+publisher:"University of Guelph" +contributor:("Svensson, Carl")

University of Guelph

1. Dunlop, Ryan. High-Precision Branching Ratio Measurement for the Superallowed β+ Emitter 74Rb.

Degree: MS, Department of Physics, 2012, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3514

► Precision measurements of superallowed Fermi β-decay allow for stringent tests of the magnitude of isospin-symmetry-breaking effects in nuclei, the validity of the conserved vector current… (more)

Subjects/Keywords: Superallowed; beta decay; isospin-symmetry-breaking; Cabibbo-Kobayashi-Maskawa; CKM; conserved-vector-current; CVC; Standard Model; gamma-ray spectroscopy; TRIUMF

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dunlop, R. (2012). High-Precision Branching Ratio Measurement for the Superallowed β+ Emitter 74Rb. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3514

Chicago Manual of Style (16^th Edition):

Dunlop, Ryan. “High-Precision Branching Ratio Measurement for the Superallowed β+ Emitter 74Rb.” 2012. Masters Thesis, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3514.

MLA Handbook (7^th Edition):

Dunlop, Ryan. “High-Precision Branching Ratio Measurement for the Superallowed β+ Emitter 74Rb.” 2012. Web. 10 Apr 2021.

Vancouver:

Dunlop R. High-Precision Branching Ratio Measurement for the Superallowed β+ Emitter 74Rb. [Internet] [Masters thesis]. University of Guelph; 2012. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3514.

Council of Science Editors:

Dunlop R. High-Precision Branching Ratio Measurement for the Superallowed β+ Emitter 74Rb. [Masters Thesis]. University of Guelph; 2012. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3514

University of Guelph

2. Laffoley, Alex. High Precision Half-Life Measurements for the Superallowed Fermi Beta Emitters Oxygen-14 and Neon-18.

Degree: PhD, Department of Physics, 2015, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9284

► The study of superallowed Fermi β transitions between nuclear isobaric analogue states of spin (J,π) = (0,+) provides demanding, and fundamental, tests of the properties… (more)

▼ The study of superallowed Fermi β transitions between nuclear isobaric analogue states of spin (J,π) = (0,+) provides demanding, and fundamental, tests of the properties of the electroweak interaction. These studies, which include some 200+ individual measurements, have been used to test the conserved vector current hypothesis, set limits on weak scalar currents, test the unitarity of the Cabibbo-Kobayashi-Maskawa quark mixing matrix, and set limits on physics beyond the Standard Model. A series of high-precision half-life measurements for the superallowed Fermi β emitters 14O and 18Ne were performed at the Isotope Separator and Accelerator Facility at TRIUMF. For each nucleus, 2 independent high-precision half-life measurements were made resulting in systematic self-consistent tests of the analysis methods. The half-life of 14O was measured simultaneously through both direct β and γ counting techniques using a thin plastic scintillator to detect the β particles and an array of high-purity germanium detectors to detect the characteristic 2312.6~keV γ-ray emitted in >99% of 14O β decays. The results of this analysis yielded a β half-life of 70.610±0.030 s and a γ half-life of 70.632±0.094 s, resulting in a new world-average half-life for 14O of 70.619±0.011 s with a χ-squared per degree of freedom of 0.89. The half-life of 18Ne was measured via direct β counting techniques using a 4π gas proportional counter during two separate experiments with different beam properties and different beam energies. The results of these half-life measurements were 1.66424+0.00072-0.00064 s and 1.66368+0.00084-0.00050 s. These two results are consistent with each other and their average yields a half-life of 1.66400+0.00057-0.00048 s, an improvement in precision by a factor of 2 over the previous world half-life data set for 18Ne. In addition, the half-life of 23Ne was measured as part of an investigation of possible systematic uncertainties associated with the diffusion of neon sample implanted in aluminum tape systems. The new world average 23Ne half-life is 37.148±0.032 s, which represents an improvement in precision by a factor of 1.7 when compared to the world average prior to the measurements performed in this work. The precise half-life measurements for 14O and 18Ne reported here can be combined with the respective branching ratio and Q value measurements for these isotopes in order to determine the ft values for these superallowed Fermi β transitions. Advisors/Committee Members: Svensson, Carl (advisor).

