Evolution of Chiral-Odd Nucleon Parton Distributions

We prove that the twist-3 chiral-odd parton distributions obey simple GLAP evolution equations in the limit N c ! 1 and give analytic results for the corresponding anomalous dimensions. To this end we introduce an evolution equation for the corresponding threeparticle twist-3 parton correlation functions and find an exact analytic solution. For large values of n (operator dimension) we are further able to collect all corrections subleading in N c , so our final results are valid to O(1=N 2 c \Delta ln(n)=n) accuracy. PACS numbers: 11.15.Pg, 11.10.Hi, 12.38.Bx, 13.85.Qk The increasing precision of experimental data from LEP, HERA and the TEVATRON requires understanding of corrections suppressed by powers of the large momentum, which are attributed to higher twist effects induced by correlations of partons in the colliding (produced) hadrons. The twist-3 parton distributions play a distinguished role in spin physics, where they can be measured as leading effects responsible for cert..