Dihadron fragmentation function and its evolution

Abstract

Dihadron fragmentation functions and their evolution are studied in the process of e + e − annihilation. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at leading order (LO) is shown to factorize into a short distance parton cross section and a long distance dihadron fragmentation function. We provide the definition of such a dihadron fragmentation function in terms of parton matrix elements and derive its DGLAP evolution equation 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.

HighpThadron–hadron correlations

“…This constitutes a rather involved procedure; the reader is referred to Ref. [5] for details. The resulting DGLAP evolution consists of two parts.…”

A comparative study of jet-quenching schemes

“…The determined constant, C, may be used to calculate the average energy loss encountered by a jet. Another advantage of this approach is the straightforward generalization to multiparticle correlations [11] and their modification in the medium.…”

“…To demonstratively distinguish between the various schemes requires the use of differential probes (beyond leading hadrons) emanating from the same jet. To date, such calculations have been performed at the integrated level [11,32]. In the left panel of Fig.…”

“…These large fields, transverse to the beam, tend to deflect radiated gluons from a transversely traveling jet, preferentially, Figure 5. Left: The near side associated yield as a function of centrality of collision [11]. Center: the associated gluon distribution in azimuth and pseudo-rapidity from a hard jet just after production(Initial) and at exit from a medium with turbulent transverse fields (Final) [37].…”

Dihadron fragmentation functions and highpThadron–hadron correlations

“…Under this approximation, at leading twist, we can demonstrate the factorization of the two-hadron inclusive cross section into a hard total partonic cross section σ 0 and the double inclusive fragmentation function D h1h2 q (z 1 , z 2 ) (see Ref. [6] for details),…”