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arXiv · 1207.6420

A kT-dependent sea-quark density for the CASCADE Monte Carlo event generator

F. Hautmann·M. Hentschinski·H. Jung
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Abstract

Parton-shower event generators that go beyond the collinear-ordering approximation at small x have so far included only gluon and valence quark channels at transverse momentum dependent level. We describe results of recent work to include effects of the sea-quark distribution with explicit dependence on the transverse quark-momentum.This sea-quark density is then applied to the description of forward Z -production. The qq*->Z matrix element (with one off-shell quark) is calculated in an explicit gauge invariant way, making use of high energy factorization. The kT-factorized result has been implemented into the CCFM Monte-Carlo CASCADE and a numerical comparison with the qg*->Zq matrix element has been carried out.

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F. Hautmann, M. Hentschinski, H. Jung. 2012-07-26. A kT-dependent sea-quark density for the CASCADE Monte Carlo event generator. https://arxiv.org/abs/1207.6420

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