Two-Loop g -> gg Splitting Amplitudes in QCD

Details Two-Loop g -> gg Splitting Amplitudes in QCD Two-Loop g -> gg Splitting Amplitudes in QCD

2004-04-30

arxiv.org/abs/hep-ph/0404293v2

JHEP 0408:012,2004

Physics

High Energy Physics

High Energy Physics - Phenomenology

100 pages, 33 figures. Added remarks about leading-transcendentality argument of hep-th/0404092, and additional explanation of

Scientific paper

10.1088/1126-6708/2004/08/012

Splitting amplitudes are universal functions governing the collinear behavior of scattering amplitudes for massless particles. We compute the two-loop g -> gg splitting amplitudes in QCD, N=1, and N=4 super-Yang-Mills theories, which describe the limits of two-loop n-point amplitudes where two gluon momenta become parallel. They also represent an ingredient in a direct x-space computation of DGLAP evolution kernels at next-to-next-to-leading order. To obtain the splitting amplitudes, we use the unitarity sewing method. In contrast to the usual light-cone gauge treatment, our calculation does not rely on the principal-value or Mandelstam-Leibbrandt prescriptions, even though the loop integrals contain some of the denominators typically encountered in light-cone gauge. We reduce the integrals to a set of 13 master integrals using integration-by-parts and Lorentz invariance identities. The master integrals are computed with the aid of differential equations in the splitting momentum fraction z. The epsilon-poles of the splitting amplitudes are consistent with a formula due to Catani for the infrared singularities of two-loop scattering amplitudes. This consistency essentially provides an inductive proof of Catani's formula, as well as an ansatz for previously-unknown 1/epsilon pole terms having non-trivial color structure. Finite terms in the splitting amplitudes determine the collinear behavior of finite remainders in this formula.

Affiliated with

Also associated with

No associations

Rating

Two-Loop g -> gg Splitting Amplitudes in QCD does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Two-Loop g -> gg Splitting Amplitudes in QCD, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two-Loop g -> gg Splitting Amplitudes in QCD will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-286989