Search for two Higgs bosons in final states containing two photons and two bottom quarks in proton-proton collisions at 8 TeV

Abstract

A search is presented for the production of two Higgs bosons in final states containing two photons and two bottom quarks. Both resonant and nonresonant hypotheses are investigated. The analyzed data correspond to an integrated luminosity of 19.7 fb −1 of proton-proton collisions at ffiffi ffi s p ¼ 8 TeV collected with the CMS detector. Good agreement is observed between data and predictions of the standard model (SM). Upper limits are set at 95% confidence level on the production cross section of new particles and compared to the prediction for the existence of a warped extra dimension. When the decay to two Higgs bosons is kinematically allowed, assuming a mass scale Λ R ¼ 1 TeV for the model, the data exclude a radion scalar at masses below 980 GeV. The first Kaluza-Klein excitation mode of the graviton in the RS1 Randall-Sundrum model is excluded for masses between 325 and 450 GeV. An upper limit of 0.71 pb is set on the nonresonant two-Higgs-boson cross section in the SM-like hypothesis. Limits are also derived on nonresonant production assuming anomalous Higgs-boson couplings.

Maximizing the significance in Higgs boson pair analyses

“…Unlike in the CMS study of Ref. [15] we only consider the high-purity category where both b-jets are tagged and which should dominate the significance at the high-luminosity LHC. Following Ref.…”

“…Following Ref. [5] and the CMS study [15] main backgrounds are the nonresonant γγ þ 2 jets process-including γγcc-and γj þ 2 jets production. Throughout our analysis we will see that these QCD continuum backgrounds have essentially the same shape, while their relative size depends on the photon and bottom identification.…”

“…Our choice of trigger cuts is motivated by CMS [15]: p T;γ 1 >m γγ =3≈41GeV, p T;γ 2 >m γγ =4≈31GeV, jη γ j < 2.5, ΔR γγ;γj;jj > 0.4, m γγ ¼ 100…180 GeV, p T;j > 25 GeV, jη j j < 2.4, and m jj ¼ 60…180 GeV. Our invariant mass windows m bb ¼ 80…160 GeV and m γγ ¼ 120…130 GeV are designed to fully contain the peaks, as illustrated in the first two panels of Fig.…”

“…The most promising channel for a SM-like pair of Higgs bosons is most likely the bbγγ final state [5,[13][14][15]. Its great advantage is that we can easily reconstruct one of the two Higgs bosons and that the QCD continuum background can be measured in control regions.…”

Searching for dark photons with maverick top partners

“…• Scalar: The addition of a new scalar shifts Higgs boson couplings away from SM predictions, as well as contributing to new loop contributions to EW precision parameters. Additionally, many searches have been performed for new scalar production at the LHC [62][63][64][65][66][67][68] as well as at LEP [69][70][71]. However, the most stringent constraints [72] come from precision measurements of the observed M 1 = 125 GeV Higgs boson for M 1 M 2 650 GeV and precision W -mass constraints [51,52,73] for 650 GeV M 2 1 TeV.…”