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\section{Functions}\label{sec4}
\begin{equation}
\label{propak}
C_{b,\mu\nu}(k)\ \dot{=} 
\end{equation}
We define the cutoff function
\begin{eqnarray}\label{siLa0La}
\sigma_{\Lambda,\Lambda_0}(k^2)\ \dot{=} \ \sigma_{\Lambda_0}(k^2)-\sigma_{\Lambda}(k^2)\ ,
\end{eqnarray}
where
\begin{eqnarray}\label{siLa}
\sigma_\Lambda(k^2)
\end{eqnarray}
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