Subjects/Keywords: Beta Decay; Half-Life; Oxygen-14; Neon-18; 14O; 18Ne; Fundamental symmetries

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APA (6^th Edition):

Laffoley, A. (2015). High Precision Half-Life Measurements for the Superallowed Fermi Beta Emitters Oxygen-14 and Neon-18. (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9284

Chicago Manual of Style (16^th Edition):

Laffoley, Alex. “High Precision Half-Life Measurements for the Superallowed Fermi Beta Emitters Oxygen-14 and Neon-18.” 2015. Doctoral Dissertation, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9284.

MLA Handbook (7^th Edition):

Laffoley, Alex. “High Precision Half-Life Measurements for the Superallowed Fermi Beta Emitters Oxygen-14 and Neon-18.” 2015. Web. 10 Apr 2021.

Vancouver:

Laffoley A. High Precision Half-Life Measurements for the Superallowed Fermi Beta Emitters Oxygen-14 and Neon-18. [Internet] [Doctoral dissertation]. University of Guelph; 2015. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9284.

Council of Science Editors:

Laffoley A. High Precision Half-Life Measurements for the Superallowed Fermi Beta Emitters Oxygen-14 and Neon-18. [Doctoral Dissertation]. University of Guelph; 2015. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9284

University of Guelph

3. MacLean, Andrew. Gamma-Gamma Angular Correlation Measurements With GRIFFIN.

Degree: MS, Department of Physics, 2016, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9597

► When an excited nuclear state emits successive γ-rays in a γ − γ cascade, an anisotropy is generally found in the spatial distribution of the… (more)

▼ When an excited nuclear state emits successive γ-rays in a γ − γ cascade, an anisotropy is generally found in the spatial distribution of the second γ-ray, γ2, with respect to the first, γ1. By defining the direction of γ1 to be the z-axis, the intermediate level, in general will have an uneven distribution of m-states. This causes an anisotropy in the angular correlation of the second γ-ray with respect to the first. Angular correlation measurements can be used for the assignment of spins and parities to the nuclear states, and thus provide a powerful means to elucidate the structure of nuclei away from stability through β − γ − γ coincidence measurements. In order to explore the sensitivity of the new 16 high-purity germanium (HPGe) clover-detector Gamma-Ray Infras- tructure For Fundamental Investigations of Nuclei (GRIFFIN) at TRIUMF-ISAC, a series of measurements were taken to establish a methodology for such γ − γ angular correlations. The first case studied to test the performance of GRIFFIN for these measurements was the well-known 4+ → 2+ → 0+ γ−γ cascade from 60Co β− decay. Geant4 simulated experiments and experimental source data were collected and analyzed as the primary test of GRIFFIN. The next case studied was a 66Ga beam implanted in the centre of the array. With 66Ga, three cascades were examined to analyze the γ − γ angular correlations. The first angular correlation being a 2+ →2+ →0+ cascade of 833-1039 keV γ-rays with a known mixing ratio of δ = -1.9(3). Next was a known 0+ →2+ →0+ cascade with the γ-ray energies in coincidence being 1333-1039 keV . The final correlation for this nucleus was a 1+ →2+ →0+ cascade of 2752-1039 keV γ-rays with a mixing ratio of -0.12(2). The next nucleus studied was the β+ decay of 62Ga, which is a superallowed Fermi β emitter. This nucleus was a first attempt to discern a recently challenged spin assignment to the 2.34 MeV excited state. The labelling of this state as a 2+ or a 0+ has effects on the isospin symmetry breaking correction factor used for calculating Ft values. Forthe60Comeasurementsthespinassignmentswerefullyconsistentwitha4+ →2+ →0+ cascade, but due to the similarity of the 2+ →2+ →0+ with a mixing ratio of δ = 0.18(1) which gives a nearly identical angular correlation and was indistinguishable. Also in 66Ga decay, the precision of the mixing ratio for the 2+ →2+ →0+ cascade involving the 833- 1039 keV γ-rays was improved giving a value of δ = −2.1(2). Finally, the mixing ratio for the 1+ →2+ →0+ cascade involving the 2752-1039 keV γ-rays was determined to be δ = −0.08(3). This measurement was completed without realizing the value was known and is in complete agreement with the previous measurement. In the 62Ga measurement the assignment of the spin of the 2.34 MeV excited state was unable to be discerned due to reduced statistics from a faulty extraction electrode. The measurement seemed to favour the assignment as a 0+ state but additional statistics are required for a definitive assignment. Advisors/Committee Members: Svensson, Carl (advisor).

