/ 97 10 20 5 v 1 1 O ct 1 99 7 TARGET FRAGMENTATION AND FRACTURE FUNCTIONS
نویسندگان
چکیده
We analyse recent data on the production of forward neutrons in deep inelastic scattering at HERA in the framework of a perturbative QCD description for semi-inclusive processes, which includes fracture functions. In the most naive quark-parton model picture, the semi-inclusive cross section for the production of a hadron h from the deep inelastic scattering of charged leptons is usually taken to be given by 1 : dσ h p dx dy dz h = (1 + (1 − y) 2) 2y 2 i=q,¯ q
منابع مشابه
v 1 1 5 O ct 1 99 6 CERN - TH / 96 - 261 Next to Leading Order QCD Corrections to Polarized Λ Production
We calculate next to leading order QCD corrections to semi-inclusive polarized deep inelastic scattering and e + e − annihilation cross sections for processes where the polarization of the identified final-state hadron can also be determined. Using dimensional regularization and the HVBM prescription for the γ 5 matrix, we compute corrections for different spin-dependent observables, both in th...
متن کاملFracture Functions: Factorization and Evolution
Fracture functions 1 have been introduced to extend the usual QCD improved parton picture of semi-inclusive deep inelastic processes to the low transverse momentum region of phase space, where the target fragmentation contribution becomes important. Trentadue and Veneziano 1 proposed to describe such contribution as a convolution of a new phenomenological distribution, the fracture function, wi...
متن کاملFracture functions in the very forward limit
This talk gives a brief discussion of extended fracture functions, which parametrise the non-perturbative physics in the target fragmentation region of semi-inclusive DIS. In the forward limit z → 1, it can be seen that fracture functions can be identified with insertions of composite operators. This enables polarised fracture functions to be used to test a target-independence hypothesis of the...
متن کاملSpin-dependent, interference and T−odd fragmentation and fracture functions
Fracture functions, originally suggested to describe the production of diffractive and leading hadrons in semi-inclusive DIS, may be also applied at fixed target energies. They may also include interference and final state interaction, providing a source for azimuthal asymmetries at HERMES and (especially) Λ polarization at NOMAD. The recent papers by Brodsky, Hwang and Schmidt, and by Gluck an...
متن کاملFracture Functions from Cut Vertices
Using a generalized cut vertex expansion we introduce the concept of an extended fracture function for the description of semi-inclusive deep inelastic processes in the target fragmentation region. Extended fracture functions are shown to obey a standard homogeneous DGLAP-type equation which, upon integration over t, becomes the usual inhomogeneous evolution equation for ordinary fracture funct...
متن کامل