\begin{table}%t3
%\centering
\par
\caption{\label{tab:Tfit}Temperarture of the sky load pyramids. Quadratic fit coefficients.}  %\centering
                          % used for centering table
\begin{tabular}{l c c}        % centered columns (4 columns)
\hline\hline                 % inserts double horizontal lines
\noalign{\smallskip}
   & $30$~GHz & $44$~GHz \\
   \hline
$a$  &$0.9185 \pm 0.0006$&$0.5430 \pm 0.008$ \\
$b$  &$0.9540 \pm 0.0001$&$0.9795 \pm 0.0008$ \\
$c$  &$0.0008460 \pm 4.4\times 10^{-6}$&$0.000217\pm 1.9\times 10^{-5}$\\
\hline                                   %inserts single line
\end{tabular}
\end{table}