Higgs Production in Association with Bottom Quarks at Hadron Colliders

TL;DR

Higgs boson production in association with bottom quarks at hadron colliders is explored with a focus on MSSM scenarios at large tan beta. The work compares four-flavor and five-flavor number schemes, incorporates NLO QCD corrections and Delta_b SUSY corrections to the bottom Yukawa coupling, and assesses PDF and scale uncertainties across inclusive, semi-inclusive, and exclusive final states. Key findings show broad agreement between 4FNS and 5FNS within uncertainties, with NLO stabilizing predictions and MSSM rates greatly enhanced at large tan beta; PDF uncertainties are non-negligible and comparable to scale uncertainties in some regimes. The results provide robust predictions essential for Higgs searches and parameter determination at the Tevatron and LHC, clarifying the role of bottom-quark tagging in extracting Yukawa-proportional cross sections.

Abstract

We review the present status of the QCD corrected cross sections and kinematic distributions for the production of a Higgs boson in association with bottom quarks at the Fermilab Tevatron and CERN Large Hadron Collider. Results are presented for the Minimal Supersymmetric Standard Model where, for large tan beta, these production modes can be greatly enhanced compared to the Standard Model case. The next-to-leading order QCD results are much less sensitive to the renormalization and factorization scales than the lowest order results, but have a significant dependence on the choice of the renormalization scheme for the bottom quark Yukawa coupling. We also investigate the uncertainties coming from the Parton Distribution Functions and find that these uncertainties can be comparable to the uncertainties from the remaining scale dependence of the next-to-leading order results. We present results separately for the different final states depending on the number of bottom quarks identified.

Figures (16)

• Figure 1: Sample Feynman diagrams for $gg\rightarrow b\bar{b}h$ and $q\bar{q}\rightarrow b\bar{b}h$ production at tree level.
• Figure 2: Tree level Feynman diagram for $bg\rightarrow bh$ in the 5FNS.
• Figure 3: Tree level Feynman diagram for $b\bar{b}\rightarrow h$ in the 5FNS.
• Figure 4: Sample Feynman diagrams for the closed top quark loop contribution to $gg\rightarrow b\bar{b}h$. The circled cross denotes all possible insertion of the final state Higgs boson leg, each insertion corresponding to a different diagram.
• Figure 5: Total cross sections for $pp,p\bar{p}\rightarrow (b\bar{b})h$ ($h=h^0,H^0$) in the MSSM with no bottom quark jet identified in the final state in the 4FNS (at NLO) and 5FNS (at NLO and NNLO) as a function of the light and heavy MSSM Higgs boson masses, at both the Tevatron and the LHC. The error bands have been obtained by varying the renormalization and factorization scales as described in the text.