[Paper Review] Electroweak corrections to b-jet and di-jet production

Andreas Scharf|ArXiv.org|Oct 1, 2009

Particle physics theoretical and experimental studies8 references3 citations

TL;DR

This paper presents next-to-leading order electroweak corrections to b-jet and di-jet production at the LHC, calculating their impact on transverse momentum distributions. It finds significant negative weak corrections—reaching -10% to -14% at high pT—exceeding statistical uncertainties, particularly for single and double b-tag events, indicating detectable effects in precision QCD and BSM physics studies at 14 TeV LHC energies.

ABSTRACT

Simultaneously with the turning-on of the Large Hadron Collider (LHC) the data taking for jet production rates will start. The study of these production rates is an important test of the Standard Model in the new energy regime accessible at the LHC. In order to discriminate possible extensions of the Standard Model accurate theoretical predictions are needed. We investigate the next-to-leading order weak corrections for bottom-quark jet and di-jet production at the LHC and find detectable effects in transverse momentum distributions.

Motivation & Objective

• To compute next-to-leading order electroweak corrections for b-jet and di-jet production at the LHC.
• To assess the detectability of weak corrections in transverse momentum distributions for high-energy jet production.
• To evaluate whether electroweak effects surpass statistical uncertainties in experimental data.
• To compare the impact of weak corrections on single vs. double b-tagged events and di-jet final states.
• To provide precision theoretical predictions for testing the Standard Model and new physics at the TeV scale.

Proposed method

• Calculated weak corrections using a combination of virtual box diagrams and real radiation contributions at NLO in electroweak theory.
• Employed parton distribution functions (PDFs) and factorized cross sections via the convolution of partonic luminosities with partonic cross sections.
• Applied a transverse momentum cut of 50 GeV to simulate detector acceptance and exclude under-energetic jets.
• Used the leading-order differential cross section as a baseline, with corrections computed via subtraction of infrared divergences.
• Performed numerical evaluation at √s = 14 TeV and 10 TeV to compare energy dependence and signal strength.
• Estimated statistical uncertainties based on 200 fb⁻¹ luminosity to assess detectability of weak corrections.

Experimental results

Research questions

• RQ1 How significant are next-to-leading order electroweak corrections to b-jet production at the LHC?
• RQ2 Do weak corrections to b-jet transverse momentum distributions exceed statistical uncertainties in high-pT regions?
• RQ3 How do weak corrections differ between single and double b-tagged events in b-jet production?
• RQ4 What is the magnitude and shape of electroweak corrections for di-jet production at high pT?
• RQ5 Can electroweak effects be resolved in experimental data given current luminosity and sensitivity?

Key findings

• For single b-tag events, electroweak NLO corrections reduce the leading-order pT distribution by up to -14% at pT = 2 TeV.
• For double b-tag events, relative corrections reach -14% at pT = 2 TeV, with a distinct shape due to Sudakov logarithms and virtual top-quark contributions.
• Weak corrections exceed statistical uncertainties up to pT ≈ 1.5 TeV for single b-tag and remain larger than uncertainties up to 1 TeV for double b-tag events.
• The corrections are negative and grow in magnitude with increasing pT, dominated by Sudakov logarithms at high energies.
• For di-jet production, relative weak corrections are negative and reach -10% to -12% at pT > 1 TeV, with similar qualitative behavior to b-jet production.
• The impact of weak corrections remains qualitatively similar at √s = 10 TeV, though absolute cross sections are reduced by over a factor of two.