# The 24th International Spin Symposium

18-22 October 2021
Matsue, Shimane Prefecture, Japan
Asia/Tokyo timezone

## Longitudinal Spin Transfer to Lambda Hyperons in CLAS12

21 Oct 2021, 09:30
20m
Room 501 (Kunibiki Messe)

### Room 501

#### Kunibiki Messe

Parallel Session Presentation Nucleon Helicity Structure

### Speaker

Matthew McEneaney (Duke University)

### Description

Using the self analyzing decay of the $\Lambda^0$, the longitudinal spin transfer $D_{LL}$ from a polarized electron beam scattering an unpolarized proton target to the hyperon can be measured. 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 $\Lambda^0$. Currently, experimental data on $D_{LL}$ is limited and is not able to discriminate between different models of the $\Lambda^0$ spin structure. This contribution will report the status of the ongoing analysis of the longitudinal spin transfer using data taken by the CLAS12 experiment at Jefferson Lab, a large acceptance spectrometer using a 10.6 GeV electron beam. A focus of the analysis will be on the use of Graph Neural Networks (GNNs) to identify signal events.

### Primary author

Matthew McEneaney (Duke University)