Real-virtual corrections for gluon scattering at NNLO

Abstract

We use the antenna subtraction method to isolate the mixed real-virtual infrared singularities present in gluonic scattering amplitudes at next-to-next-to-leading order. In a previous paper, we derived the subtraction term that rendered the double real radiation tree-level process finite in the single and double unresolved regions of phase space. Here, we show how to construct the real-virtual subtraction term using antenna functions with both initial-and final-state partons which removes the explicit infrared poles present in the one-loop amplitude, as well as the implicit singularities that occur in the soft and collinear limits. As an explicit example, we write down the subtraction term that describes the single unresolved contributions from the five-gluon one-loop process. The infrared poles are explicitly and locally cancelled in all regions of phase space prior to integration, leaving a finite remainder that can be safely evaluated numerically in four-dimensions. We show numerically that the subtraction term correctly approximates the matrix elements in the various single unresolved configurations.

Parton distribution functions and benchmark cross sections at next-to-next-to-leading order

“…The calculation of the full NNLO QCD corrections to this process is still in progress (see Refs. [205,206] and references therein). This precludes a consistent use of the Tevatron jet data in our NNLO PDF fit.…”

Infrared sensitivity of single jet inclusive production at hadron colliders

“…A study of joint jet radius and threshold resummation has been presented in [23]. Progress in next-to-next-to-leading-order (NNLO) QCD calculations has been made over the past several years [24][25][26][27]. After the completion of the first calculations of the gluons-only subprocess [28,29], the complete leading-colour and leading-N F NNLO QCD corrections to the single jet inclusive production [30] and to di-jet production [31] were obtained recently.…”

May the four be with you: novel IR-subtraction methods to tackle NNLO calculations

“…This method has been derived in [108] and successfully applied to the calculation of the NNLO corrections to 3-jet production and related event shape observables in electron-positron annihilation in [183]. The extension of the scheme to the treatment of initial state radiation relevant for calculations of jet observables in hadronic collisions at LHC has been established at NLO in [109] and at NNLO in [133,[184][185][186][187][188][189][190]. In a first subsection we review the NLO version of the scheme followed by the generalisation to NNLO.…”