Measurement of inclusive jet cross-sections and search for resonances decaying into a photon and a jet

Abstract

Inclusive jet cross-sections are measured in proton-proton collisions at a centre-of-mass energy of 13 TeV.<br />The measurement uses a dataset with an integrated luminosity of 3.2 fb-1 recorded in 2015 with the ATLAS detector at the Large Hadron Collider.<br />Jets are identified using the anti-kt algorithm with a radius parameter value of R=0.4.<br />The inclusive jet cross-sections are measured double-differentially as a function of the jet transverse momentum, covering the range from 100 GeV to 3.5 TeV, and the absolute jet rapidity up to |y|=3.<br />Next-to-leading-order and next-to-next-to-leading-order perturbative quantum chromodynamics calculations corrected for non-perturbative and electroweak effects are compared to the measured cross-sections.<br />In addition, a search is performed for new phenomena in events having a photon with high transverse momentum and a jet collected in 36.7 fb-1 of proton-proton collisions at a centre-of-mass energy of sqrt(s) = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider.<br />The invariant mass distribution of the leading photon and jet is examined to look for the resonant production of new particles or the presence of new high-mass states beyond the Standard Model.<br />No significant deviation from the background-only hypothesis is observed and cross-section limits for generic Gaussian-shaped resonances are extracted.<br />Excited quarks hypothesised in quark compositeness models and high-mass states predicted in quantum black hole models with extra dimensions are also examined in the analysis.<br />The observed data exclude, at 95 % confidence level, the mass range below 5.3 TeV for excited quarks and 7.1 TeV (4.4 TeV) for quantum black holes in the Arkani-Hamed-Dimopoulos-Dvali (Randall-Sundrum) model with six (one) extra dimensions.