standard deviations, where the expectation for the SM Higgs boson is 4.9. The corresponding measured signal strength is 1.01 ± 0.22. The combination of this result with searches by the CMS experiment for H → bb in other production processes yields an observed (expected) significance of 5.6 (5.5) standard deviations and a signal strength of 1.04 ± 0.20.

Higgs boson decay into a lepton pair and a photon revisited

“…A possible imprint of an extended Higgs sector are deviations of the measured couplings from their SM predictions [3]. To date CMS and ATLAS have studied the couplings of the dicovered Higgs boson to W [4][5][6][7] and Z [7][8][9][10] bosons, τ leptons [11][12][13], b [14,15] and t [16,17] quarks, as well as photons [18,19]. The latter coupling is loop-suppressed and has been probed though the rare decay H → γγ.…”

Higgs decay into massive b-quarks at NNLO QCD in the nested soft-collinear subtraction scheme

“…All tree-level amplitudes that we use in this paper are calculated using the spinorhelicity formalism. 3 The treatment of massive external particles follows along the lines of Appendix A of Ref. [60].…”

Safe use of jet pull

“…In particular, pinning down the couplings of the Higgs boson to the fermions may lead to a deeper understanding of the flavour structure of the SM. In this context, both the ATLAS and CMS collaborations have reached the sought-for statistical significance for the decay of the Higgs into bottom quarks [1,2] in Run II data.…”