Observation of Transverse Λ/Λ Hyperon Polarization in e⁺e^- Annihilation at Belle

2016/11/21 by A. Abdesselam, The Belle Collaboration, I. Adachi +541
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions

paper · pdf · doi:10.48550/arxiv.1611.06648

openalex publication_date 2016/11/21 · openalex created_date 2024/04/10 · openalex updated_date 2026/07/28

Abstract

We report the first observation of the polarization of Λ/Λ hyperons transverse to its production plane in e⁺e^- annihilation. We observe a significant polarization that rises with the fractional energy carried by the hyperon as well as its transverse momentum. To define the production plane, we use the direction of the hyperon momentum together with either the thrust axis in the event or the momentum vector of a hadron in the opposite hemisphere. Furthermore, we investigate the contributions to the hyperon polarization from the feed-down from Σ⁰/Σ⁰ and Λ_c^± decays. This measurement uses a dataset of 800.4fb^-1 collected by the Belle experiment at or near a center-of-mass energy of 10.58 GeV.

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