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energy
E
Bremstrahlung production cross
section, Z=74, 10 MeV
0
2
4
6
8
MeV
1
10
100
1000
barn
/
Sr
0
10
20
30
40
50
0.05
0.1
0.5
1
5
10
attenuation coefficient, Z=74
cm
2
/g
MeV
Beam energy spectra
- spectral filtering by the flattening filter
Direct beam spectrum, principal shape.
Spectrum distorted offaxis
towards lower
energies due to less filtration & decreasing
energy with increasing brem angle