Award Date


Degree Type


Degree Name

Master of Science (MS)


Mechanical Engineering

First Committee Member

William Culbreth

Number of Pages



The Z Machine at Sandia National Laboratory is a pulsed powered electron accelerator that is able to produce fusion neutrons by pinching the deuterium and tritium gas with the surrounding high temperature plasma. Neutron detectors are placed in various locations throughout the room in order to detect these fusion neutrons. Plastic scintillating neutron detectors are sensitive to other types of unwanted radiations however. The purpose of this project was to design a shield that would allow the fusion neutrons to enter the detector while preventing the other types of unwanted radiation from getting to that same detector. A shield was designed with layers of high Z and low Z material in order to block the radiation that would be incident on the sides of the shield. Combinations of polyethylene, lead, carbon, iron and tungsten were used to maximize the efficiency of the shield. With the lead contributing a large portion of the total weight of the shield finite element analysis was used to ensure the design safe. Results showed that the structure was designed within the structural limits of the steel that was used. Radiation transport results showed that the shield was 1.37 to 459 times better at reducing the amount of unwanted radiation that would be incident on the shield. The range of effectiveness values are angle of incidence and particle type dependant.


Detector; Element; Finite; Laboratory; Modeling; National; New Mexico; Radiation; Sandia; Shield; Transport

Controlled Subject

Nuclear engineering; Mechanical engineering

File Format


File Size

2938.88 KB

Degree Grantor

University of Nevada, Las Vegas




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