Observation of tt¯H Production

Abstract

The observation of Higgs boson production in association with a top quark-antiquark pair is reported, based on a combined analysis of proton-proton collision data at center-of-mass energies of sqrt[s]=7, 8, and 13 TeV, corresponding to integrated luminosities of up to 5.1, 19.7, and 35.9 fb^{-1}, respectively. The data were collected with the CMS detector at the CERN LHC. The results of statistically independent searches for Higgs bosons produced in conjunction with a top quark-antiquark pair and decaying to pairs of W bosons, Z bosons, photons, τ leptons, or bottom quark jets are combined to maximize sensitivity. An excess of events is observed, with a significance of 5.2 standard deviations, over the expectation from the background-only hypothesis. The corresponding expected significance from the standard model for a Higgs boson mass of 125.09 GeV is 4.2 standard deviations. The combined best fit signal strength normalized to the standard model prediction is 1.26_{-0.26}^{+0.31}.

Threshold cusps and triangle singularities in hadronic reactions

“…TS contributions [442,448]. More importantly, the existence of the X(5568) was not confirmed in several subsequent experiments [449][450][451][452]. In contrast, the DK and BK S-wave interactions in the isospin-0 channel are generally supposed to be strong and attractive enough to generate a bound state corresponding to the D * s0 (2317) and its bottom partner, see, e.g., Ref.…”

Connecting Electroweak Symmetry Breaking and Flavor: A Light Dilaton D and a Sequential Heavy Quark Doublet Q

“…For CMS [52], based on H decay to the five modes of WW˚, ZZ˚, γγ, τ`τ´and bb, and combining 2016 data with Run 1, the measurement of µ ttH " 1. 26 So, what to make of the available 13 TeV results?…”

Associated production of SM Higgs with a photon in type-II seesaw models at the ILC

“…In the HTM, it is well known that once the triplet vev gets larger enough, v ∆ ≥ 10 −4 GeV, the bosonic decay mode H ±± → W ± W ± becomes larger than BR(H ±± → l ± l ± ). At the LHC, CMS with 8 TeV [47] and 13 TeV [48] search for pp → W * W * → H ±± → W ± W ± + X in the framework of Georgi-Machacek (GM) model and set a limit on the doublettriplet mixing angle s H (= sin θ H ) = 2 √ 2v χ /v where v χ is the triplet vev in the GM model. Since in the HTM H ±± W ± W ± = ig 2 v s β / √ 2 and H ±± W ± W ± = ig 2 v s H / √ 2 in the GM, it is clear that the equivalent of s H in the HTM is s β that can be obtained from Eq.…”