Subjects/Keywords: Nuclear Physics; gamma decay; GRIFFIN; angular correlartions

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

MacLean, A. (2016). Gamma-Gamma Angular Correlation Measurements With GRIFFIN. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9597

Chicago Manual of Style (16^th Edition):

MacLean, Andrew. “Gamma-Gamma Angular Correlation Measurements With GRIFFIN.” 2016. Masters Thesis, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9597.

MLA Handbook (7^th Edition):

MacLean, Andrew. “Gamma-Gamma Angular Correlation Measurements With GRIFFIN.” 2016. Web. 10 Apr 2021.

Vancouver:

MacLean A. Gamma-Gamma Angular Correlation Measurements With GRIFFIN. [Internet] [Masters thesis]. University of Guelph; 2016. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9597.

Council of Science Editors:

MacLean A. Gamma-Gamma Angular Correlation Measurements With GRIFFIN. [Masters Thesis]. University of Guelph; 2016. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9597

University of Guelph

4. Dunlop, Michelle. High-Precision Half-Life Measurements for the Superallowed Beta+ Emitters 10C and 22Mg.

Degree: PhD, Department of Physics, 2018, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14154

► High precision measurements of the ft values for superallowed Fermi β transitions be- tween Jπ = 0+, T = 1 isobaric analogue states allow for… (more)

▼ High precision measurements of the ft values for superallowed Fermi β transitions be- tween Jπ = 0+, T = 1 isobaric analogue states allow for stringent tests of the electroweak interaction described by the Standard Model. These transitions provide an experimental probe of the Conserved-Vector-Current hypothesis, the most precise determination of Vud, the up- down element of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix, and set stringent limits on the existence of scalar currents in the weak interaction. This thesis focuses on high-precision half-life measurements of two superallowed Fermi β+ emitters, 10C and 22Mg. These half-life measurements were performed at TRIUMF’s Isotope Separator and Accelerator facility. For both cases, measurements of their half-lives were motivated by the discrepancies between previous measurements found in literature that resulted in inflations in the uncertainties to account for the inconsistent measurements. Two independent measurements of the 10C half-life were performed. The first measurement was performed via γ-ray photopeak counting using the 8π γ-ray spectrometer, an array of 20 Compton-suppressed high-purity germanium detectors, by measuring the time profile of the characteristic 718-keV γ-ray. This analysis yielded T1/2 = 19.2969 ± 0.0072 s. A second measurement was performed via direct β counting, using a 4π continuous-flow gas proportional β counter. The results from this analysis yields T1/2 = 19.3009 ± 0.0017 s, and is the most precise superallowed half-life measurement reported to date and the first to ever achieve a relative precision below 10−4. A half-life measurement of the superallowed β+ emitter 22Mg was performed via direct β counting using the 4π continuous-flow gas proportional counter. This analysis yielded a half-life of T1/2 = 3.87400 ± 0.0079 s. This measurement resolved a discrepancy between the previous world-average dataset, which was composed of only two measurements. These two half-life measurements showed a disagreement characterized by a χ2/ν = 4.0, however, upon the inclusion of the new measurement presented in this thesis, now has a χ2/ν = 1.1. The high-precision half-life measurements reported in this thesis, once included with the other high-precision superallowed data, can be used to test fundamental properties of the Standard Model. In particular, the improved uncertainty of the 10C half-life can be used to provide a more stringent limit on the contribution of scalar currents in the Standard Model. The improvement in the uncertainty of the 22Mg half-life provides further tests of the isospin symmetry breaking corrections in superallowed Fermi β decays. Advisors/Committee Members: Svensson, Carl (advisor).

