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arXiv · 1802.00962

Recursive model for the fragmentation of polarized quarks

A. Kerbizi·X. Artru·Z. Belghobsi·F. Bradamante·A. Martin
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Abstract

We present a model for Monte Carlo simulation of the fragmentation of a polarized quark. The model is based on string dynamics and the ${}^3P_0$ mechanism of quark pair creation at string breaking. The fragmentation is treated as a recursive process, where the splitting function of the subprocess $q \to h + q'$ depends on the spin density matrix of the quark $q$. The ${}^3P_0$ mechanism is parametrized by a complex mass parameter $\mu$, the imaginary part of which is responsible for single spin asymmetries. The model has been implemented in a Monte Carlo program to simulate jets made of pseudoscalar mesons. Results for single hadron and hadron pair transverse-spin asymmetries are found to be in agreement with experimental data from SIDIS and $e^+e^-$ annihilation. The model predictions on the jet-handedness are also discussed.

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A. Kerbizi, X. Artru, Z. Belghobsi, F. Bradamante, A. Martin. 2018-02-03. Recursive model for the fragmentation of polarized quarks. https://doi.org/10.1103/physrevd.97.074010

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