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arXiv · 2203.13579

Extracting the $\Lambda$ Polarizing Fragmentation Function from Belle $e^+e^-$ Data Within the TMD Formalism

Marco Zaccheddu·Umberto D'Alesio·Leonard Gamberg·Francesco Murgia
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Abstract

Data from the Belle Collaboration for associated production (with a light unpolarized hadron) and single-inclusive production of transversely polarized $\Lambda$-hyperons in $e^+e^-$ annihilation processes allowed to extract within a TMD approach, for the first time, the $\Lambda$ polarizing fragmentation function. Recent theoretical developments on the computation of cross sections for single-inclusive hadron production in $e^+e^-$ annihilation processes, within a Soft Collinear Effective Theory approach, combined with the CSS formalism for the double-hadron production case, can be used to perform a renewed analysis, adopting a full TMD factorization scheme. Preliminary results and a comparison between the two analyses are presented.

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Marco Zaccheddu, Umberto D'Alesio, Leonard Gamberg, Francesco Murgia. 2022-03-25. Extracting the $\Lambda$ Polarizing Fragmentation Function from Belle $e^+e^-$ Data Within the TMD Formalism. https://doi.org/10.7566/jpscp.37.020111

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