Subjects/Keywords: Nuclear Physics; Superallowed Beta Decay; Half-Life; Beta Decay

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APA (6^th Edition):

Dunlop, M. (2018). High-Precision Half-Life Measurements for the Superallowed Beta+ Emitters 10C and 22Mg. (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14154

Chicago Manual of Style (16^th Edition):

Dunlop, Michelle. “High-Precision Half-Life Measurements for the Superallowed Beta+ Emitters 10C and 22Mg.” 2018. Doctoral Dissertation, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14154.

MLA Handbook (7^th Edition):

Dunlop, Michelle. “High-Precision Half-Life Measurements for the Superallowed Beta+ Emitters 10C and 22Mg.” 2018. Web. 10 Apr 2021.

Vancouver:

Dunlop M. High-Precision Half-Life Measurements for the Superallowed Beta+ Emitters 10C and 22Mg. [Internet] [Doctoral dissertation]. University of Guelph; 2018. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14154.

Council of Science Editors:

Dunlop M. High-Precision Half-Life Measurements for the Superallowed Beta+ Emitters 10C and 22Mg. [Doctoral Dissertation]. University of Guelph; 2018. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14154

University of Guelph

5. Dunlop, Ryan. Beta and beta-delayed neutron decay of the N = 82 nuclei 128-130Cd and 131In studied with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN).

Degree: PhD, Department of Physics, 2019, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/16278

► Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei (GRIFFIN) is a new high-efficiency γ-ray spectrometer designed for use in decay spectroscopy experiments with low-energy radioactive ion… (more)

▼ Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei (GRIFFIN) is a new high-efficiency γ-ray spectrometer designed for use in decay spectroscopy experiments with low-energy radioactive ion beams provided by TRIUMF's Isotope Separator and Accelerator (ISAC-I) facility. The high-efficiency GRIFFIN array comprises 16 Compton-suppressed large-volume HPGe clovers, and is designed to be used with a suite of ancillary detectors, providing a powerful and versatile tool for studying exotic nuclei. The structures of N = 82 nuclei below doubly-magic ¹³²Sn are crucial for calculations of the astrophysical r-process as these isotopes form `waiting-points' that play an important role in the formation and shape of the second r-process abundance peak. Many of the most neutron-rich N = 82 nuclei are, however, out of reach to the current generation of radioactive beam facilities and their properties must be predicted. In the past, shell-model calculations for the half-lives of these nuclei have been performed by adjusting the quenching of the Gamow-Teller (GT) operator in order to reproduce the half-life of ¹³⁰Cd. However, the calculated half-lives of the nuclei below ¹³⁰Cd are known to be systematically too large. A recent measurement of the ¹³⁰Cd half-life with EURICA indicated a shorter half-life of ¹³⁰Cd, which would lead to a re-scaling of the GT quenching by a constant factor for all nuclei in the region and potentially resolves the discrepancy. However, the reduced quenching of the GT operator implied by these results creates a new discrepancy in the calculated half-life of the N=82 isotope ¹³¹In. Half-life measurements of nuclei in this region are complicated due to the presence of β-decaying isomers with comparable half-lives and large β n branches, making γ-ray photo-peak gating with a high-resolution, high-efficiency, γ-ray spectrometer an ideal method to measure each of the isomeric half-lives. In this work, measurements of the half-lives of the ^128-130Cd isotopes were performed. The half-life of the N=82 r-process waiting point nucleus ¹³⁰Cd was measured to be 126(4)~ms confirming the EURICA measurements and in strong disagreement with the earlier measurements of 162(7)~ms and 195(35)~ms. A detailed data set for the β and β n decay of ¹³¹In was also analyzed. The β decay from the single proton hole nucleus ¹³¹In to the single neutron hole nucleus ¹³¹Sn is of current interest with respect to advancing our understanding of nuclear forces and shell evolution in this region, including modelling the astrophysical r-process. In this work, three different β decaying states in ¹³¹In were studied in detail, providing new information about the shell structure of ¹³¹Sn. The half-lives of these three β decaying states of ¹³¹In measured in this work agree with the previous measurements. The half-life of each β decaying state of ¹³¹In is significantly longer… Advisors/Committee Members: Svensson, Carl (advisor).

