Energy peak
|
Relative detector sensitivity with HEGP to MEGP collimator
|
Relative peak height to that at 84 keV with HEGP
|
% decrease in sensitivity by attenuation medium
|
---|
Attenuation medium (−)
|
Attenuation medium (+)a
|
Attenuation medium (−)
|
Attenuation medium (+)a
|
MEGP
|
HEGP
|
---|
84
|
99.5
|
98.3
|
NA
|
NA
|
2.9
|
2.3
|
154
|
70.2
|
74.1
|
29.3
|
31.2
|
3.4
|
1.1
|
269
|
69.8
|
69.9
|
18.9
|
18.8
|
4.3
|
4.1
|
351
|
52.0
|
56.8
|
11.2
|
12.0
|
5.5
|
0.9
|
402
|
47.5
|
46.4
|
8.8
|
8.8
|
2.4
|
4.1
|
-
aCT value of a chamber containing attenuation medium enclosing the vial was 350 HU
-
NA not applicable, MEGP medium-energy general purpose, HEGP high-energy general purpose