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Pencil Beam example, penumbra modeling
Warsaw 2017
16
r
gap
z
gap
Collimator plane
Patient
r
r
proj
gap
2
2
r
proj
z
gap
Collimator plane
Patient
z
gap
At calculation points well inside field limits,
PB width set to zero at patient level not to
wash out effects from heterogeneities
At calculation points in penumbra region,
PB width set to zero at collimator level to
correctly model penumbra width including
effects of in air scattering