\begin{table}%t4
  \caption{\label{isgrispihexte}Fitted parameters for the fundamental and the first harmonic CRSF.
    }
\par
%\centering
                          % used for centering table
\small\begin{tabular}{l c c c}        % centered columns (3 columns)
\hline\hline                 % inserts double horizontal lines
Parameter & \textit{SPI} & \textit{ISGRI} & \textit{HEXTE}   \\    % table heading 
\hline                        % inserts single horizontal line
{\rm  Fundamental} &  &  &  \\
$E_{c_1}$ (keV) & $\rm 22.7^{+0.9}_{-2.4}$ & $\rm 22.0^{+1.0}_{-1.6}$ & $\rm 20.7^{+1.3}_{-3}$ \\
$\tau_{c_1}$  & $\rm 0.8^{+0.4}_{-0.3}$ & $\rm 0.5^{+1.6}_{-0.18}$ & $\rm 0.5^{+1.3}_{-0.13}$ \\
$\sigma_{c_1}$ (keV) & $\rm 3^{+4}_{-1.7}$ & $\rm 3^{+5}_{-2}$ & $\rm 4^{+6}_{-3}$ \\
{\rm 1{st} Harmonic} &  &  &  \\
$E_{c_2}$ (keV) & $\rm 42^{+4}_{-1.5}$ & $\rm 47^{+3}_{-10}$ & $\rm 48^{+9}_{-7}$ \\
$\tau_{c_2}$  & $\rm 0.9^{+1.0}_{-0.5}$ & $\rm 0.8^{+0.5}_{-0.21}$ & $\rm 0.6^{+1.7}_{-0.3}$ \\
$\sigma_{c_2}$ (keV) & $\rm 3^{+11}_{-1.9}$ & $\rm 10^{+22}_{-6}$ & $\rm 8^{+24}_{-7}$ \\
 & & & \\
$\chi^2_{\nu}$(d.o.f.) & 1.0(14) & 1.1(18) & 0.8(16) \\ 
\hline                                   %inserts single line
\end{tabular}  
\end{table}