Renormalon chain contributions to non-singlet evolution kernels in QCD

Contributions to QCD non-singlet forward evolution kernels P(z) for the DGLAP equation and to V(x,y) for nonforward (ER-BL) evolution equation are calculated for a certain class of diagrams which include renormalon chains. Closed expressions are presented for the sums of these contributions that dominate for a large number of flavors Nf≫1. Calculations are performed in covariant ξ-gauge, in the MS scheme. The assumption of “naive nonabelianization" approximation for kernel calculations is discussed. The partial solution to the ER-BL evolution equation is obtained.