CYCLOTRONS2022 - List of Authors (Hutton, T.)

Paper	Title	Page
TUBO01	Measurement of Detector Response Functions for Fast Neutron Spectroscopy with Organic Scintillators	121
	T. Hutton, A. Buffler, E. Jarvie, K. Maibane, N.B. Ndabeni UCT Physics, Cape Town, South Africa
	Spectrum unfolding decouples spectroscopic measurements of neutron fields from accelerator facilities by making use of a well-characterised detector response matrix. Measurements of detector response matrices, derived from time-of-flight, were made at the fast neutron facility at iThemba LABS, South Africa, with neutrons with energies between 10 - 65 MeV for: a traditional BC-501A organic liquid scintillator detector with photomultiplier tube and analogue pulse processing and acquisition; and a modern system comprised of an EJ-276 plastic scintillator, silicon photomultiplier and digital pulse processing and acquisition. The detector response matrices were validated by unfolding neutron energy spectra from measured light output spectra, and compared to the associated energy spectra derived from time-of-flight. Both detector systems demonstrated good agreement between the energy spectra derived from time-of-flight, which is promising for fast neutron spectroscopy with organic scintillators in environments outside of the laboratory.
	Slides TUBO01 [5.487 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-TUBO01
About •	Received ※ 22 December 2022 — Revised ※ 13 February 2023 — Accepted ※ 18 February 2023 — Issue date ※ 12 March 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEBO03	Positron Emitters Produced from Naturally Occurring Targets	183
	T.W. Leadbeater, A. Buffler, T. Hutton, M. van Heerden UCT Physics, Cape Town, South Africa
	Short lived positron emitters are used as flow following tracer particles in the study of dynamic processes within physics and engineering applications. For full representation of the materials of interest, tracer particles must be activated with proton rich radionuclides utilising reactions on their naturally abundant isotopic content. Cyclotron accelerated alpha particle beams incident upon (16O) oxygen rich targets have been investigated in producing the positron emitter 18F within naturally occurring materials. Simulations and numeric calculations of the beam conditions are used to maximise the activation yield and minimise heat load by carefully placing the Bragg peak in relation to the water-cooled target. Corresponding to the target thickness, the 100 MeV extraction energy is degraded to match a broad resonance in 18F production around 35 MeV, while maintaining energy above the 18 MeV threshold. Beam currents below 1 µA resulted in typical 18F yields of 1 - 2 mCi within spherical SiO₂ targets of diameters 1 - 10 mm, ideal for envisaged application studies.
	Slides WEBO03 [4.876 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEBO03
About •	Received ※ 28 December 2022 — Revised ※ 16 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 27 May 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Measurement of Detector Response Functions for Fast Neutron Spectroscopy with Organic Scintillators

121

T. Hutton, A. Buffler, E. Jarvie, K. Maibane, N.B. Ndabeni
UCT Physics, Cape Town, South Africa

Spectrum unfolding decouples spectroscopic measurements of neutron fields from accelerator facilities by making use of a well-characterised detector response matrix. Measurements of detector response matrices, derived from time-of-flight, were made at the fast neutron facility at iThemba LABS, South Africa, with neutrons with energies between 10 - 65 MeV for: a traditional BC-501A organic liquid scintillator detector with photomultiplier tube and analogue pulse processing and acquisition; and a modern system comprised of an EJ-276 plastic scintillator, silicon photomultiplier and digital pulse processing and acquisition. The detector response matrices were validated by unfolding neutron energy spectra from measured light output spectra, and compared to the associated energy spectra derived from time-of-flight. Both detector systems demonstrated good agreement between the energy spectra derived from time-of-flight, which is promising for fast neutron spectroscopy with organic scintillators in environments outside of the laboratory.

Slides TUBO01 [5.487 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-TUBO01

About •

Received ※ 22 December 2022 — Revised ※ 13 February 2023 — Accepted ※ 18 February 2023 — Issue date ※ 12 March 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEBO03

Positron Emitters Produced from Naturally Occurring Targets

183

T.W. Leadbeater, A. Buffler, T. Hutton, M. van Heerden
UCT Physics, Cape Town, South Africa

Short lived positron emitters are used as flow following tracer particles in the study of dynamic processes within physics and engineering applications. For full representation of the materials of interest, tracer particles must be activated with proton rich radionuclides utilising reactions on their naturally abundant isotopic content. Cyclotron accelerated alpha particle beams incident upon (16O) oxygen rich targets have been investigated in producing the positron emitter 18F within naturally occurring materials. Simulations and numeric calculations of the beam conditions are used to maximise the activation yield and minimise heat load by carefully placing the Bragg peak in relation to the water-cooled target. Corresponding to the target thickness, the 100 MeV extraction energy is degraded to match a broad resonance in 18F production around 35 MeV, while maintaining energy above the 18 MeV threshold. Beam currents below 1 µA resulted in typical 18F yields of 1 - 2 mCi within spherical SiO₂ targets of diameters 1 - 10 mm, ideal for envisaged application studies.

Slides WEBO03 [4.876 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEBO03

About •

Received ※ 28 December 2022 — Revised ※ 16 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 27 May 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)