Subjects/Keywords: Nuclear; Nuclear Astrophysics; r-process; beta decay

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APA (6^th Edition):

Dunlop, R. (2019). Beta and beta-delayed neutron decay of the N = 82 nuclei 128-130Cd and 131In studied with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN). (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/16278

Chicago Manual of Style (16^th Edition):

Dunlop, Ryan. “Beta and beta-delayed neutron decay of the N = 82 nuclei 128-130Cd and 131In studied with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN).” 2019. Doctoral Dissertation, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/16278.

MLA Handbook (7^th Edition):

Dunlop, Ryan. “Beta and beta-delayed neutron decay of the N = 82 nuclei 128-130Cd and 131In studied with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN).” 2019. Web. 10 Apr 2021.

Vancouver:

Dunlop R. Beta and beta-delayed neutron decay of the N = 82 nuclei 128-130Cd and 131In studied with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN). [Internet] [Doctoral dissertation]. University of Guelph; 2019. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/16278.

Council of Science Editors:

Dunlop R. Beta and beta-delayed neutron decay of the N = 82 nuclei 128-130Cd and 131In studied with the Gamma-Ray Infrastructure for Fundamental Investigations of Nuclei (GRIFFIN). [Doctoral Dissertation]. University of Guelph; 2019. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/16278

University of Guelph

6. Coleman, Robin. Beta Decay of Neutron-Rich 52K.

Degree: MS, Department of Physics, 2020, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17744

► Nuclei away from the line of β stability have been found to demonstrate behavior that is inconsistent with the traditional magic numbers of the spherical… (more)

Subjects/Keywords: Nuclear Structure; Shell Model; Beta Decay; Potassium; Calcium; Scandium; Magic Numbers

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APA (6^th Edition):

Coleman, R. (2020). Beta Decay of Neutron-Rich 52K. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17744

Chicago Manual of Style (16^th Edition):

Coleman, Robin. “Beta Decay of Neutron-Rich 52K.” 2020. Masters Thesis, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17744.

MLA Handbook (7^th Edition):

Coleman, Robin. “Beta Decay of Neutron-Rich 52K.” 2020. Web. 10 Apr 2021.

Vancouver:

Coleman R. Beta Decay of Neutron-Rich 52K. [Internet] [Masters thesis]. University of Guelph; 2020. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17744.

Council of Science Editors:

Coleman R. Beta Decay of Neutron-Rich 52K. [Masters Thesis]. University of Guelph; 2020. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/17744

University of Guelph

7. Rand, Evan Thomas. Investigation of the E2 and E3 matrix elements in 200Hg using direct nuclear reactions.

Degree: PhD, Department of Physics, 2015, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9416

► A nuclear-structure campaign has been initiated to investigate the isotopes of Hg around mass 199. To date, 199Hg provides the most stringent limit on an… (more)

