350 Chapter 6. Scintillation Detectors and Photodetectors
Figure 6.2.11: Relative light
yield of pure and doped an-
thracene with respect to irradi-
ation time and integrated flux of
α-particles (11).D.2 P-Terphenyl (C 18 C 14 )
The most desirable characteristic of p-terphenyl crystal is its very short decay time,
making it suitable for spectroscopy of high intensity radiation. However the light
yield of this crystal is quite bad. This shortcoming is overcome by doping the
material with some suitable impurity, which has been shown to increase the light
output to up to 5 times of pureC 18 H 10.
D.3 Stilbene (C 14 H 12 )
Like anthracene, stilbene has also been thoroughly investigated for its possible use
for radiation detection. Although its light output is not as good as anthracene, still
it has found some applications in detection of heavy charged particles. The light
yield of stilbene has been compared with that of anthracene in Fig.6.2.12. Note that
the abscissas in the figure have been reduced byMZ^2 ,withMandZbeing the
mass and charge of the incident particles. This has eliminated the dependence of
light yield on the type of charged particle on the scale of the graph.
6.3 Inorganic Scintillators
Most of the inorganic scintillators have crystalline structures. These materials are
generally more dense and have higher atomic number than organic scintillators. This
makes them attractive in applications where high stopping power for the incident