Photon Energy
1 Mb
1 kb
1 b
10 mb
10 eV 1 keV 1 MeV 1 GeV 100 GeV
(b) Lead (Z = 82)
− experimental σ
tot
σ
p.e.
κ
e
Cross section (barns/atom)Cross section (barns/atom)
10 mb
1 b
1 kb
1 Mb
(a) Carbon (Z = 6)
σ
Rayleigh
σ
Rayleigh
σ
Compton
σ
Compton
κ
nuc
κ
nuc
κ
e
σ
p.e.
− experimental σ
tot