P Pbar to T Tbar H: A Discovery mode for the Higgs boson at the Tevatron

TL;DR

It is demonstrated that the production cross section times branching ratio for H-->bb macro decays yields a significant number of events and that this mode is competitive with and complementary to the searches using pp(macro) -->WH,ZH associated production.

Abstract

The production of a Standard Model Higgs boson in association with a top quark pair at the upcoming high luminosity run (15 inverse fb integrated luminosity) of the Fermilab Tevatron (root s = 2.0 TeV) is revisited. For Higgs masses below 140 GeV we demonstrate that the production cross section times branching ratio for H->B Bbar decays yields a significant number of events and that this mode is competitive with and complementary to the searches using P Pbar -> WH, ZH associated production. For higher mass Higgs bosons the H -> W+ W- decays are more difficult but have the potential to provide a few spectacular events.

Figures (2)

• Figure 1: For $p\bar{p}$ collisions at $\sqrt{s} = 2.0$ TeV: (a) cross section (pb) for various Higgs boson production modes Hobbs; (b) the $t\bar{t}H$ production cross section times branching ratio and K-factor (fb) for $H\to b\bar{b}$ (solid) and $H\to W^+W^-$ (dashed).
• Figure 2: (a) The $t\bar{t}H$ signal (solid) and $t\bar{t}+jets$ (including $t\bar{t}b\bar{b},t\bar{t}c\bar{c}$) background (dotted) distributions for the fourth-highest mass pair of $b$-tag candidates. This includes cases where a jet from the hadronic $W$ decay is misidentified as a $b$ jet. We cut on this distribution at $m_{bb} > 60$ GeV. (b) Invariant mass distribution of $b$-tag candidates after top quark pair reconstruction with efficiency $\epsilon_{rec} = 70\%$. For $M_H = 120$ GeV and 15 fb$^{-1}$ this corresponds to a $2.8\sigma$ significance for one experiment, or $4.1\sigma$ for two.