Construction and testing of a neutron and gamma spectrometry system using pulse shape discrimination with an organic scintillator. Master's thesis

Technical Report · Mon Mar 01 04:00:00 EST 1993

OSTI ID:6393233

Pope, R S

The goal of this thesis was to construct and test a neutron detector to measure the energy spectrum of 1 to 14-MeV neutrons in the presence of gammas. A spectrometer based on the process of pulse shape discrimination (PSD) was constructed, in which the scintillator NE-213 was used. The primary neutron/gamma sources used were 78-mCi and 4.7-Ci (239)PuBe sources, while 4.7-micro-Ci and 97.6-micro-Ci (22)Na gamma sources were used for energy calibration and additional testing of the detector. Proton recoil spectra and Compton electron spectra were unfolded with the neutron and gamma unfolding code FORIST to generate the incident neutron and gamma spectra, respectively. FORIST, which was written for a CDC computer, was modified to run on a VAX 6420. The experimental spectra were compared to those in the literature. The locations of the peaks in the (239)PuBe spectrum agreed with the literature to within 8.3%, the (239)PuBe gamma spectrum agreed to within 0.7%, while the (22)Na gamma spectrum agreed exactly. Uncertainties in the detection system and unfolding procedure are on the order of 5-10%. This thesis is intended to be a summary of the relevant literature and a user's guide to the PSD spectrometer.... Neutron unfolding code, Gamma spectrometry, Neutron spectrometry, Pulse shape discrimination.

• Research Organization: Air Force Inst. of Tech., Wright-Patterson AFB, OH (United States). School of Engineering
• OSTI ID: 6393233
• Report Number(s): AD-A-262550/7/XAB; AFIT/GNE/ENP--93M-6
• Country of Publication: United States
• Language: English

Related Subjects

440103* -- Radiation Instrumentation-- Nuclear Spectroscopic Instrumentation
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALKALI METAL ISOTOPES
ALKALINE EARTH METALS
ALPHA DECAY RADIOISOTOPES
BENCH-SCALE EXPERIMENTS
BERYLLIUM
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CALIBRATION
CDC COMPUTERS
COMPUTER CODES
COMPUTERS
DATA COVARIANCES
DEC COMPUTERS
DISCRIMINATORS
ELECTRON SPECTRA
ELECTRONIC CIRCUITS
ELEMENTS
ENERGY RANGE
EVEN-ODD NUCLEI
F CODES
GAMMA SOURCES
GAMMA SPECTRA
GAMMA SPECTROMETERS
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LIGHT NUCLEI
MEASURING INSTRUMENTS
METALS
MEV RANGE
MEV RANGE 01-10
NANOSEC LIVING RADIOISOTOPES
NEUTRON DETECTORS
NEUTRON SOURCES
NEUTRON SPECTROMETERS
NUCLEI
ODD-ODD NUCLEI
PARTICLE SOURCES
PERFORMANCE TESTING
PLUTONIUM 239
PLUTONIUM ISOTOPES
PULSE CIRCUITS
PULSE DISCRIMINATORS
RADIATION DETECTORS
RADIATION SOURCES
RADIOISOTOPES
SODIUM 22
SODIUM ISOTOPES
SPECTRA
SPECTROMETERS
SPONTANEOUS FISSION RADIOISOTOPES
TESTING
YEARS LIVING RADIOISOTOPES