
144 Statistical Computing in Nuclear Imaging
TABLE 5.1
Properties of s cintillator and semiconductor mate rials used in nuclear imag-
ing
Property NaI(Tl) BGO LYSO CZT
Density (g/cm
3
) 3.67 7.13 7.40 5.85
Effective atomic number
a
50 74 66 49
Photon yield
b
(per keV) 38 8 20-30 N/A
Hygroscopic yes no no no
a
Effective atomic number is the weighted average of the atomic number of the
components of the material.
b
Photon yield is the average number of low-energy photons produced by the gamma ray
per keV.
Gamma ray AmplificationScintillator
High-energy
photon
Many Low-energy
photons
Electrical s ignal
Reflective
surface
FIGURE 5.10 Scintillation radiation detector.
5.2.2.1 Photomultiplier ...