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Shielding Design and Dose Assessment for an Accelerator-Based BNCT Facility

  • W. B. Howard
  • J. C. Yanch

Abstract

Preparations are ongoing to test the viability and usefulness of an accelerator source of epithermal neutrons for ultimate use in a clinical environment. This feasibility study is to be conducted in a shielded room located on the Massachusetts Institute of Technology (MIT) campus and will not involve patient irradiations. The accelerator production of neutrons is based on the 7Li(p,n)7Be reaction. A maximum proton beam current of 4 mA at an energy of 2.5 MeV is anticipated. The resultant 3.58 × 1012 neutrons sec−1 have a maximum energy of 800 keV and will be substantially moderated. This paper describes the Monte Carlo methods used to estimate the neutron and photon dose rates in a variety of locations in the vicinity of the accelerator, as well as the shielding configuration required when the device is run at maximum current. Results indicate that the highest absorbed dose rate to which any individual will be exposed is 3 μSv hr−1 (0.3 mrem hr−1). The highest possible yearly dose is 0.2 μSv (2 × 10−2 mrem) to the general public or 0.9 mSv (90 mrem) to a radiation worker in close proximity to the accelerator facility. The shielding necessary to achieve these dose levels is also discussed. The shielding design has been completed and installation of the accelerator has begun.

Keywords

Dose Rate Neutron Yield Boron Neutron Capture Therapy Epithermal Neutron Accelerator Facility 
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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • W. B. Howard
    • 1
    • 2
  • J. C. Yanch
    • 1
    • 2
  1. 1.Department of PhysicsMITUSA
  2. 2.Department of Nuclear Engineering Whitaker College of Health Sciences and TechnologyMITCambridgeUSA

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