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__In any theory__,the propagator [itex]\Delta[/itex][itex]_{f}[/itex](k) of a field of type f has asymptotic behavior:

[itex]\Delta[/itex][itex]_{f}[/itex](k)~k[itex]^{-2+2sf}[/itex]

where sf is ''spin'' of the field.For massive fields of Lorentz type (A,B) then sf=A+B.

(However,dropping terms that because of gauge invariance have no effect,eg. photon has sf=0)

(QFT of Weinberg Vol 1,&12.1 Degrees of Divergence)