Neutron-Flux Spectral Determination by Foil Activation

The thermal column at the TRIGA PUSPATI (RTP) research reactor can produce thermal neutron. However, the optimization on the thermal neutron flux produced should be performed to gain a sufficient thermal neutron for boron neutron capture therapy purpose. Thus, the objective of this review is to optimize the thermal neutron flux by designing the collimator with different materials at the thermal column. In order to fulfil the requirement, set by the IAEA standard, the study of Boron Neutron Capture Therapy (BNCT) around the world was being reviewed to study the suitable measurement, material, design, and modification for BNCT at the thermal column of TRIGA MARK-II, Malaysia. Initially, the BNCT mechanisms and history was review. Then, this paper review on the design and modifications for BNCT purpose around the world. Based on this review, suitable material and design can be used for the BNCT in Malaysia. Moreover, this paper also reviews the current status of BNCT at the RTP with the measurement of the thermal neutron flux was conducted along the thermal column at 250 kW. The thermal column of RTP was divided into 3 phases (Phase 1, Phase 2 and Phase 3) so that an accurate measurement can be obtained by using gold foil activation method. This value was used as a benchmark for the neutron flux produced from the thermal column. The reviewed demonstrated that the final thermal neutron flux produced was significantly for BNCT purpose.

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Determination of the Thermal Neutron Flux by Measuring Gamma Radiations with High and Low Resolution Detectors

Journal of Nuclear Physics Material Sciences Radiation and Applications ◽

10.15415/jnp.2019.62027 ◽

2019 ◽

Vol 6 (2) ◽

pp. 187-193

Author(s):

M. M. Hosamani ◽

A. S. Bennal ◽

N. M. Badiger

Keyword(s):

Neutron Flux ◽

Thermal Neutron ◽

Thermal Neutron Flux ◽

High Energy ◽

High Energy Resolution ◽

Indium Foil ◽

Hpge Detectors ◽

Foil Activation ◽

Gamma Radiations

Thermal neutron flux (Фth) of Americium-Beryllium (Am-Be) neutron source has been measured by adopting the foil activation method. The neutrons emitted from Am-Be source are used to activate the indium-115 (115In) foil. The gamma radiations emitted from the activated isomer 116m1In are measured with NaI(Tl) and HPGe detectors. The thermal neutron flux is measured by adopting the cadmium (Cd) foil difference technique in which the Cd foil placed in front of the source to prevent the thermal neutrons from entering into the indium foil. The neutron flux is determined by measuring the gamma radiation emitted from indium foil using a low and high energy resolution NaI(Tl) and HPGe detectors respectively. The measured thermal neutron flux obtained from both detectors has been compared and found that the Фth does not depend on the resolution and type of the detectors used in the present investigations.

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Neutron Beam Characterization at Neutron Radiography (NRAD) Reactor East Beam Following Reactor Modifications

Quantum Beam Science ◽

10.3390/qubs5020008 ◽

2021 ◽

Vol 5 (2) ◽

pp. 8

Author(s):

Sam H. Giegel ◽

Aaron E. Craft ◽

Glen C. Papaioannou ◽

Andrew T. Smolinski ◽

Chad L. Pope

Keyword(s):

Energy Spectrum ◽

Neutron Flux ◽

Neutron Beam ◽

Neutron Energy ◽

Neutron Radiography ◽

Neutron Energy Spectrum ◽

Neutron Beams ◽

Cadmium Ratio ◽

Foil Activation

The Neutron Radiography Reactor at Idaho National Laboratory (INL) has two beamlines extending radially outward from the east and north faces of the reactor core. The control rod withdrawal procedure has recently been altered, potentially changing power distribution of the reactor and thus the properties of the neutron beams, calling for characterization of the neutron beams. The characterization of the East Radiography Station involved experiments used to measure the following characteristics: Neutron flux, neutron beam uniformity, cadmium ratio, image quality, and the neutron energy spectrum. The ERS is a Category-I neutron radiography facility signifying it has the highest possible rank a radiography station can achieve. The thermal equivalent neutron flux was measured using gold foil activation and determined to be 9.61 × 106 ± 2.47 × 105 n/cm2-s with a relatively uniform profile across the image plane. The cadmium ratio measurement was performed using bare and cadmium-covered gold foils and measured to be 2.05 ± 2.9%, indicating large epithermal and fast neutron content in the beam. The neutron energy spectrum was measured using foil activation coupled with unfolding algorithms provided by the software package Unfolding with MAXED and GRAVEL (UMG). The Monte-Carlo N-Particle (MCNP6) transport code was used to assist with the unfolding process. UMG, MCNP6, and measured foil activities were used to determine a neutron energy spectrum which was implemented into the MCNP6 model of the east neutron beam to contribute to future studies.

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