▼ A nuclear-structure campaign has been initiated to investigate the isotopes of Hg around mass 199. To date, 199Hg provides the most stringent limit on an atomic electric dipole moment (EDM). Standard Model predictions of the EDM in 199Hg are many orders of magnitude below current experimental reach. There are, however, many models beyond the Standard Model, such as multiple-Higgs theories and supersymmetry, that generally predict much larger EDMs within experimental reach. The observation of a large permanent EDM would represent a clear signal of CP violation from new physics outside the Standard Model. Theoretical nuclear-structure calculations for 199Hg are challenging, and give varied predictions for the excited-state spectrum. Understanding the E2 and E3 strengths in 199Hg will make it possible to develop a nuclear-structure model for the Schiff strength based on these matrix elements, and thereby constrain present models that predict the contribution of octupole collectivity to the Schiff moment of the nucleus. One of the most direct ways of measuring the matrix elements connecting the ground state to excited states is through inelastic hadron scattering. The high level density of a heavy odd-A nucleus like 199Hg makes a measurement extremely challenging. Complementary information can, however, be determined for states in the neighbouring even-even isotopes of 198Hg and 200Hg, and single-nucleon transfer reactions on targets of even-even isotopes of Hg can yield important information on the single-particle nature of 199Hg. The work presented here is the result of two experiments which used a 22-MeV deuteron beam incident on an isotopically enriched target of 200Hg32S. These experiments were performed using the Q3D magnetic spectrograph at the Maier-Leibnitz Laboratory, in Garching, Germany. The first experiment was an inelastic deuteron scattering experiment, 200Hg(d,d’)200Hg, populating 97 states up to an excitation energy of 4.2 MeV. Fifty-four states were newly discovered. Deformation parameters were extracted through coupled-channel calculations with global optical-model potential (OMP) parameter sets. The total B(E3; 0+ to 3-) strength in this region was estimated to be 0.55+0.12-0.18 e2b3, where the reported errors represent the upper and lower limits. The second experiment was a single-nucleon transfer reaction into 199Hg, 200Hg(d,t)199Hg, up to an excitation energy of 3 MeV. In total, 91 excited levels were identified, including fifty newly observed levels in this work. Spin-parity assignments and spectroscopic factors were extracted through distorted-wave Born approximation calculations with global OMP sets. The results from these two experiments are presented and further discussed in this thesis. Advisors/Committee Members: Garrett, Paul (advisor), Svensson, Carl (advisor).

Subjects/Keywords: direct nuclear reactions; deuteron inelastic scattering; (d,t) pickup reaction; 199Hg; 200Hg; electric dipole moment; Schiff moment; DWBA; Coupled-channel calculations

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rand, E. T. (2015). Investigation of the E2 and E3 matrix elements in 200Hg using direct nuclear reactions. (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9416

Chicago Manual of Style (16^th Edition):

Rand, Evan Thomas. “Investigation of the E2 and E3 matrix elements in 200Hg using direct nuclear reactions.” 2015. Doctoral Dissertation, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9416.

MLA Handbook (7^th Edition):

Rand, Evan Thomas. “Investigation of the E2 and E3 matrix elements in 200Hg using direct nuclear reactions.” 2015. Web. 10 Apr 2021.

Vancouver:

Rand ET. Investigation of the E2 and E3 matrix elements in 200Hg using direct nuclear reactions. [Internet] [Doctoral dissertation]. University of Guelph; 2015. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9416.

Council of Science Editors:

Rand ET. Investigation of the E2 and E3 matrix elements in 200Hg using direct nuclear reactions. [Doctoral Dissertation]. University of Guelph; 2015. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/9416

8. Finlay, Paul. High-Precision Half-Life and Branching-Ratio Measurements for the Superallowed Beta+ Emitter 26Alm.

Degree: PhD, Department of Physics, 2012, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3510

► High-precision half-life and branching-ratio measurements for the superallowed beta+ emitter 26Alm were performed at the TRIUMF-ISAC radioactive ion beam facility located in Vancouver, Canada. The… (more)

