Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.547884
Title: Measurement of polarisation observables using linearly polarised photons with the crystal ball at MAMI
Author: Howdle, David A.
ISNI:       0000 0004 2712 7327
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2012
Availability of Full Text:
 Access from EThOS: Access from Institution:
Abstract:
In order to further study and expand the kinematic coverage of polarisation observables in pseudoscalar meson photoproduction, a measurement of polarisation observables has been performed at the MAMI facility in Mainz, Germany. The measurement used a beam of linearly polarised photons using the coherent bremsstrahlung method and the Glasgow Tagged Photon Spectrometer. The photon beam was incident on an $lH_{2}$ target in order to produce the meson photoproduction reaction $\gamma p \to \pi^{0} p$. This target was housed in the centre of the Crystal Ball detector which was used to detect the reaction products. A carbon polarimeter was used to measure the polarisation of the recoiling proton through secondary scattering. The polarisation observables for pseudoscalar meson photoproduction which were measured included: $\Sigma$, the modulation induced in the reaction products by the linearly polarised photon beam; $O_{x}$, the transfer of linear polarisation from the beam to the recoiling proton; and $T$, the polarisation inherent in the target proton. These measurements were performed over a wide kinematic range in both photon energy and polar angle in the centre of mass system, and were compared to three partial wave analyses, SAID, MAID and Bonn-Gatchina. The results contribute to the ongoing search for a complete understanding of the nucleon's excitation spectrum, and significantly enhance the world dataset for these polarisation observables.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.547884  DOI: Not available
Keywords: QC Physics
Share: