Measurement of inclusive dijet cross-sections in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

TL;DR

This paper reports precise measurements of inclusive dijet cross-sections at 13 TeV using ATLAS data, comparing results with advanced QCD calculations to test the Standard Model and improve understanding of proton structure.

Contribution

First measurement of dijet cross-sections as functions of invariant mass and rapidity variables at 13 TeV with detailed comparison to NNLO QCD predictions.

Findings

Measured dijet cross-sections up to 10 TeV invariant mass.

Good agreement with NNLO QCD calculations after corrections.

Provides constraints on parton distribution functions.

Abstract

Inclusive dijet cross-sections have been measured in proton-proton collisions at a centre-of-mass energy of 13 TeV using data with an integrated luminosity of 140 fb$^{-1}$, recorded by the ATLAS detector at the Large Hadron Collider during 2015-2018. Jets are identified using the anti-$k_{t}$ algorithm with a radius parameter of $R = 0.4$. The inclusive dijet double-differential cross-sections are measured first as a function of the invariant dijet mass and the half absolute rapidity separation between the two leading jets, $(m_{\mathrm{jj}}$, $y^{\ast})$, and second as a function of the invariant dijet mass and the total longitudinal boost of the dijet system, $(m_{\mathrm{jj}}$, $y_{\mathrm{boost}})$. The measured dijet system covers the invariant mass range from 240 GeV to almost 10 TeV, with dijet separation $y^{\ast} < 3.0$ and dijet boost $y_{\mathrm{boost}} < 3.0$. The results are unfolded to the particle level and compared with state-of-the-art next-to-next-to-leading-order full colour perturbative QCD calculations, corrected for non-perturbative and electroweak effects.