▼ High-precision half-life and branching-ratio measurements for the superallowed beta+ emitter 26Alm were performed at the TRIUMF-ISAC radioactive ion beam facility located in Vancouver, Canada. The branching ratio measurement was performed with the 8pi Spectrometer, an array of 20 high-purity germanium detectors, in conjunction with SCEPTAR, a plastic scintillator array used to detect the emitted beta particles. An upper limit of <= 12 ppm at 90% confidence level was found for the second forbidden beta + decay of 26Alm to the first 2+ state at 1809 keV in 26Mg. An inclusive upper limit of <= 15 ppm at 90% confidence level was found when considering all possible non-analogue beta +/EC decay branches of 26Alm, resulting in a superallowed branching ratio of 100.0000+0−0.0015%. The half-life measurement was performed using a 4pi continuous-flow gas proportional counter and fast tape transport system. The resulting value for the 26Alm half-life, T1/2 = 6.34654(76) s, is consistent with, but 2.5 times more precise than, the previous world average, and represents the single most precisely measured half-life of any superallowed emitting nucleus to date. Combining these results with world-average Q-value measurements yields a superallowed beta -decay ft value of 3037.58(60) s, the most precisely determined ft value for any superallowed emitting nucleus to date. Combined with the small, and precisely quoted, theoretical isospin-symmetry-breaking corrections for this nucleus, the corrected Ft value for 26Alm of 3073.1(12) s is also the most precisely determined for any superallowed emitter by nearly a factor of two and now rivals the precision of all the other 12 precisely measured superallowed beta decays combined. The high-precision experimental ft value for 26Alm superallowed decay reported here provides a new benchmark to refine theoretical models of isospin-symmetry-breaking effects in superallowed Fermi beta decays. Advisors/Committee Members: Svensson, Carl (advisor).

Subjects/Keywords: Nuclear physics; standard model; superallowed beta decay; aluminum; half-life; branching ratio

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APA (6^th Edition):

Finlay, P. (2012). High-Precision Half-Life and Branching-Ratio Measurements for the Superallowed Beta+ Emitter 26Alm. (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3510

Chicago Manual of Style (16^th Edition):

Finlay, Paul. “High-Precision Half-Life and Branching-Ratio Measurements for the Superallowed Beta+ Emitter 26Alm.” 2012. Doctoral Dissertation, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3510.

MLA Handbook (7^th Edition):

Finlay, Paul. “High-Precision Half-Life and Branching-Ratio Measurements for the Superallowed Beta+ Emitter 26Alm.” 2012. Web. 10 Apr 2021.

Vancouver:

Finlay P. High-Precision Half-Life and Branching-Ratio Measurements for the Superallowed Beta+ Emitter 26Alm. [Internet] [Doctoral dissertation]. University of Guelph; 2012. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3510.

Council of Science Editors:

Finlay P. High-Precision Half-Life and Branching-Ratio Measurements for the Superallowed Beta+ Emitter 26Alm. [Doctoral Dissertation]. University of Guelph; 2012. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/3510

9. Zidar, Tammy. Beta decay of neutron-rich 33Mg.

Degree: MS, Department of Physics, 2019, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14706

► The beta-decay and beta-delayed neutron decay of a radioactive 33Mg beam provided by TRIUMF are presented in this thesis. Interest in the beta-decay daughter, 33Al… (more)

Subjects/Keywords: beta decay; nuclear structure

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zidar, T. (2019). Beta decay of neutron-rich 33Mg. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14706

Chicago Manual of Style (16^th Edition):

Zidar, Tammy. “Beta decay of neutron-rich 33Mg.” 2019. Masters Thesis, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14706.

MLA Handbook (7^th Edition):

Zidar, Tammy. “Beta decay of neutron-rich 33Mg.” 2019. Web. 10 Apr 2021.

Vancouver:

Zidar T. Beta decay of neutron-rich 33Mg. [Internet] [Masters thesis]. University of Guelph; 2019. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14706.

Council of Science Editors:

Zidar T. Beta decay of neutron-rich 33Mg. [Masters Thesis]. University of Guelph; 2019. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14706

10. Leach, Kyle G. Neutron Transfer Reactions on 64Zn as a Probe for Testing Shell-Model Isospin-Symmetry-Breaking Theory.

