Magnetic fields with photon beams: dose calculation using electron multiple-scattering theory.

D Jette

doi:10.1118/1.1286554

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Magnetic fields with photon beams: dose calculation using electron multiple-scattering theory.

D Jette

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Abstract

Strong transverse magnetic fields can produce large dose enhancements and reductions in localized regions of a patient under irradiation by a photon beam. We have developed a new equation of motion for the transport of charged particles in an arbitrary magnetic field, incorporating both energy loss and multiple scattering. Key to modeling the latter process is a new concept, that of "typical scattered particles." The formulas which we have arrived at are particularly applicable to the transport of, and deposition of energy by, Compton electrons and pair-production electrons and positrons generated within a medium by a photon beam, and we have shown qualitatively how large dose enhancements and reductions can occur. A companion article examines this dose modification effect through systematic Monte Carlo simulations.

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Algorithms Biophysical Phenomena Biophysics Electrons Humans Magnetics Models, Theoretical Monte Carlo Method Normal Distribution Photons Radiometry Radiotherapy Planning, Computer-Assisted Radiotherapy, High-Energy Scattering, Radiation Journal Article Research Support, U.S. Gov't, P.H.S.

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D Jette. 2000. Magnetic fields with photon beams: dose calculation using electron multiple-scattering theory.. https://doi.org/10.1118/1.1286554

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