Related papers: NNLO Photon Fragmentation within Antenna Subtracti…
The alternative approach to QCD analysis of the photon structure function $F_2^{\gamma}$ is presented. It differs from the conventional one by the presence of the terms which in conventional approach appear in higher orders. We show that…
In this paper we present a next-to-next-to-leading order (NNLO) calculation of the process $pp\rightarrow \gamma\gamma$ that we have implemented into the parton level Monte Carlo code MCFM. We do not find agreement with the previous…
We apply the so-called conformal subtraction scheme to predict perturbatively exclusive processes beyond leading order. Taking into account evolution effects, we study the scheme dependence for the photon-to-pion transition form factor and…
We study inclusive photoproduction of hadrons at HERA via both direct and resolved photons to next-to-leading order (NLO) in the QCD-improved parton model. We predict transverse-momentum ($\pt$) and rapidity ($\ylab$) distributions and…
We suggest improvements for double counting subtraction scheme, which is needed for the consistent treatment of real corrections in the high-energy limit, and apply it to the single photon production at the NLO${}^\star$ approximation of…
The singularities associated with QCD factorization in the collinear limit are key ingredients for high-precision theoretical predictions in particle physics. They govern the collinear behaviour of scattering amplitudes, as well as the…
We present splitting functions in the triple collinear limit at next-to-leading order in the strong coupling. We performed the computation in the context of massless QCD+QED, and consider first collinear processes which include at least one…
We present the next-to-leading order QCD corrections to the production of a photon pair in association with one or two jets. This class of processes constitutes an important background for Higgs physics at the LHC. For the one jet process…
We propose a framework for the implementation of a subtraction formalism at NNLO in QCD, based on an observable- and process-independent cancellation of infrared singularities. As a first simple application, we present the calculation of…
We present a general subtraction scheme for NNLO calculations in massless QCD: the \textit{colourful antenna subtraction method}. It is a reformulation of the antenna subtraction approach designed to address some of the limitations of the…
We consider QCD radiative corrections to the production of W and Z bosons in hadron collisions. We present a fully exclusive calculation up to next-to-next-to-leading order (NNLO) in QCD perturbation theory. To perform this NNLO…
Beam and jet functions in Soft-Collinear Effective Theory describe collinear initial- and final-state radiation (jets), and enter in factorization theorems for N-jet production, the Higgs pT spectrum, etc. We show that they may directly be…
We discuss the problems that arise when one wishes to extend the existing general methods of computing radiative corrections to QCD jet cross sections to beyond next-to-leading order. Then we present a subtraction scheme that can be defined…
Fragmentation functions are determined for the pion, kaon, and proton by analyzing charged-hadron production data in electron-positron annihilation. It is important that uncertainties of the determined fragmentation functions are estimated…
We describe how the nested soft-collinear subtraction scheme [1] can be used to compute the next-to-next-to-leading order (NNLO) QCD corrections to the production of an arbitrary number of gluonic jets in hadron collisions. We show that the…
We propose a new subtraction scheme for next-to-leading order QCD calculations. Our scheme is based on the momentum mapping and on the splitting functions derived in the context of an improved parton shower formulation. Compared to standard…
The NLO QCD calculation for the photoproduction of the isolated photon with a large $p_T$ at the HERA $ep$ collider is presented. The single resolved photon contribution and the QCD corrections of order $\alpha_s$ to the Born term are…
We review standard subtraction, as a method to compute cross sections at NNLO accuracy.
Within the NRQCD factorization framework, we compute the next-to-leading-order QCD corrections to the gluon fragmentation into the ${}^1S_0^{(1,8)}$ Fock components of a quarkonium, at the lowest order in velocity expansion. We follow the…
The interpretation of experimental measurements at the LHC requires accurate theoretical predictions for exclusive observables, and in particular the summation of soft and collinear radiation to all orders in perturbation theory. We report…