Conference Presentation (Invited)

PUBDB-2026-00060

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Beam-spin induced polarization of $\Lambda$ and anti-$\Lambda$ hyperons in semi-inclusivedeep-inelastic scattering

Veretennikov, D. (Corresponding author)Extern* ; HERMES Collabration (Collaboration author)

2025

Abstract: The HERMES experiment has collected a wealth of data using the 27.6 GeV longitudinally polar- ized HERA lepton beam and various polarized and unpolarized gaseous targets. This allows for a series of unique measurements of observables sensitive to the multidimensional (spin) structure of the nucleon, in particular semi-inclusive deep-inelastic scattering (SIDIS) measurements, for which the HERMES dual-radiator ring-imaging Cherenkov counter provided final-hadron identification be- tween 2 GeV to 15 GeV for pions, kaons, and (anti)protons.Lambda hyperons in the final state give us the unique opportunity to study spin dependent effects through its polarization measurements using its weak decay channel. In this contribution, the longi- tudinal and transverse component of the spin transfer coefficient from the longitudinally polarized electron/positron beam to the lambda or antilambda hyperon alongside with kinematical depen- dences on Feyman- and Bjorken-x as well as the hyperon’s transverse momentum will be presented. These spin-transfer coefficients provide access to several spin-dependent fragmentation functions, which have been related to the inner structure of Λ hyperons. The results are also compared to similar measurements at the COMPASS and NOMAD experiments.

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Contributing Institute(s):

1. HERMES Kollaboration (HERMES)

Research Program(s):

1. 611 - Fundamental Particles and Forces (POF4-611) (POF4-611)

Experiment(s):

1. HERA: HERMES

Appears in the scientific report 2025

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