First Study of Three-body Photodisintegration of 3He with Double Polarizations at HIGS

Loading...
Thumbnail Image

Date

2010

Journal Title

Journal ISSN

Volume Title

Repository Usage Stats

370
views
287
downloads

Abstract

This dissertation describes the first study of three-body photodisintegration of polarized 3He (γ3He → npp) with a circularly polarized photon beam.

This measurement was carried out at the High Intensity γ-Ray Source(HIγS) facility located at Duke University Free Electron Laser Laboratory and the incoming photon energy was 11.4 MeV. A high-pressure polarized 3He target based on spin exchange optical pumping (SEOP) of hybrid alkali was employed. Two methods--Nuclear Magnetic Resonance (NMR) and Electron

Paramagnetic Resonance (EPR)--were used to measure the polarization, which was determined to be ∼ 42%.

The data from the experiment were analyzed and a GEANT4 simulation was carried out to determine the corrections for finite geometry, neutron multiple scattering and detector efficiencies used in this experiment. The results are compared to the state-of-the-art three-body calculations and agreements are observed within rather large statistical uncertainties of the measurement. This experiment represents the first measurement of the asymmetry using spin-dependent 3He photodisintegration.

The unpolarized differential cross section and helicity-dependent differential cross-section difference results are also presented and compared to the same theoretical calculations followed by a discussion of the results. Total cross section is also extracted using two different methods and agrees well with the theoretical prediction.

New developments including a Sol-Gel coated pyrex 3He cell since the experiment are then presented. The in-beam test results of the aforementioned target cell from May 2009 test run are included and the prospect of future three-body photodisintegration is discussed in the end.

Department

Description

Provenance

Citation

Citation

Zong, Xing (2010). First Study of Three-body Photodisintegration of 3He with Double Polarizations at HIGS. Dissertation, Duke University. Retrieved from https://hdl.handle.net/10161/2416.

Collections


Dukes student scholarship is made available to the public using a Creative Commons Attribution / Non-commercial / No derivative (CC-BY-NC-ND) license.