\begin{table}%t1
%\centering
\par
\caption{Measured, assumed, and derived values for
different physical quantities at the innermost  starburst region
of NGC~253 (IS), a cylindrical disk with height 70~pc, and its
surrounding disk (SD).\label{model}}
\begin{tabular}{lllll }
\hline\hline
Physical parameters & Symbol & Value & Units & Comment\\
\hline
\par
Distance & $D$ & 2.5 & Mpc & ST
\\
\par
Inclination & $i$ & 78 & degrees & ST \\
\par
Infrared Luminosity of the innermost starburst (IS)
& $L_{\rm IR}$  &$2\times 10^{10}$
 & $L_\odot$ & ST\\
\par
%Infrared peak wavelength & $\lambda_{\rm peak}$ & 100 & $\mu$m &
%ST\\
\par
Radius of the IS &-- & 100 & pc  &
ST\\
\par
Radius surrounding disk (SD) &-- & 1000 & pc  &
ST\\
\par
Uniform density  of the IS & $n_{\rm IS}$ & $\sim$$600$ & cm$^{-3}$
&
ST\\
\par
Uniform density  of the SD & $n_{\rm SD}$ & $\sim$$50$ & cm$^{-3}$ &
ST\\
\par
Gas mass of the IS & $M_{\rm IS}$ & $\sim$$ 3 \times 10^7$ & $M_\odot$ & ST\\
\par
Gas mass of the SD & $M_{\rm SD}$ & $\sim$$ 2.5 \times 10^8$ & $M_\odot$ & ST\\
\par
Supernova explosion rate of the IS & ${\cal R}$ & $\sim$$ 0.08$ & SN
yr$^{-1}$ &
ST\\
\par
Supernova explosion rate of the SD & -- & $\sim $$0.01$ & SN
yr$^{-1}$ &
ST\\
\par
Typical supernova explosion energy & -- &
10$^{51}$ & erg & ST\\
\par
SN energy transferred to cosmic rays & $\eta$ &
$\sim $$10$ & \% & ST \\
\par
Convective velocity & $V$ & 300--600 & km s$^{-1}$ & ST \\
\par
Dust emissivity index & $\sigma$ & 1.5 & -- & OM \\
\par
Dust temperature & $T_{\rm dust}$ & 50 & K & OM \\
\par
Emission measure & EM & $5 \times 10^5$  & pc cm$^{-6}$ & OM \\
\par
Ionized gas temperature & $ T$ &  $10^4$ & K & OM \\
\par
Magnetic field of the IS & $B$ & 300 & $\mu$G & OM \\
\par
Slope of primary injection spectrum & $p$ & 2.2--2.3 &-- & A\\
\par
Maximum energy considered for primaries & -- & 100 & TeV & A
\\
\par
Diffusion coefficient slope & $\mu$ & 0.5 &-- & A\\
\par
%Minimum kin. energy of acc. particles & $E_{\rm
%p,~kin,~ min}$ &  0.01--0.1 & GeV & Assumed \\
\par
Proton to electron primary ratio & $N_{\rm p}/N_{\rm e}$ & 50 & --  &
A\\
\par
Diffusive timescale & $\tau_0$ & 1--10 & Myr & A\\
\par
\hline
\par
\end{tabular}
\end{table}