BFKL at Next-to-Next-to-Leading Order

Understand

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.