\begin{table}%t1
    \caption{Fit results for different spectral models. The
    differential flux normalisation~$I_0$ and the integral flux above~1~TeV $(I({>}1~{\rm TeV}))$ are given in units of $10^{-12}~{\rm cm}^{-2}~{\rm s}^{-1}~{\rm TeV}^{-1}$ and
    $10^{-12}~{\rm cm}^{-2}~{\rm s}^{-1}$, respectively. The power-law fit is clearly an~inappropriate description of the data, a~power~law with an~exponential cutoff
    (row~2), a~power~law with an~energy dependent photon index (row~3), and a~broken power~law (row~4; in the formula, the parameter $S = 0.4$ describes the sharpness of the transition from~$\Gamma_1$ to~$\Gamma_2$ and it is fixed in the fit) are equally likely descriptions of the HESS~data. Note that when fitting a~broken power law to the data, some of the fit parameters are     highly correlated.}\label{table:fits}
    %\centering
\par
    \begin{tabular}{*{7}{l}}
      \hline
      \hline
      Fit Formula & \multicolumn{4}{c}{Fit Parameters} &
      $\chi^2$~(d.o.f.) & $I({>}1~{\rm TeV})$ \\
      \hline
      \noalign{\smallskip}
      $I_0\ E ^ {-\Gamma}$ & $I_0 = 17.1
      \pm 0.5$ & $\Gamma = 2.26 \pm 0.02$ & & &
      85.6 (23) & $13.5 \pm 0.4$ \\[1.4ex]
      $I_0\ E ^ {-\Gamma}\ \exp~ (-E / E_{{\rm c}})$ & $I_0 = 20.4
      \pm 0.8$ & $\Gamma = 1.98 \pm 0.05$ & $E_{{\rm c}} = 12 \pm
      2 $ & & 27.4 (22) & $15.5 \pm 1.1$ \\[1.4ex]
      $I_0\ E ^ {-\Gamma + ~ \beta\ \log E}$ & $I_0 = 19.7
      \pm 0.6$ & $\Gamma = 2.08 \pm 0.04$ & $\beta = -0.30 \pm
      0.04 $ & & 25.5 (22) & $15.6 \pm 0.7$ \\[1.4ex]
      $I_0\ E / E_{{\rm B}} ^ {-\Gamma_1}\ \left( 1 + E /
      E_{{\rm B}} ^ {1 / S } \right) ^ {~ S ~ (\Gamma_2
      - \Gamma_1)}$ & $I_0 = 0.4^{+0.6}_{-0.2}$ & $\Gamma_1
      = 2.06 \pm 0.05$ & $\Gamma_2 = 3.3 \pm 0.5$ & $ E_{{\rm B}} =
      6.7 \pm 2.7 $ & 26.2 (21) & $15.4 \pm 0.8$ \\
\hline
    \end{tabular}
  \end{table}