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Extrapolating parton fragmentation to low $Q^2$ in $e^+$-$e^-$ collisions

Thomas A. Trainor·David T. Kettler
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Abstract

We analyze the energy scale dependence of fragmentation functions from $e^+$-$e^-$ collisions using conventional momentum measures $x_p$ and $ξ_p$ and rapidity $y$. We find that replotting fragmentation functions on a normalized rapidity variable results in a compact form precisely represented by the beta distribution, its two parameters varying slowly and simply with parton energy scale $Q$. The resulting parameterization enables extrapolation of fragmentation functions to low $Q$ in order to describe fragment distributions at low transverse momentum $p_t$ in heavy ion collisions at RHIC.

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Thomas A. Trainor, David T. Kettler. 2006-07-19. Extrapolating parton fragmentation to low $Q^2$ in $e^+$-$e^-$ collisions. https://doi.org/10.1103/physrevd.74.034012

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