G4 Doctoral dissertation (monograph)
New β-decay half-lives of heavy neutron-rich nuclei and performance studies of the GEM-TPC detector (2023)

Luoma, M. (2023). New β-decay half-lives of heavy neutron-rich nuclei and performance studies of the GEM-TPC detector [Doctoral dissertation]. University of Jyväskylä. JYU dissertations, 710. https://urn.fi/URN:ISBN:978-951-39-9789-2

JYU authors or editors

Publication details

All authors or editors: Luoma, Minna

eISBN: 978-951-39-9789-2

Journal or series: JYU dissertations

eISSN: 2489-9003

Publication year: 2023

Number in series: 710

Number of pages in the book: 1 verkkoaineisto (113 sivua)

Publisher: University of Jyväskylä

Place of Publication: Jyväskylä

Publication country: Finland

Publication language: English

Persistent website address: https://urn.fi/URN:ISBN:978-951-39-9789-2

Publication open access: Openly available

Publication channel open access: Open Access channel

Abstract

This thesis presents results from the experiments aimed to measure new b-decay half-lives of neutron-rich nuclei near the N = 126 shell and investigate the performance of the GEM-TPC detector. Experimental requirements for the b-decay experiment included production, identification, and analysis of properties of heavy neutron-rich nuclei. In total, one experiment and two in-beam tests were conducted at the FAIR/GSI facility. Four new b-decay half-lives for isotopes 197-198Re, 195W, and 191Ta were measured. Additionally, the measured half-life values for 199-200Os and 196Re were consistent with literature values. Detailed analyses of the experiment and in-beam tests are presented, including a comparison with measured b-decay half-lives and predicted values from the FRDM + QRPA and CQRPA models. Consistently shorter half-life values than predictions were observed for nuclei near N = 126 shell. The performance analysis of the GEM-TPC detector provided information on its properties, such as x position resolution, y position resolution, cluster strip multiplicity, control sum, detection and tracking efficiencies, strip signal summation, and data digitization impact. Moreover, a clusterization was utilized for the first time in the data analysis of the GEM-TPC detector. The objectives of the studies were to increase our understanding about the properties of nuclei in the vicinity of the third r-process peak and to measure the capabilities of the GEM-TPC. The experimental results of the new b-decay halflives can be used to validate existing models and improve our understanding of the properties of these nuclei. The performance study of GEM-TPC provides information on its measuring capabilities and suitability for future investigations and assists in planning the future experiments.

Keywords: beta radiation; half life; neutrons; atoms; doctoral dissertations

Free keywords: beta-decay; neutron-rich nuclei; half-life; r-process; GEM-TPC; Super FRS

Contributing organizations

Ministry reporting: Yes

VIRTA submission year: 2023