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\begin{document}
\resizebox{\textwidth}{!}{
    \begin{tabular}{ c  c c c c c c c}
      \hline
      Region ( $ {\mathrm{\,Me\kern -0.1em V\!/}c^2}$ \xspace) & $\sigma_G$ & $\sigma_C$ & $\alpha_{\rm l}$ & $n_{\rm l}$ & $\alpha_{\rm u}$ & $n_{\rm u}$ & $f$  \\
      \hline
	$[\phantom{0}300,1800]$  & 3.53 & 2.98 & $-$1.15 & 20.0 & 1.15 & 20.0 & $0.39$ \\ 
        $[1800,3400]$ & $6.71\pm0.04$ & $5.67\pm0.02$  & $-1.21\pm0.02$ & $9.1\pm1.0$ & $1.21\pm0.02$ & 20.0 & $0.41\pm0.01$ \\ 
        $[3400,4700]$ & $5.63\pm0.04$ & $4.76\pm0.02$ & $-1.21\pm0.02$ & $8.5\pm0.5$ & $1.21\pm0.02$ & $7.3\pm1.2$ & $0.41\pm0.01$ \\ 
      \hline
    \end{tabular}
}\\
\end{document}
