04/21/2021
By Mark Tries

The Radiological Sciences Program in the Department of Physics and Applied Physics invites you to attend an M.S. thesis defense by Noureen Rehman entitled, “A Study of Gamma Radiation Transmission and Buildup for a Tungsten and Silicon Carbide Metal Matrix Composite using the EGSnrc Code”.

M.S. Candidate: Noureen Rehman
Date: April 27, 2021
Time: 12:30 to 2:30 p.m.
Location: This will be a virtual defense via Zoom. Those interested in attending should contact Noureen_Rehman@student.uml.edu and committee chair Mark_Tries@uml.edu at least 24 hours prior to the defense to request access to the meeting.

Committee Chair: Mark Tries, Ph.D., Associate Professor, Department of Physics and Applied Physics, UMass Lowell

Committee Members:

  • Steven Snay, Ph.D., Adjunct Professor, Department of Physics and Applied Physics, UMass Lowell
  • Erin Bertelsen, Ph.D., Assistant Professor, Department of Physics and Applied Physics, UMass Lowell

Abstract:
In the present study, linear attenuation coefficients, mass attenuation coefficients, and air-kerma buildup factors were determined for different compositions of a metal matrix composite consisting of tungsten (W) reinforced with silicon carbide (SiC) using the EGSnrc code. These composite materials were modelled as shields of finite thickness in the EGSnrc simulations, inserted between a photon source and an air-filled detector. Similar determinations were made for lead as a benchmark material. The attenuation coefficients were determined for five compositions of W-SiC and for lead over the photon energy range of 10 keV to 15 MeV. The results for lead are in good agreement with reference values. The air-kerma buildup factors were determined for two of the compositions of W-SiC and for lead over the photon energy range of 1 to 10 MeV. The buildup factors for lead deviated from reference values due to the finite geometry.

All interested persons are welcome to attend.