Precise Predictions for Dijet Production at the LHC.

Area of Science:

• High Energy Physics
• Quantum Chromodynamics
• Particle Physics

Background:

• Dijet production is a fundamental process in high-energy particle collisions.
• Previous calculations at next-to-leading order (NLO) faced challenges with theoretical scale choices.
• Understanding dijet production is crucial for testing the Standard Model and searching for new physics.

Purpose of the Study:

• To perform a next-to-next-to-leading order (NNLO) calculation for dijet production.
• To address the scale-setting problems encountered at NLO.
• To provide reliable theoretical predictions for comparison with experimental data.

Main Methods:

• Calculation of dijet production cross-sections in all partonic channels at NNLO.
• Investigation of different theoretical scale choices and their impact on predictions.
• Comparison of theoretical results with experimental data from ATLAS at the Large Hadron Collider.

Main Results:

• The NNLO calculation resolves the pathological behavior observed at NLO for certain scale choices.
• Dijet invariant mass is identified as a suitable theoretical scale for perturbative convergence.
• The NNLO predictions show good agreement with the ATLAS 7 TeV data.

Conclusions:

• NNLO perturbative QCD calculations offer robust and reliable predictions for dijet production.
• The improved theoretical accuracy allows for more precise tests of the Standard Model.
• This work provides a foundation for future precision studies of electroweak and beyond-Standard-Model physics.