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Challenges: reference versus relative dosimetry
Reference conditions
Reference dosimetry
Non reference conditions:
Relative dosimetry
- Uniform electron fluence distribution over the
detector.
- Beam spectra at the reference point in ref.
conditions known.
- Detector of choice:
Ion Chambers
- Non-Uniform electron fluence distribution over
the detector.
VOLUME AVERAGING
- Beam spectra at the reference point may differ
from beam spectra at the measuring point.
ENERGY DEPENDENCE; PERTURBATION
FACTORS
- Perturbation in electron fluence caused by the
detector itself
PERTURBATION
FACTORS