Backscatter into the beam monitor chamber: implications for dosimetry of asymmetric collimators.

@article{Duzenli1993BackscatterIT,
  title={Backscatter into the beam monitor chamber: implications for dosimetry of asymmetric collimators.},
  author={Cheryl Duzenli and B A McClean and Colin Field},
  journal={Medical physics},
  year={1993},
  volume={20 2 Pt 1},
  pages={363-7}
}
Backscatter from the asymmetric collimators of a linac into the beam monitor chamber (BMC) has been investigated for two accelerators having different BMC configurations. The effect has been quantified as a function of field size and collimator jaw position for 6 and 18 MV beams. The results indicate a maximum 2.5% (6 MV) and 4% (18 MV) decrease in output in one case and a negligible effect in the other case. The experiments indicate that the difference can be attributed to the different… CONTINUE READING