\begin{table}%t1 \caption{\label{tab1}Key model parameters, and corresponding spectral, dynamical, and morphological values expected from the calculations.} %\centerline {\small \begin{tabular}{l|l} \hline \hline %& Vela Jr \\ $d$ & 1~kpc \\ $R_{\rm s}$ & 17.5~pc \\ \hline $B_{{\rm d}}$ from X-ray filaments & 139$~{\rm \mu G}$ \\ \hline & \\ $E_{{\rm sn}}$ & $1.3 \times 10^{51}~{\rm erg}$ \\ $M_{{\rm ej}}$ & $3.5~M_{\odot}$ \\ $N_{{\rm g}}(R_{{\rm s}})$ & $0.24~{\rm cm^{-3}}$ \\ $N_{{\rm g}}(r=0)$ & $0.003~{\rm cm^{-3}}$ \\ $k$ & 8 \\ $B_{0}$ & $20~{\rm \mu G}$ \\ $\eta$ & $3 \times 10^{-4}$ \\ $K_{{\rm ep}}$ & $3 \times 10^{-4}$ \\ $f_{{\rm re}}$ & 1 \\ \hline $t_{{\rm sn}}$ & 3745~yr \\ $V_{{\rm s}}(t_{{\rm sn}})$ & $1316~{\rm km~s^{-1}}$ \\ $\sigma(t_{{\rm sn}})$ & 5.2 \\ $\sigma_{{\rm s}}(t_{{\rm sn}})$ & 3.1 \\ $M_{\rm s}(t_{{\rm sn}})$ & $25~M_{\odot}$ \\ $E_{{\rm c}}(t_{{\rm sn}})$ & $4.6 \times 10^{50}~{\rm erg}$ \\ $B_{{\rm d}}(t_{{\rm sn}})$(=$\sigma B_{0}$) & $104~{\rm \mu G}$ \\ \hline $P_{{\rm c}}/(\rho_{0}V_{{\rm s}}^{2})$ & 0.145 \\ $B_{0}^{2}/(8\pi P_{{\rm c}}) $ & $ 6.5\times 10^{-3}$ \\ \hline \end{tabular}} \par \medskip Parameter description: the quantities $d$ and $R_{\rm s}$ denote the assumed distance and the radius of the source, respectively, $B_{\rm d}$ is the internal magnetic field strength, as determined from the thickness of observed \mbox{X-ray} filaments cf. Eq.~(1), and $E_{\rm sn}$ is the total hydrodynamic explosion energy; $M_{\rm ej}$, $M_{\rm s}(t_{{\rm sn}})$, $N_{\rm g}(R_{\rm s})$, and $N_{\rm g}(r=0)$ are the ejected mass, the swept-up mass, the circumstellar gas number density at the SNR shock, and the number density at the centre, respectively; $k$ is the power law index of the ejecta velocity distribution; $B_0$ is the assumed amplified magnetic field strength in the upstream region of the shock precursor, while $\eta$ and $K_{\rm ep}$ denote the assumed proton injection rate and energetic electron-to-proton ratio, respectively; $t_{\rm sn}$ is the calculated age of the SNR; $V_{\rm s}(t_{\rm sn})$, $\sigma(t_{\rm sn})$, $\sigma_{\rm s}(t_{\rm sn})$, $E_{\rm c}(t_{\rm sn})$, and $B_{\rm d}(t_{\rm sn})$ are the resulting values of the subshock velocity, the total compression ratio, the subshock compression ratio, the total nonthermal energy, and the downstream magnetic field strength, respectively. Finally, $P_{\rm c}$ and $\rho_0 = m_{\rm p}N_{\rm g}(R_{\rm s})$ denote the postshock pressure of accelerated particles and postshock mass density of the gas, respectively. \end{table}