\begin{table}%t5 \par \caption {\label{tab_par}Estimates of the stellar parameters for the IC~2391 members and candidates of IC~2391 discussed in this work. The objects with identification number (ID) from~1 to~29 are the new candidates selected in this work (Sect.~\ref{selection}); three of these candidates show IR excess emission at 24~$\mu$m and are marked by an asterisk. The objects with ID from~30 to~37 are the additional 8 cluster members and candidates showing IR excess emission discussed in Sect.~\ref{sec_debris}.} %\centerline {\begin{tabular}{cccccccc} \hline\hline ID & Designation & $A_V$ & $T_{\rm eff} ^{\bullet}$ & $L_\star$ & $R_\star$ & Mass$^{\dag}$ & Age$^{\dag}$ \\ & & (mag) & (K) &($L _\odot$) &($R_\odot$) &($M_\odot$) & (Myr) \\ \hline 1 & WFI~J08403964-5250429*& 1.63~$\pm$~0.13 & 3000 & 0.003~$\pm$~0.001 & 0.19~$\pm$~0.04 & 0.08~$\pm$~0.02 & 56~$\pm$~20 \\ 2 & WFI~J08404512-5248521 & 0.01~$\pm$~0.06 & 3400 & 0.038~$\pm$~0.017 & 0.56~$\pm$~0.13 & 0.25~$\pm$~0.05 & 14~$\pm$~5 \\ 3 & WFI~J08404578-5301052 & 0.97~$\pm$~0.07 & 4200 & 0.164~$\pm$~0.075 & 0.76~$\pm$~0.18 & 0.75~$\pm$~0.10 & 45~$\pm$~20 \\ 4 & WFI~J08405518-5257227 & 1.80~$\pm$~0.06 & 4200 & 0.256~$\pm$~0.118 & 0.86~$\pm$~0.22 & 0.85~$\pm$~0.10 & 32~$\pm$~10 \\ 5 & WFI~J08410806-5300053 & 0.19~$\pm$~0.10 & 3100 & 0.015~$\pm$~0.007 & 0.43~$\pm$~0.10 & 0.07~$\pm$~0.02 & 6~$\pm$~3 \\ 6 & WFI~J08410814-5255027 & 1.96~$\pm$~0.07 & 4200 & 0.261~$\pm$~0.120 & 0.97~$\pm$~0.22 & 0.90~$\pm$~0.10 & 25~$\pm$~8 \\ 7 & WFI~J08410886-5248387*& 0.50~$\pm$~0.08 & 3000 & 0.012~$\pm$~0.006 & 0.42~$\pm$~0.09 & 0.07~$\pm$~0.02 & 6~$\pm$~3 \\ 8 & WFI~J08410937-5302136 & 0.26~$\pm$~0.07 & 3100 & 0.024~$\pm$~0.011 & 0.54~$\pm$~0.12 & 0.13~$\pm$~0.06 & 7~$\pm$~2 \\ 9 & WFI~J08411865-5258549 & 0.05~$\pm$~0.08 & 3100 & 0.007~$\pm$~0.003 & 0.28~$\pm$~0.06 & 0.11~$\pm$~0.04 & 32~$\pm$~10 \\ 10 & WFI~J08412229-5304471 & 0.03~$\pm$~0.07 & 3100 & 0.031~$\pm$~0.014 & 0.61~$\pm$~0.14 & 0.11~$\pm$~0.04 & 4~$\pm$~2 \\ 11 & WFI~J08413933-5252565 & 0.42~$\pm$~0.06 & 4000 & 0.093~$\pm$~0.043 & 0.64~$\pm$~0.15 & 0.62~$\pm$~0.08 & 91~$\pm$~40 \\ 12 & WFI~J08415360-5257558 & 0.21~$\pm$~0.07 & 3200 & 0.023~$\pm$~0.011 & 0.50~$\pm$~0.12 & 0.20~$\pm$~0.04 & 18~$\pm$~6 \\ 13 & WFI~J08422460-5259575 & 0.07~$\pm$~0.06 & 4800 & 0.288~$\pm$~0.133 & 0.78~$\pm$~0.18 & 0.85~$\pm$~0.10 & 74~$\pm$~30 \\ 14 & WFI~J08423071-5257348 & 0.05~$\pm$~0.06 & 4000 & 0.102~$\pm$~0.047 & 0.67~$\pm$~0.15 & 0.70~$\pm$~0.10 & 45~$\pm$~20 \\ 15 & WFI~J08424731-5309235 & 1.74~$\pm$~0.10 & 2900 & 0.008~$\pm$~0.004 & 0.35~$\pm$~0.08 & 0.05~$\pm$~0.02 & 6~$\pm$~3 \\ 16 & WFI~J08424850-5303187 & 0.03~$\pm$~0.07 & 3000 & 0.011~$\pm$~0.005 & 0.38~$\pm$~0.09 & 0.08~$\pm$~0.02 & 9~$\pm$~4 \\ 17 & WFI~J08425873-5305546 & 0.22~$\pm$~0.06 & 3300 & 0.049~$\pm$~0.023 & 0.68~$\pm$~0.16 & 0.25~$\pm$~0.05 & 9~$\pm$~4 \\ 18 & WFI~J08425988-5305074 & 1.74~$\pm$~0.10 & 3000 & 0.005~$\pm$~0.002 & 0.26~$\pm$~0.06 & 0.07~$\pm$~0.02 & 18~$\pm$~6 \\ 19 & WFI~J08430294-5302259 & 0.63~$\pm$~0.06 & 4000 & 0.252~$\pm$~0.116 & 1.05~$\pm$~0.24 & 0.90~$\pm$~0.10 & 18~$\pm$~6 \\ 20 & WFI~J08431228-5251411 & 3.19~$\pm$~0.19 & 2900 & 0.002~$\pm$~0.001 & 0.18~$\pm$~0.04 & 0.07~$\pm$~0.02 & 64~$\pm$~20 \\ 21 & WFI~J08431860-5306241 & 0.18~$\pm$~0.06 & 4200 & 0.253~$\pm$~0.117 & 0.95~$\pm$~0.22 & 0.85~$\pm$~0.10 & 32~$\pm$~10 \\ 22 & WFI~J08433366-5259549 & 3.51~$\pm$~0.16 & 3000 & 0.003~$\pm$~0.001 & 0.20~$\pm$~0.05 & 0.09~$\pm$~0.02 & 64~$\pm$~20 \\ 23 & WFI~J08433843-5246379 & 2.53~$\pm$~0.06 & 3900 & 0.076~$\pm$~0.035 & 0.61~$\pm$~0.14 & 0.60~$\pm$~0.08 & 90~$\pm$~40 \\ 24 & WFI~J08433939-5307563 & 0.02~$\pm$~0.07 & 3000 & 0.016~$\pm$~0.007 & 0.47~$\pm$~0.11 & 0.08~$\pm$~0.02 & 6~$\pm$~3 \\ 25 & WFI~J08433945-5248576 & 0.12~$\pm$~0.08 & 3300 & 0.006~$\pm$~0.003 & 0.23~$\pm$~0.05 & 0.15~$\pm$~0.04 & 80~$\pm$~40 \\ 26 & WFI~J08434640-5257036 & 0.12~$\pm$~0.10 & 4200 & 0.180~$\pm$~0.083 & 0.80~$\pm$~0.19 & 0.75~$\pm$~0.08 & 50~$\pm$~20 \\ 27 & WFI~J08434751-5250136 & 2.00~$\pm$~0.06 & 4000 & 0.110~$\pm$~0.051 & 0.69~$\pm$~0.16 & 0.70~$\pm$~0.08 & 45~$\pm$~20 \\ 28 & WFI~J08434909-5307269 & 0.01~$\pm$~0.08 & 3200 & 0.007~$\pm$~0.003 & 0.26~$\pm$~0.06 & 0.11~$\pm$~0.03 & 32~$\pm$~10 \\ 29 & WFI~J08440199-5310356 & 0.41~$\pm$~0.07 & 4000 & 0.083~$\pm$~0.038 & 0.60~$\pm$~0.14 & 0.62~$\pm$~0.08 & 80~$\pm$~40 \\ \hline 30 & WFI~J08404683-5302487*& 0.16~$\pm$~0.17 & 4200 & 2.128~$\pm$~0.001 & 2.77~$\pm$~0.05 & 1.40~$\pm$~0.20 & 5~$\pm$~2 \\ % 31 & WFI~J08410019-5249088*& 0.77$^\ddag$ & 3800$^\ddag$ & 0.185$^\ddag$ & 0.97$^\ddag$ & 0.75$^\ddag$ & 20$^\ddag$ \\ %Robitaille 32 & WFI~J08412176-5247289*& 0.22~$\pm$~0.15 & 4300 & 1.087~$\pm$~0.001 & 1.80~$\pm$~0.01 & 1.40~$\pm$~0.20 & 6~$\pm$~3 \\ % 33 & WFI~J08412550-5300154*& 0.13$^\ddag$ & 4300$^\ddag$ & 0.700$^\ddag$ & 2.48$^\ddag$ & 1.20$^\ddag$ & 10$^\ddag$ \\ %Robitaille 34 & WFI~J08413601-5309274*& 0.17~$\pm$~0.07 & 3000 & 0.012~$\pm$~0.006 & 0.39~$\pm$~0.09 & 0.07~$\pm$~0.02 & 7~$\pm$~3 \\ 35 & WFI~J08413888-5259492*& 0.44$^\ddag$ & 4100$^\ddag$ & 0.101$^\ddag$ & 1.13$^\ddag$ & 0.65$^\ddag$ & 80$^\ddag$ \\ %Robitaille 36 & WFI~J08414904-5255192*& 0.05$^\ddag$ & 3700$^\ddag$ & 0.127$^\ddag$ & 0.95$^\ddag$ & 0.65$^\ddag$ & 16$^\ddag$ \\ %Robitaille 37 & WFI~J08415780-5252140*& 0.24~$\pm$~0.2 & 4000 & 0.203~$\pm$~0.069 & 0.74~$\pm$~0.16 & 0.85~$\pm$~0.10 & 25~$\pm$~8 \\ \hline \end{tabular}} \par \smallskip $^\bullet$ {The uncertainty on $T_{\rm eff}$ is assumed to be 250~K on average (see Sect.~\ref{par}).}\\ $^\dag$ {From the evolutionary models by \citet{Bar98} and \citet{Cha00}.}\\ $^\ddag$ {From the \citet{Rob06} models for young stellar objects (see Sect.~\ref{note_obj}).}\\ $^*$ {Object showing IR excess emission at 24~$\mu$m.} \end{table}