S = number of events for the signal B = number of events for the background 2σ, bet a lunch 3σ, (Evidence), bet a bike 4σ, bet a used car 5σ, (Discovery), bet a house
The Minimal Supersymmetric Model
In the minimal supersymmetric standard model (MSSM), there are two Higgs doublet with vacuum expectation value (VEVs) v1 and v2, and five Higgs bosons: two scalars H0 and h0, one pseudoscalar A0, and a pair of singly charged Higgs bosons H±. At the tree level, mh ≤ MZ 91 GeV 95 GeV/c2
Higgs Decays into Leptons
In two Higgs doublet models with Model II of Yukawa couplings the φ0bb coupling is proportional to 1/cosβ, where tanβ ≡ v2/v1, and v1,2 are the vacuum expectations values of the Higgs fields. It is very promising to search for neutral Higgs bosons (φ0 = h0, H0, and A0) via their decays into leptons, φ0→ τ+τ and + at the LHC. The cross section of gg → bbφ0 is greatly enhanced in hadron collisions by a large tanβ. The contribution from qq → bbφ0 is usually negligible at hadron colliders.
Production of Higgs Bosons
A. Gluon Fusion: gg → φ0 B. Bottom Quark Fusion: bb → φ0 σ( gg → φ0bb)[mb(Mb)] ≈ 3σ( gg → φ0bb)[mb(Mφ)], Mφ = 200 GeV
σ( gg → φ0bb) ≈ σ( bb → φ0), F= Mφ/4
S. Dawson, C.B. Jackson, L. Reina, D. Wackeroth (2003 & 2004); V. Ravindran, J. Smith, and W.L. van Neerven (2003); R.V. Harlander & W.B. Kilgore (2002); C. Anastasiou & K. Melnikov (2002). M. Spira, A. Djouadi, D. Graudenz, P.M. Zerwas (1995). T. Plehn (2002); F. Maltoni, Z. Sullivan and S. Willenbrock (2003); E. Boos and T. Plehn (2003); R.V. Harlander and W.B. Kilgore (2003). B. Plumper, DESY-THESIS-2002-005.
Harlander and Kilgore (2002)
Higgs Boson Production via Bottom-Quark Fusion
The dominant subprocess for the production of a Higgs boson in association with bottom quarks is bottom-quark fusion bb → φ0. If we require one bottom quark at high pT from the production process, the leading-order subprocess should become bg → bφ0. For the production of the Higgs boson accompanied by two high pT b quarks, the leading subprocess should be gg,qq → bbφ0.

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