Dihadron fragmentation functions and highp_Thadron–hadron correlations

Abstract

Abstract. We propose the formulation of a dihadron fragmentation function in terms of parton matrix elements. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at leading order (LO) in e + e − annihilation is shown to factorize into a short distance parton cross section and the long distance dihadron fragmentation function. We also derive the DGLAP evolution equation of this function at leading log. The evolution equation for the non-singlet quark fragmentation function is solved numerically with a simple ansatz for the initial condition and results are presented for cases of physical interest.

Evolution of the parton dihadron fragmentation functions

“…(22) Note that both N and N (N −1) in Eqs. (14) and (15) are not infrared safe and therefore not well defined in the collinear approximation for the fragmentation functions. Consequently, these sum rules for dihadron fragmentation functions are also not well defined in collinear approximation.…”

“…The long distance objects or the inclusive n-hadron fragmentation functions contain the non-perturbative information of parton hadronization [1,9]. These fragmentation functions can be defined in an operator formalism [14,15] and hence are valid beyond the perturbative theory. They however cannot be calculated perturbatively and have to be instead inferred from experiments.…”