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Next-to-leading order QCD corrections to pp-->ttbb+X at the LHC
A Bredenstein1, A Denner, S Dittmaier
1High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan.
Physical Review Letters
|August 8, 2009
Summary
We calculated quantum chromodynamics corrections for top quark-antiquark pair (tt) along with bottom quark-antiquark pair (bb) production at the Large Hadron Collider. These calculations improve background predictions for Higgs boson studies.
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Chromodynamics
Background:
- The production of top quark-antiquark pairs alongside bottom quark-antiquark pairs (ttbb) is a significant background process at the Large Hadron Collider (LHC).
- Accurate theoretical predictions are crucial for analyzing experimental data, particularly for processes involving Higgs boson production in association with top quark pairs (ttH).
Purpose of the Study:
- To compute the full next-to-leading-order (NLO) quantum chromodynamics (QCD) corrections to ttbb production at the LHC.
- To assess the impact of these corrections on theoretical predictions and their role as a background in precision measurements.
Main Methods:
- Full next-to-leading-order (NLO) calculations in quantum chromodynamics (QCD).
- Analysis of the ttbb production cross section and its scale dependence.
- Evaluation of the K factor, representing the ratio of NLO to leading-order cross sections.
Main Results:
- The full NLO QCD corrections to ttbb production have been calculated.
- These corrections significantly reduce the theoretical uncertainties associated with the scale dependence of the leading-order cross section.
- A substantial enhancement of the ttbb production cross section is predicted, with a K factor of approximately 1.8.
Conclusions:
- The inclusion of NLO QCD corrections is essential for precise theoretical predictions of ttbb production.
- These improved calculations enhance the reliability of background estimations for processes like ttH production at the LHC.
- The results provide a more robust theoretical framework for interpreting LHC data in high-energy physics.
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