Gabor Somogyi

A subtraction scheme for computing QCD jet cross sections at NNLO: regularization of doubly-real emissions

We present a generalization of the dipole subtraction scheme for computing jet cross sections in electron-positron annihilation at next-to-next-to-leading order accuracy in perturbative QCD. In this first part we deal with the regularization of the doubly-real contribution to the NNLO correction.

Matching of singly- and doubly-unresolved limits of tree-level QCD squared matrix elements

We describe how to disentangle the singly- and doubly-unresolved (soft and/or collinear) limits of tree-level QCD squared matrix elements. Using the factorization formulae presented in this paper, we outline a viable general subtraction scheme for computing next-to-next-to-leading order corrections for electron-positron annihilation into jets.

A subtraction scheme for computing QCD jet cross sections at NNLO: integrating the iterated singly-unresolved subtraction terms

We perform the integration of all iterated singly-unresolved subtraction terms, as defined in ref. [1], over the two-particle factorized phase space. We also sum over the unresolved parton flavours. The final result can be written as a convolution (in colour space) of the Born cross section and an insertion operator. We spell out the insertion operator in terms of 24 basic integrals that are defined explicitly. We compute the coefficients of the Laurent expansion of these integrals in two different ways, with the method of Mellin-Barnes representations and sector decomposition. Finally, we present the Laurent-expansion of the full insertion operator for the specific examples of electron-positron annihilation into two and three jets.

Analytic integration of real-virtual counterterms in NNLO jet cross sections. I.

We present analytic expressions of all integrals required to complete the explicit evaluation of the real-virtual integrated counterterms needed to define a recently proposed subtraction scheme for jet cross sections at next-to-next-to-leading order in QCD. We use the Mellin-Barnes representation of these integrals in 4 − 2ǫ dimensions to obtain the coefficients of their Laurent expansions around ǫ = 0. These coefficients are given by linear combinations of multidimensional Mellin-Barnes integrals. We compute the coefficients of such expansions in ǫ both numerically and analytically by complex integration over the Mellin-Barnes contours.We present analytic expressions of all integrals required to complete the explicit evaluation of the real-virtual integrated counterterms needed to define a recently proposed subtraction scheme for jet cross sections at next-to-next-to-leading order in QCD. We use the Mellin-Barnes representation of these integrals in

A Subtraction scheme for computing QCD jet cross sections at NNLO: Integrating the subtraction terms. I.

4-2\epsilon

Targeted drug delivery to the brain via phosphonate derivatives. I. Design, synthesis and evaluation of an anionic chemical delivery system for testosterone

dimensions to obtain the coefficients of their Laurent expansions around

Subtraction with hadronic initial states at NLO: an NNLO-compatible scheme

\epsilon=0

Three-Jet Production in Electron-Positron Collisions at Next-to-Next-to-Leading Order Accuracy

. These coefficients are given by linear combinations of multidimensional Mellin-Barnes integrals. We compute the coefficients of such expansions in

Higgs boson decay into b-quarks at NNLO accuracy

\epsilon

Targeted drug delivery to the brain via phosphonate derivatives. II. Anionic chemical delivery system for zidovudine (AZT)

both numerically and analytically by complex integration over the Mellin-Barnes contours.