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arXiv · 2003.01128

First extraction of the $Λ$ polarising fragmentation function from Belle $e^+e^-$ data

Umberto D'Alesio·Francesco Murgia·Marco Zaccheddu
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Abstract

We present a thorough phenomenological analysis of the experimental data from Belle Collaboration for the transverse $Λ$ and $\barΛ$ polarisation, measured in $e^+e^-$ annihilation processes, for the case of inclusive (plus a jet) and associated production with a light charged hadron. This allows for the first ever extraction of the quark polarising fragmentation function for a $Λ$ hyperon, a transverse momentum dependent distribution giving the probability that an unpolarised quark fragments into a transversely polarised spin-1/2 hadron.

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Umberto D'Alesio, Francesco Murgia, Marco Zaccheddu. 2020-03-02. First extraction of the $Λ$ polarising fragmentation function from Belle $e^+e^-$ data. https://doi.org/10.1103/physrevd.102.054001

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