\begin{table}%t5
\caption{\label{PN_ul}$3\sigma$ upper limits for planetary nebulae in the
SMC observed with \textit{XMM-Newton} (Except for SMP SMC 25 for which we report the detected count rate).}
%\centerline
{\small
\begin{tabular}{lcccc} 
\hline\hline
\noalign{\smallskip}
Name$^{(1)}$ & Rate$^{(2)}$ & $L_{\rm BB}^{(3)}$ & $L_{\rm TB}^{(4)}$ & Observation date \\
	& ($10^{-3}$ cts~s$^{-1}$)	 & ($10^{34}$~erg~s$^{-1}$) & ($10^{34}$~erg~s$^{-1}$) & \\
\noalign{\smallskip}
\hline\noalign{\smallskip}
SMP SMC 5	 &   3.7 &  67.5 &   2.5 & 2006/03/27 \\
SMP SMC 7	 &   1.1 &  20.5 &   0.8 & 2009/10/20 \\
SMP SMC 8	 &   2.2 &  40.6 &   1.5 & 2009/11/09 \\
SMP SMC 9	 &   1.5 &  27.5 &   1.0 & 2009/10/03 \\
SMP SMC 10	 &   2.9 &  53.5 &   2.0 & 2009/09/27 \\
SMP SMC 12$^*$&   3.2 &  93.9 &   2.7 & 2007/10/28 \\
SMP SMC 13$^*$&   1.7 &  50.6 &   1.5 & 2007/10/28 \\
SMP SMC 14$^*$&   2.6 &  75.0 &   2.2 & 2007/10/28 \\
SMP SMC 16 	 &   2.5 &  45.2 &   1.7 & 2007/06/23 \\
SMP SMC 18 	 &   2.3 &  43.2 &   1.6 & 2007/04/11 \\
SMP SMC 19   &   1.6 &  29.5 &   1.1 & 2006/11/01 \\
SMP SMC 21 	 &   1.7 &  31.4 &   1.2 & 2009/10/09 \\
SMP SMC 23 	 &   1.9 &  35.0 &   1.3 & 2009/10/11 \\
SMP SMC 25 	 &   $3.2\pm0.9$ &  58.5 &   2.2 & 2007/06/04 \\
SMP SMC 27 	 &   1.2 &  22.9 &   0.9 & 2009/06/29 \\
J2 	 &   1.8 &  33.9 &   1.3 & 2009/10/03 \\
J4$^*$   &   3.5 & 102.3 &   3.0 & 2007/10/28 \\
J5       &   2.8 &  51.6 &   1.9 & 2009/10/03 \\
J9 	 &   3.0 &  56.2 &   2.1 & 2007/04/11 \\
J10 	 &   1.9 &  34.7 &   1.3 & 2009/09/27 \\
J12 	 &   1.8 &  33.7 &   1.3 & 2009/09/27 \\
J13      &   7.0 & 129.1 &   4.8 & 2007/06/23 \\
J15      &   2.3 &  42.4 &   1.6 & 2007/06/23 \\
J16      &   2.5 &  46.1 &   1.7 & 2007/06/23 \\
J17 	 &   2.1 &  39.3 &   1.5 & 2007/04/11 \\
J18 	 &   2.0 &  36.7 &   1.4 & 2006/11/01 \\
J21 	 &   1.6 &  28.6 &   1.1 & 2009/11/04 \\
J22 	 &   3.2 &  58.5 &   2.2 & 2007/06/23 \\
J23 	 &  12.7 & 234.2 &   8.7 & 2009/10/11 \\
J24 	 &   4.4 &  80.8 &   3.0 & 2009/10/11 \\
J25 	 &   1.7 &  30.8 &   1.1 & 2009/10/11 \\
J27 	 &   2.4 &  43.5 &   1.6 & 2009/10/11 \\
MG8 	 &   1.6 &  29.1 &   1.1 & 2009/09/27 \\
MG9 	 &   3.6 &  66.9 &   2.5 & 2007/06/06 \\
MG10 	 &   3.2 &  59.4 &   2.2 & 2006/10/03 \\
MG11 	 &   1.6 &  29.1 &   1.1 & 2009/11/30 \\
MA14 	 &   2.1 &  38.0 &   1.4 & 2009/10/20 \\
MA44 	 &   1.8 &  33.0 &   1.2 & 2009/10/18 \\
MA406$^*$&   3.0 &  86.9 &   2.5 & 2007/10/28 \\
MA891 	 &   4.0 &  74.5 &   2.8 & 2002/03/30 \\
MA1357 	 &   4.2 &  76.9 &   2.9 & 2009/10/16 \\
MA1714 	 &   1.6 &  29.0 &   1.1 & 2009/11/16 \\
MA1762 	 &   2.6 &  47.4 &   1.8 & 2009/11/19 \\
M7 	 &   1.9 &  36.0 &   1.3 & 2009/06/29 \\
JD29 	 &   1.7 &  31.5 &   1.2 & 2009/10/18 \\
JD51 	 &   2.8 &  51.8 &   1.9 & 2009/10/09 \\
JD53 	 &   3.5 &  64.2 &   2.4 & 2007/06/06 \\
JD57 	 &   1.3 &  24.2 &   0.9 & 2009/09/25 \\
 \hline 
\end{tabular}}
\tablefoot{The sources marked by a star were observed with the medium optical filter, all the others with the thin one.
(1) The names indicate the following references:
       SMP = \citet{san78},
	   J = \citet{jac80}, % Jacoby 1980	
       MG = \citet{mor85}, % Morgan & Good 1985		
	   MA = \citet{mey93}, %  Meyssonier & Azzopardi 1983
	    M = \citet{mor95}, % Morgan 1995	
      JD = \citet{jac02}; % Jacoby & De Marco 2002
(2) 0.1--1~keV count rate in the EPIC pn camera;
(3) unabsorbed 0.1--1~keV luminosity for a black-body
spectrum with $kT=20$~eV,  $N_{\rm H}=5\times10^{20}$~cm$^{-2}$, and $d=60$~kpc;
(4) as (3) but for a thermal bremsstrahlung with $kT=100$~eV.}
\end{table}