(2017) 'Next-to-next-to leading order QCD predictions for single jet inclusive production at the LHC.', Physical review letters., 118 (7). 072002.Further information on publisher's website:https://doi.org/10.1103/PhysRevLett.118.072002Publisher's copyright statement:Reprinted with permission from the American Physical Society: Currie, J., Glover, E.W.N. Pires, J. (2017). Next-to-Next-to Leading Order QCD Predictions for Single Jet Inclusive Production at the LHC. Physical Review Letters 118(7): 072002. c 2017 by the American Physical Society. Readers may view, browse, and/or download material for temporary copying purposes only, provided these uses are for noncommercial personal purposes. Except as provided by law, this material may not be further reproduced, distributed, transmitted, modi ed, adapted, performed, displayed, published, or sold in whole or part, without prior written permission from the American Physical Society.Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.

We use the antenna subtraction method to isolate the double real radiation infrared singularities present in gluonic scattering amplitudes at next-to-next-to-leading order. The antenna subtraction framework has been successfully applied to the calculation of NNLO corrections to the 3-jet cross section and related event shape distributions in electron-positron annihilation. Here we consider processes with two coloured particles in the initial state, and in particular two-jet production at hadron colliders such as the Large Hadron Collider (LHC). We construct a subtraction term that describes the single and double unresolved contributions from the six-gluon tree-level process using antenna functions with initial state partons and show numerically that the subtraction term correctly approximates the matrix elements in the various single and double unresolved configurations.

The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.

We report the calculation of next-to-next-to-leading order (NNLO) QCD corrections in the purely gluonic channel to dijet production and related observables at hadron colliders. Our result represents the first NNLO calculation of a massless jet observable at hadron colliders, and opens the path towards precision QCD phenomenology with the LHC.PACS numbers: 13.87. Ce,12.38Bx Single inclusive jet and dijet observables are the most fundamental QCD processes measured at hadron colliders. They probe the basic parton-parton scattering in 2 → 2 kinematics, and thus allow for a determination of the parton distribution functions in the proton and for a direct probe of the strong coupling constant α s up to the highest energy scales that can be attained in collider experiments.Precision measurements of single jet and dijet cross Theoretical predictions for these observables are accurate to next-to-leading order (NLO) in QCD [6][7][8][9][10] and the electroweak theory [11]. The estimated uncertainty from missing higher order corrections on the NLO QCD predictions is substantially larger than the experimental errors on single jet and dijet data, and is thus the dominant source of error in the determination of α s . A consistent inclusion of jet data in global fits of parton distributions is also feasible only to NLO. These theoretical limitations to precision phenomenology provide a very strong motivation for computing next-to-next-to-leading order (NNLO) corrections to jet production at hadron colliders.At this perturbative order, three types of parton-level processes contribute to jet production: the two-loop virtual corrections to the basic 2 → 2 process [12], the one-loop virtual corrections to the single real radiation 2 → 3 process [13] and the double real radiation 2 → 4 process at tree-level [14]. Each contribution is infrared divergent, and only their sum yields a finite and meaningful result. After ultraviolet renormalization, both virtual contributions contain explicit infrared singularities, which are compensated by infrared singularities from single or double real radiation. These become explicit only after integrating out the real radiation contributions over the phase space relevant to single jet or dijet production.This interplay with the jet definition complicates the extraction of infrared singularities from the real radiation process. It is typically done by subtracting an infrared approximation from the corresponding matrix elements. These infrared subtraction terms are sufficiently simple to be integrated analytically, such that they can be combined with the virtual contributions to obtain the cancellation of all infrared singularities. Several generic methods for the construction of subtraction terms are available at NLO [15][16][17].The development of subtraction methods for NNLO calculations is a very active field of research. Up to now, various methods were constructed and applied to specific NNLO calculations of exclusive observables: sector decomposition [18] The antenna subtraction method [27,...

The Large Hadron–Electron Collider (LHeC) is designed to move the field of deep inelastic scattering (DIS) to the energy and intensity frontier of particle physics. Exploiting energy-recovery technology, it collides a novel, intense electron beam with a proton or ion beam from the High-Luminosity Large Hadron Collider (HL-LHC). The accelerator and interaction region are designed for concurrent electron–proton and proton–proton operations. This report represents an update to the LHeC’s conceptual design report (CDR), published in 2012. It comprises new results on the parton structure of the proton and heavier nuclei, QCD dynamics, and electroweak and top-quark physics. It is shown how the LHeC will open a new chapter of nuclear particle physics by extending the accessible kinematic range of lepton–nucleus scattering by several orders of magnitude. Due to its enhanced luminosity and large energy and the cleanliness of the final hadronic states, the LHeC has a strong Higgs physics programme and its own discovery potential for new physics. Building on the 2012 CDR, this report contains a detailed updated design for the energy-recovery electron linac (ERL), including a new lattice, magnet and superconducting radio-frequency technology, and further components. Challenges of energy recovery are described, and the lower-energy, high-current, three-turn ERL facility, PERLE at Orsay, is presented, which uses the LHeC characteristics serving as a development facility for the design and operation of the LHeC. An updated detector design is presented corresponding to the acceptance, resolution, and calibration goals that arise from the Higgs and parton-density-function physics programmes. This paper also presents novel results for the Future Circular Collider in electron–hadron (FCC-eh) mode, which utilises the same ERL technology to further extend the reach of DIS to even higher centre-of-mass energies.

We use the antenna subtraction method to isolate the double virtual infrared singularities present in gluonic scattering amplitudes at next-to-next-to-leading order. In previous papers, we derived the subtraction terms that rendered (a) the double real radiation tree-level process finite in the single and double unresolved regions of phase space and (b) the mixed single real radiation one-loop process both finite and well behaved in the unresolved regions of phase space. Here, we show how to construct the double virtual subtraction term using antenna functions with both initial-and final-state partons which remove the explicit infrared poles present in the two-loop amplitude. As an explicit example, we write down the subtraction term for the four-gluon two-loop process. The infrared poles are explicitly and locally cancelled in all regions of phase space leaving a finite remainder that can be safely evaluated numerically in four-dimensions.

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We present the next-to-next-to-leading order (NNLO) QCD corrections to dijet production in the purely gluonic channel retaining the full dependence on the number of colours. The sub-leading colour contribution in this channel first appears at NNLO and increases the NNLO correction by around 10% and exhibits a p T dependence, rising from 8% at low p T to 15% at high p T . The present calculation demonstrates the utility of the antenna subtraction method for computing the full colour NNLO corrections to dijet production at the Large Hadron Collider.