BFKL at Next-to-Next-to-Leading Order
arXiv:0704.2404 · doi:10.1016/j.nuclphysb.2007.05.024
Abstract
We determine an approximate expression for the O(alpha_s^3) contribution chi_2 to the kernel of the BFKL equation, which includes all collinear and anticollinear singular contributions. This is derived using recent results on the relation between the GLAP and BFKL kernels (including running-coupling effects to all orders) and on small-x factorization schemes. We present the result in various schemes, relevant both for applications to the BFKL equation and to small-x evolution of parton distributions.
34 pages, 6 figures, TeX with harvmac. Various small typos corrects, in particular first term in eq D.3. Final version to be published in Nucl. Phys. B