Degree: PhD, Department of Physics, 2012, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/4866

► As part of an ongoing program to study fundamental symmetries in nuclear physics, a thorough investigation into shell-model isospin-symmetry-breaking (ISB) calculation theory has been conducted… (more)

▼ As part of an ongoing program to study fundamental symmetries in nuclear physics, a thorough investigation into shell-model isospin-symmetry-breaking (ISB) calculation theory has been conducted using direct reactions to observe detailed nuclear-structure information. The work presented in this Thesis focuses on the 62Ga superallowed beta-decay system, and consists of two primary experiments; 1) A 64Zn(d,t)63Zn single-neutron transfer reaction, aimed at observing spectroscopic strengths to help guide calculation model-space truncations for the beta-decay wave function radial-overlap component of ISB, and 2) A two-neutron 64Zn(p,t)62Zn transfer to search for excited 0+ states in the daughter nucleus of 62Ga. The experiments were performed at the Maier-Leibnitz-Laboratory, on the joint campuses of the Ludwig-Maximilians Universitat and the Technische Universitat Munchen, in Garching, Germany. In total, 162 states in 63Zn were populated from the 64Zn(d,t) reaction, up to an excitation energy of 4.8 MeV, including the observation of 125 new levels, and unique spin/parity assignments for 92 states. As a result, this work provides the most complete picture for low-spin states in 63Zn to date. A comparison of the extracted S values to the predicted shell-model spectroscopic factors shows an overall over-prediction of strength for the 2p3/2 orbital, and a large disagreement for the 1f7/2 orbital above ~3.5 MeV. No significant 1g9/2 strength was observed, leading to the conclusion that the importance of the 1g9/2 orbital for ISB is small. Additionally, 67 states were observed in 62Zn using the two-neutron pickup mechanism, including the observation of five 0+ states. More than 99% of the total 0+ (p,t) cross-section is observed in the ground-state reaction channel, implying a nearly maximal overlap of the wave functions with the two-nucleon transfer operator. The dominance of the ground-state-to-ground-state (p,t) cross section is strikingly similar to the dominance of the superallowed Fermi beta-decay between isobaric-analogue 0+ states. This suggests that the population of excited 0+ states in the (p,t) reaction may reflect the population in the Fermi decay process, and can be used to guide future experimental and theoretical work. Further discussion of these results as they relate to the ISB correction calculations, and the implications for future theoretical work are presented in this Thesis. Advisors/Committee Members: Garrett, Paul (advisor), Svensson, Carl (advisor).

Subjects/Keywords: Nuclear Physics; Superallowed beta Decay; Isospin Symmetry Breaking; Fundamental Symmetry; Zinc Nuclear Structure; Shell-Model; Neutron Transfer Reaction

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Leach, K. G. (2012). Neutron Transfer Reactions on 64Zn as a Probe for Testing Shell-Model Isospin-Symmetry-Breaking Theory. (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/4866

Chicago Manual of Style (16^th Edition):

Leach, Kyle G. “Neutron Transfer Reactions on 64Zn as a Probe for Testing Shell-Model Isospin-Symmetry-Breaking Theory.” 2012. Doctoral Dissertation, University of Guelph. Accessed April 10, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/4866.

MLA Handbook (7^th Edition):

Leach, Kyle G. “Neutron Transfer Reactions on 64Zn as a Probe for Testing Shell-Model Isospin-Symmetry-Breaking Theory.” 2012. Web. 10 Apr 2021.

Vancouver:

Leach KG. Neutron Transfer Reactions on 64Zn as a Probe for Testing Shell-Model Isospin-Symmetry-Breaking Theory. [Internet] [Doctoral dissertation]. University of Guelph; 2012. [cited 2021 Apr 10]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/4866.

Council of Science Editors:

Leach KG. Neutron Transfer Reactions on 64Zn as a Probe for Testing Shell-Model Isospin-Symmetry-Breaking Theory. [Doctoral Dissertation]. University of Guelph; 2012. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/4866

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