Neutron-Induced Scintillation in Organics
(2023)- Abstract
- Neutrons are widely used as probes of matter to study materials in a broad range of fields from physics, chemistry and medicine to material sciences. Any application utilizing neutrons needs to employ a well-understood and optimized neutron-detector system. This thesis is centered on fundamental aspects of neutron-detector development, including the establishment of the Source Testing Facility at Lund University, experimental methods for the in-depth characterization of scintillator-based neutron detectors and analytical and computational methods for the precise interpretation of results. It focuses on the response of liquid organic scintillators to fast-neutron and gamma-ray irradiations, specifically for NE 213A, EJ 305, EJ 331 and EJ... (More)
- Neutrons are widely used as probes of matter to study materials in a broad range of fields from physics, chemistry and medicine to material sciences. Any application utilizing neutrons needs to employ a well-understood and optimized neutron-detector system. This thesis is centered on fundamental aspects of neutron-detector development, including the establishment of the Source Testing Facility at Lund University, experimental methods for the in-depth characterization of scintillator-based neutron detectors and analytical and computational methods for the precise interpretation of results. It focuses on the response of liquid organic scintillators to fast-neutron and gamma-ray irradiations, specifically for NE 213A, EJ 305, EJ 331 and EJ 321P. A simulation-based method for detector calibration was developed which allowed for the use of polyenergetic gamma-ray sources in this low energy-resolution environment. With an actinide/beryllium neutron source and a time-of-flight setup, beams of energy-tagged neutrons were used to study the energy-dependent behaviour of the intrinsic pulse-shape of NE 213A and EJ 305 scintillators. The results demonstrated the advantages of the neutron-tagging method and how the combination of neutron tagging and pulse-shape discrimination can give deeper insight into backgrounds resulting from inelastic neutron scattering. A comprehensive characterization of the neutron scintillation-light yield for NE 213A, EJ 305, EJ 331 and EJ 321P was also performed. It employed the simulation-based calibrations to confirm existing light-yield parametrizations for NE 213A and EJ 305, and resulted in light-yield parametrizations for EJ 331 and EJ 321P extracted for the first time from data. In addition to the development of a simulation-based framework for the study of neutron-induced scintillation in organic scintillators, the methods and results presented in this thesis lay the foundation for future source-based neutron-tagging efforts and scintillator-detector research and development. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/3e489011-85da-4c03-a9da-ec94eca58285
- author
- Mauritzson, Nicholai LU
- supervisor
-
- Kevin Fissum LU
- Hanno Perrey LU
- Francesco Messi LU
- Robert Frost LU
- opponent
-
- Professor Davinson, Thomas, University of Edinburgh, UK
- organization
- publishing date
- 2023-02-20
- type
- Thesis
- publication status
- published
- subject
- keywords
- liquid organic scintillator, oil, time-of-flight, neutron tagging, light yield, simulation, calibration, NE 213A, EJ 305, EJ 331, EJ 321P, Source Testing Facility, pedagogy, Fysicumarkivet A:2023:Mauritzson
- pages
- 178 pages
- publisher
- Lund University , Department of physics
- defense location
- Rydbergsalen, Fysicum. Join via zoom: https://lu-se.zoom.us/j/66961634590?pwd=dTJoLzJYclQ5QjdDTHdDNFZrSlNzQT09 passcode: 214891
- defense date
- 2023-03-31 13:15:00
- ISBN
- 978-91-8039-557-1
- 978-91-8039-556-4
- language
- English
- LU publication?
- yes
- id
- 3e489011-85da-4c03-a9da-ec94eca58285
- date added to LUP
- 2023-02-20 17:34:22
- date last changed
- 2023-05-31 10:12:41
@phdthesis{3e489011-85da-4c03-a9da-ec94eca58285,
abstract = {{Neutrons are widely used as probes of matter to study materials in a broad range of fields from physics, chemistry and medicine to material sciences. Any application utilizing neutrons needs to employ a well-understood and optimized neutron-detector system. This thesis is centered on fundamental aspects of neutron-detector development, including the establishment of the Source Testing Facility at Lund University, experimental methods for the in-depth characterization of scintillator-based neutron detectors and analytical and computational methods for the precise interpretation of results. It focuses on the response of liquid organic scintillators to fast-neutron and gamma-ray irradiations, specifically for NE 213A, EJ 305, EJ 331 and EJ 321P. A simulation-based method for detector calibration was developed which allowed for the use of polyenergetic gamma-ray sources in this low energy-resolution environment. With an actinide/beryllium neutron source and a time-of-flight setup, beams of energy-tagged neutrons were used to study the energy-dependent behaviour of the intrinsic pulse-shape of NE 213A and EJ 305 scintillators. The results demonstrated the advantages of the neutron-tagging method and how the combination of neutron tagging and pulse-shape discrimination can give deeper insight into backgrounds resulting from inelastic neutron scattering. A comprehensive characterization of the neutron scintillation-light yield for NE 213A, EJ 305, EJ 331 and EJ 321P was also performed. It employed the simulation-based calibrations to confirm existing light-yield parametrizations for NE 213A and EJ 305, and resulted in light-yield parametrizations for EJ 331 and EJ 321P extracted for the first time from data. In addition to the development of a simulation-based framework for the study of neutron-induced scintillation in organic scintillators, the methods and results presented in this thesis lay the foundation for future source-based neutron-tagging efforts and scintillator-detector research and development.}},
author = {{Mauritzson, Nicholai}},
isbn = {{978-91-8039-557-1}},
keywords = {{liquid organic scintillator; oil; time-of-flight; neutron tagging; light yield; simulation; calibration; NE 213A; EJ 305; EJ 331; EJ 321P; Source Testing Facility; pedagogy; Fysicumarkivet A:2023:Mauritzson}},
language = {{eng}},
month = {{02}},
publisher = {{Lund University , Department of physics}},
school = {{Lund University}},
title = {{Neutron-Induced Scintillation in Organics}},
url = {{https://lup.lub.lu.se/search/files/138443172/PhD_thesis_Nicholai_Mauritzson.pdf}},
year = {{2023}},
}