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

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.

Comments: 6 pages, 2 figures (5 plots), presented by M. Zaccheddu at the 24th International Spin Symposium (SPIN2021), 18-22 October 2021, Matsue, Japan