654 Chapter 11. Dosimetry and Radiation Protection
(b)
(a)
(d)
(c)
TEPC
Tissue
Wall
Figure 11.5.1: Processes leading to
measurement uncertainty in a walled
TEPC as compared to a tissue. (a)
Re-entry effect (b) Scattering effect.
(c) V-track effect. (d) Delta-ray ef-
fect.
whereVtandVbare respectively the track and bulk etch rates. Since the track ratio
V is proportional to the linear energy transfer, therefore with proper calibration it
can be used to determine the absoluteLETof the radiation. The calibration can
be performed by irradiating a similar SSNTD with known radiation.