Measurement of double polarized asymmetries in quasi-elastic processes ${}^3\vec{He}(\vec{e},e' d)$ and ${}^3\vec{He}(\vec{e},e' p)$

TL;DR

This thesis reports on precise measurements of double polarized asymmetries in quasi-elastic ${}^3 ext{He}$ reactions, providing insights into its spin structure and testing advanced theoretical models.

Contribution

It presents new experimental data on asymmetries in polarized ${}^3 ext{He}$ reactions, improving understanding of its ground-state wave-functions and comparing results with Faddeev calculations.

Findings

Measured asymmetries $A_x$ and $A_z$ across recoil momenta

Compared experimental results with theoretical Faddeev calculations

Identified open problems for future research

Abstract

This thesis is dedicated to a study of a spin-isospin structure of the polarized ${}^3\mathrm{He}$. First, an introduction to the spin structure of ${}^3\mathrm{He}$ is given, followed by a brief overview of past experiments. The main focus of the thesis is the E05-102 experiment at Jefferson Lab, in which the reactions ${}^3\vec{\mathrm{He}}(\vec{\mathrm{e}},\mathrm{e'} \mathrm{d})$ and ${}^3\vec{\mathrm{He}}(\vec{\mathrm{e}},\mathrm{e'} \mathrm{p})$ in the quasi-elastic region were studied. The purpose of this experiment was to better understand the effects of the S'- and D-state contributions to the ${}^3\mathrm{He}$ ground-state wave-functions by a precise measurement of beam-target asymmetries $A_x$ and $A_z$ in the range of recoil momenta from 0 to about $300 \mathrm{MeV}/c$. The experimental equipment utilized in these measurements is described, with special attention devoted to the calibration of the hadron spectrometer, BigBite. Results on the measured asymmetries are presented, together with first attempts at their comparison to the state-of-the art Faddeev calculations. The remaining open problems and challenges for future work are also discussed.