Positron annihilation in a strong magentic field.

In „<strong>annihilation</strong> <strong>in</strong> flight” process positron or electron
contributs to the energy of emitted photons
hν 1
p
hν m<strong>in</strong>
p
hν max
hν 2
Free particles <strong>in</strong> Lab (From Dirac formula)
2
dσ 2γ
2π rm ⎡
o 0
1 1 E+ 3m0 1 E+
m ⎤
0
=− ⎢ − +
2 2⎥
dEγ E − m0 ⎢⎣
E + m0 2 Eγ( E + m0 − Eγ) 2 Eγ ( E+ m0
−Eγ)
⎥⎦
,
E
=
(m<strong>in</strong>) 0 0
γ
2 2
E+ m0 + E −m0
dσ/dEγ (barn/MeV)
( E+
m ) m 1
m
2
0
( E+
m ) m 1
(max) 0 0
Eγ
= E+
m0
2 2
E+ m 2
0
− E −m0
0.4
E +
=0.2 MeV
0.3
0.2
0.5 MeV
0.1
1 MeV
1.5 MeV
2 MeV
2.5 MeV
Kontrovich et al., The 10th International Symposium
on Orig<strong>in</strong> of Matter and Evolution of Galaxis (OMEG-2010)
0.0
0 1 2 3 4
E γ
(MeV)
255.5 keV
Spectra of <strong>annihilation</strong> <strong>in</strong> flight photon
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