\begin{table}%t5 \caption{\label{phot_table}Overview of the infrared photometry of $\ell$~Car and RS~Pup from the present work and bibliography. All flux densities are corrected for interstellar extinction, except longwards of 30~$\mu$m, where it is considered negligible. The ``$\bullet$'' symbols in the ``Fit'' column indicate the photometry used for the synthetic spectrum fitting. $\lambda_0$~is the average of the half maximum extreme wavelengths of each instrument/filter combination, and $\Delta \lambda$ the half-bandwidth. $\lambda_{\rm eff}$~is the effective wavelength of the measurement considering the spectral energy distribution of the star. The ``Ap.''~column lists the effective radius of the aperture over which the flux density was measured, when this parameter was available. In the ``Ref.''~column, the references are the following: F07~= Fouqu\'e et~al. (\cite{fouque07}), I86~= IPAC (\cite{ipac86}), H88~= Helou \& Walker (\cite{helou88}), K08~= present work, S04~= Smith et~al. (\cite{smith04}). ``$\alpha$''~is the measured flux density excess, expressed in percentage of the photospheric flux (see Sect.~\ref{sed-section} for details), except for RS~Pup's three longest wavelengths, where it is expressed in stellar flux units, followed by~``$\times$''. The last column~``$N\sigma$'' gives the detection level in number of times the rms~uncertainty.} \par \small%\centerline { \begin{tabular}{lcclccclllr} \hline \hline Inst.~/ & Band & Fit & $\lambda_0 \pm \Delta \lambda$ & $\lambda_{\rm eff}$ & Ap. & Flux density & Flux density & Ref. & $\alpha \pm \sigma(\alpha)$ & $N\sigma$\\ {\it System} & & & [$\mu$m] & [$\mu$m] & [\arcsec] & [${\rm W/m}^{2}/\mu{\rm m}$] & [Jy] & & [\%] & \\ \hline $\mathbf{\ell}$~{\bf Car} \\ {\it Johnson} & $B$ & $\bullet$ & $0.44 \pm 0.05$ & 0.44 & $-$ & $1.13 \pm 0.03$~$\times$ $10^{-09}$ & $72.6 \pm 2.0$ & F07 & $-1.5 \pm 2.8$ & --0.5 \\ {\it Johnson} & $V$ & $\bullet$ & $0.55 \pm 0.04$ & 0.56 & $-$ & $1.80 \pm 0.05$~$\times$ $10^{-09}$ & $181 \pm 5.1$ & F07 & $1.0 \pm 2.8$ & 0.3 \\ {\it Cousins} & $I_{\rm c}$ & $\bullet$ & $0.75 \pm 0.11$ & 0.75 & $-$ & $1.47 \pm 0.04$~$\times$ $10^{-09}$ & $274 \pm 7.7$ & F07 & $3.5 \pm 2.9$ & 1.2 \\ {\it 2MASS} & $J$ & $\bullet$ & $1.25 \pm 0.15$ & 1.22 & $-$ & $7.34 \pm 0.35$~$\times$ $10^{-10}$ & $382 \pm 18$ & F07 & $4.3 \pm 4.9$ & 0.9 \\ {\it 2MASS} & $H$ & $\bullet$ & $1.62 \pm 0.10$ & 1.65 & $-$ & $3.91 \pm 0.18$~$\times$ $10^{-10}$ & $342 \pm 16$ & F07 & $-4.5 \pm 4.7$ & --1.0 \\ {\it 2MASS} & $K$ & $\bullet$ & $2.20 \pm 0.30$ & 2.16 & $-$ & $1.67 \pm 0.08$~$\times$ $10^{-10}$ & $269 \pm 13$ & F07 & $-1.1 \pm 4.7$ & --0.2 \\ COBE$^{*}$ & 3.5~$\mu$m & & $3.57 \pm 0.49$ & 3.55 & $\infty$ & $3.03 \pm 0.41$~$\times$ $10^{-11}$ & $127 \pm 17$ & S04 & $8.4 \pm 15$ & 0.6 \\ IRAC & I1 & & $3.54 \pm 0.39$ & 3.55 & 24 & $2.78 \pm 0.08$~$\times$ $10^{-11}$ & $117 \pm 4$ & K08 & $3.1 \pm 3.1$ & 1.0 \\ IRAC & I2 & & $4.51 \pm 0.51$ & 4.49 & 24 & $1.01 \pm 0.03$~$\times$ $10^{-11}$ & $68 \pm 2$ & K08 & $-0.3 \pm 3.0$ & --0.1 \\ COBE$^{*}$ & 4.9~$\mu$m & & $4.93 \pm 0.37$ & 4.90 & $\infty$ & $7.47 \pm 1.22$~$\times$ $10^{-12}$ & $60 \pm 10$ & S04 & $11 \pm 18$ & 0.6 \\ IRAC & I3 & & $5.73 \pm 0.70$ & 5.73 & 24 & $4.23 \pm 0.13$~$\times$ $10^{-12}$ & $46.3 \pm 1.4$ & K08 & $4.3 \pm 3.1$ & 1.4 \\ IRAC & I4 & & $7.89 \pm 1.44$ & 7.87 & 24 & $1.41 \pm 0.04$~$\times$ $10^{-12}$ & $29.1 \pm 0.9$ & K08 & $8.6 \pm 3.3$ & 2.6 \\ VISIR & PAH1 & & $8.59 \pm 0.42$ & 8.60 & 1.3 & $9.96 \pm 0.38$~$\times$ $10^{-13}$ & $24.6 \pm 0.9$ & K08 & $14.9 \pm 4.4$ & 3.4 \\ IRAS$^{**}$ & 12~$\mu$m & & $11.5 \pm 3.5$ & 11.22 & 25 & $4.32 \pm 0.17$~$\times$ $10^{-13}$ & $18.1 \pm 0.7$ & I86 & $17.1 \pm 4.7$ & 3.6 \\ VISIR & PAH2 & & $11.25 \pm 0.59$ & 11.25 & 1.3 & $3.46 \pm 0.12$~$\times$ $10^{-13}$ & $14.6 \pm 0.5$ & K08 & $16.1 \pm 4.2$ & 3.9 \\ VISIR & SiC & & $11.85 \pm 2.34$ & 11.79 & 1.3 & $3.00 \pm 0.07$~$\times$ $10^{-13}$ & $13.9 \pm 0.3$ & K08 & $16.7 \pm 2.9$ & 5.8 \\ COBE$^{*}$ & 12~$\mu$m & & $12.71 \pm 4.08$ & 12.35 & $\infty$ & $3.64 \pm 2.89$~$\times$ $10^{-13}$ & $19 \pm 15$ & S04 & $18.6 \pm 94$ & 0.2 \\ IRAS$^{**}$ & 25~$\mu$m & & $24 \pm 6$ & 23.34 & 25 & $2.37 \pm 0.14$~$\times$ $10^{-14}$ & $4.31 \pm 0.26$ & I86 & $25.3 \pm 7.5$ & 3.4 \\ MIPS & M1 & & $23.5 \pm 2.7$ & 23.68 & 35 & $2.00 \pm 0.08$~$\times$ $10^{-14}$ & $3.73 \pm 0.15$ & K08 & $23.4 \pm 4.9$ & 4.7 \\ IRAS$^{**}$ & 60~$\mu$m & & $62 \pm 17$ & 59.32 & 60 & $7.63 \pm 0.69$~$\times$ $10^{-16}$ & $0.90 \pm 0.08$ & I86 & $51.3 \pm 14$ & 3.8 \\ MIPS & M2 & & $70.4 \pm 9.54$ & 71.42 & 30 & $2.63 \pm 0.13$~$\times$ $10^{-16}$ & $0.45 \pm 0.02$ & K08 & $30.5 \pm 6.5$ & 4.7 \\ \hline {\bf RS~Pup} \\ {\it Johnson} & $B$ & $\bullet$ & $0.44 \pm 0.05$ & 0.44 & $-$ & $1.56 \pm 0.04$~$\times$ $10^{-10}$ & $10.1 \pm 0.3$ & F07 & $1.5 \pm 2.8$ & 0.5 \\ {\it Johnson} & $V$ & $\bullet$ & $0.55 \pm 0.04$ & 0.56 & $-$ & $2.21 \pm 0.06$~$\times$ $10^{-10}$ & $22.3 \pm 0.6$ & F07 & $-0.5 \pm 2.8$ & --0.2 \\ {\it Cousins} & $R_{\rm c}$ & $\bullet$ & $0.65 \pm 0.15$ & 0.65 & $-$ & $2.30 \pm 0.06$~$\times$ $10^{-10}$ & $32.1 \pm 0.9$ & F07 & $7.7 \pm 3.0$ & 2.6 \\ {\it Cousins} & $I_{\rm c}$ & $\bullet$ & $0.75 \pm 0.11$ & 0.75 & $-$ & $1.76 \pm 0.05$~$\times$ $10^{-10}$ & $32.8 \pm 0.9$ & F07 & $4.6 \pm 2.9$ & 1.6 \\ {\it 2MASS} & $J$ & $\bullet$ & $1.25 \pm 0.15$ & 1.22 & $-$ & $8.40 \pm 0.40$~$\times$ $10^{-11}$ & $43.7 \pm 2.1$ & F07 & $6.3 \pm 5.0$ & 1.3 \\ {\it 2MASS} & $H$ & $\bullet$ & $1.62 \pm 0.10$ & 1.65 & $-$ & $4.28 \pm 0.20$~$\times$ $10^{-11}$ & $37.4 \pm 1.8$ & F07 & $-3.0 \pm 4.6$ & --0.7 \\ {\it 2MASS} & $K$ & $\bullet$ & $2.20 \pm0.30$ & 2.16 & $-$ & $1.82 \pm 0.09$~$\times$ $10^{-11}$ & $29.4 \pm 1.4$ & F07 & $0.9 \pm 4.8$ & 0.2 \\ IRAC & I1 & & $3.54 \pm 0.39$ & 3.55 & 6.1 & $3.41 \pm 0.10$~$\times$ $10^{-12}$ & $14.3 \pm 0.4$ & K08 & $19.2 \pm 3.6$ & 5.4 \\ IRAC & I2 & & $4.51 \pm 0.51$ & 4.49 & 6.1 & $1.31 \pm 0.04$~$\times$ $10^{-12}$ & $8.82 \pm 0.26$ & K08 & $20.8 \pm 3.6$ & 5.7 \\ IRAC & I3 & & $5.73 \pm 0.70$ & 5.73 & 6.1 & $5.16 \pm 0.16$~$\times$ $10^{-13}$ & $5.22 \pm 0.17$ & K08 & $18.7 \pm 3.6$ & 5.3 \\ IRAC & I4 & & $7.89 \pm 1.44$ & 7.87 & 6.1 & $1.49 \pm 0.05$~$\times$ $10^{-13}$ & $3.08 \pm 0.09$ & K08 & $8.2 \pm 3.2$ & 2.5 \\ VISIR & PAH1 & & $8.59 \pm 0.42$ & 8.60 & 1.3 & $1.03 \pm 0.02$~$\times$ $10^{-13}$ & $2.53 \pm 0.06$ & K08 & $11.4 \pm 2.5$ & 4.5 \\ IRAS$^{**}$ & 12~$\mu$m & & $11.5 \pm3.5$ & 11.22 & 25 & $5.15 \pm 0.36$~$\times$ $10^{-14}$ & $2.16 \pm 0.15$ & I86 & $31 \pm 9.2$ & 3.4 \\ VISIR & PAH2 & & $11.25 \pm 0.59$ & 11.27 & 1.3 & $3.76 \pm 0.16$~$\times$ $10^{-14}$ & $1.59 \pm 0.16$ & K08 & $18.8 \pm 5.2$ & 3.6 \\ IRAS$^{**}$ & 25~$\mu$m & & $24 \pm 6$ & 23.34 & 25 & $3.96 \pm 0.28$~$\times$ $10^{-15}$ & $0.72 \pm 0.05$ & I86 & $96 \pm 14$ & 7.0 \\ MIPS & M1 & & $23.5 \pm 2.7$ & 23.68 & 180 & $4.21 \pm 0.17$~$\times$ $10^{-15}$ & $0.79 \pm 0.03$ & K08 & $145 \pm 9.8$ & 15 \\ IRAS & 60~$\mu$m & & $62 \pm 17$ & 59.32 & $\infty$ & $1.19 \pm 0.26$~$\times$ $10^{-14}$ & $13.9 \pm 3.1$ & H88 & $220 \pm 49\times$ & 4.5 \\ MIPS$^{***}$ & M2 & & $70.4 \pm 9.5$ & 71.42 & $\infty$ & $9.94 \pm 0.50$~$\times$ $10^{-15}$ & $16.9 \pm 0.9$ & K08 & $463 \pm 23\times$ & 20 \\ IRAS & 100~$\mu$m & & $103 \pm 18$ & 100.3 & $\infty$ & $7.87 \pm 1.57$~$\times$ $10^{-15}$ & $26.4 \pm 5.3$ & H88 & $1~430 \pm 290\times$ & 5 \\ \hline \end{tabular}} \medskip $^{*}$ The angular resolution of COBE/DIRBE is $\approx$$0.7^\circ$, its aperture is thus considered as infinitely large. \\ $^{**}$ The IRAS Point Source Catalogue (IPAC \cite{ipac86}) apertures were taken as the 80\% encircled energy from Beichman et~al. (\cite{beichman88}). \\ $^{***}$ The MIPS/M2 flux density of RS~Pup's CSE is the integral of the Gaussian profile adjusted in Sect.~\ref{cse-sb}. \end{table}