2066-2067 / 2605
Perturbation correction factors
Particles
.
water
air
S
|
water
D
air
D
p
wall
.
p
cel
p
cav
p
dis
The perturbations of the
particle field (esp. the
secondary electrons) due
to the chamber lead to
corrections.
Due to the small energy of secondary electrons: p
Q
= 1 is used for p, ions!
The dose D
water
is not related to the center of the chamber, x, but rather to an
effective point of measurement
: P
eff
= x - 0.72 r (r= chamber radius)
.
.
.