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L. Feynman Rules for Tree Graphs in QED
L.2 Propagators
Spin-0
i
=
.
(L.5)
p 2 − m 2 + i∈
Spin1
2
i
/ p + m
=
= i
.
(L.6)
/ p − m
p 2 − m 2 + i∈
Photon
(
)
i
k
μ k
ν
= k 2 −g
μν + (1 − ξ)
(L.7)
k 2 + i∈
for a general ξ. Calculations are usually performed in the Lorentz or Feynman
gauge with ξ = 1 and photon propagator equal to
μν )
(−g
i
.
(L.8)
k 2 + i∈
L.3 Vertices
Spin-0
−ie(p + p
′ ) μ (for charge +e)
2
2ie g μν
L. Feynman Rules for Tree Graphs in QED
L.2 Propagators
Spin-0
i
=
.
(L.5)
p 2 − m 2 + i∈
Spin1
2
i
/ p + m
=
= i
.
(L.6)
/ p − m
p 2 − m 2 + i∈
Photon
(
)
i
k
μ k
ν
= k 2 −g
μν + (1 − ξ)
(L.7)
k 2 + i∈
for a general ξ. Calculations are usually performed in the Lorentz or Feynman
gauge with ξ = 1 and photon propagator equal to
μν )
(−g
i
.
(L.8)
k 2 + i∈
L.3 Vertices
Spin-0
−ie(p + p
′ ) μ (for charge +e)
2
2ie g μν