Longitudinal Spin Transfer to $\Lambda$ Hyperons in CLAS12

Abstract

Using the self-analyzing decay of the $\Lambda$, the longitudinal spin transfer $D_{L{L}^{\prime }}$ to the hyperon from a polarized electron beam scattering off an unpolarized proton target can be determined. For $\Lambda$s produced in the current fragmentation region, this quantity is proportional to the helicity dependent fragmentation function $G_1^{\Lambda }$ and can provide insight into the spin structure of the $\Lambda$. Currently, limited experimental data on $D_{L{L}^{\prime }}$ cannot discriminate between different models of $\Lambda$ spin structure. This contribution reports on the status of the ongoing analysis of the longitudinal spin transfer using data taken by the CLAS12 spectrometer at Jefferson Lab with a 10.6 GeV polarized electron beam. We also report on the novel use of Graph Neural Networks (GNNs) to identify signal events.

References in corpus (5)

• Energy Flow Networks: Deep Sets for Particle Jets
• Observation of Transverse $\Lambda /\bar{\Lambda }$ Hyperon Polarization in $e^{+}{e}^{-}$ Annihilation at Belle
• Longitudinal Spin Transfer to the $\Lambda$ Hyperon in Semi-Inclusive Deep-Inelastic Scattering
• Observation of Beam Spin Asymmetries in the Process $ep\to e{\pi }^{+}{\pi }^{-}X$ with CLAS12
• Measurement of Lambda polarization in muon neutrino charged current interactions in NOMAD

Cited by in corpus (2)

• Suppression of Spin Transfer to $\Lambda$ Hyperon in Deep-Inelastic Scattering
• Longitudinal Spin Transfer to $\Lambda$ Hyperons in Semi-Inclusive Deep Inelastic Scattering with CLAS12