The SPEDE electron spectrometer



O'Neill, GG
(2016) The SPEDE electron spectrometer. PhD thesis, University of Liverpool.

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Abstract

This thesis presents SPEDE (SPectrometer for Electron DEtection) and documents its construction, testing and performance during commissioning at Jyv ̈askyl ̈a, Finland, before deployment at the HIE-ISOLDE facility at CERN coupled with the MINIBALL array to perform in-beam electron-gamma spectroscopy using post-accelerated radioactive ion beams. Results from the Coulomb excitation of 221Rn in 2012 are presented as an example of the need for the construction of a device like SPEDE. In-beam testing and initial commissioning experiments with stable beams took place in four stints during November, February, and May 2015, coupled with detectors from JUROGAMII. This spectrometer will help aid in fully understanding exotic regions of the nuclear chart such as regions with a high degree of octupole deformation, and in those nuclei exhibiting shape coexistence. For the first time, electron spectroscopy has been performed at the target position from states populated in accelerated nuclei via Coulomb excitation. The FWHM of SPEDE is approximately 7 keV at 320 keV, and Doppler correction was possible to improve Doppler broadened peaks to a resolution of 8.9 keV at a peak position of 186 and 196 keV. The results are intended to give the reader a full understanding of the detector and electronics, as well as the performance, capabilities, and usefulness of the spectrometer, both in simulated and in real-world situations.

Item Type: Thesis (PhD)
Divisions: Faculty of Science and Engineering > School of Physical Sciences
Depositing User: Symplectic Admin
Date Deposited: 19 Dec 2016 10:53
Last Modified: 19 Jan 2023 07:25
DOI: 10.17638/03004447
Supervisors:
  • Butler, PA
URI: https://livrepository.liverpool.ac.uk/id/eprint/3004447