\begin{table}%t1 %\centering \par \caption {\label{tab1}Summary of RSG candidates and their properties. {\it Top panel}: the core group of~15 {\it photometrically} selected stars regarded as prime cluster candidates; {\it second panel}: likely cluster members; {\it third panel}: stars of interest, as defined in Sect.~2 and {\it fourth panel}: likely foreground RSG identified by spectroscopy and included for completeness. Note that based on spectroscopy, we also consider it likely that star~S16 is a cluster member and treat it as such in the text. Co-ordinates and near-IR magnitudes are from 2MASS, with mid-IR ($\sim$5--25~$\mu$m) magnitudes from the Galactic plane surveys of GLIMPSE/{\it Spitzer} (Benjamin et~al. \cite{benjamin}) and the {\it Midcourse Source Experiment (MSX)} (Egan et~al. \cite{egan}). We also provide the dereddened {\it MSX} $(A-C)$~colour (adopting the prescription of Messineo et~al. \cite{maria}), which is a diagnostic of emission from circumstellar dust (and hence proxy for mass loss) and the spectral type of the stars, where available (Sect.~3).} \begin{tabular}{lccccccccccccc} \hline \hline ID & \multicolumn{2}{c}{Co-ordinates (J2000)} & & 2MASS & & GLIMPSE & {\it Spitzer} & & & {\it MSX} & & & Spec. \\ & RA & Decln. & $J$ & $H$ & $K_{\rm s}$ & 5.8~$\mu$m & 8.0~$\mu$m & A & C & D & E & (A-C) & type \\ \hline S1 & 18 45 23.60 &--03 24 13.9 & 8.55& 6.54 &5.58 & 4.73 & 4.50 & -- & -- & -- & -- & -- & RSG \\ S2 & 18 45 26.54 &--03 23 35.3 & 8.53& 6.62 &5.75 & 4.92 & 4.63 & 4.30 & 3.39 & -- & -- & -- & M3~Ia \\ S3 & 18 45 24.34 &--03 22 42.1 & 8.54& 6.43 &5.35 & 4.19 & 4.14 & -- & -- & -- & -- & -- & M4~Ia \\ S4 & 18 45 25.31 &--03 23 01.1 & 8.42& 6.39 &5.31 & 4.08 & 4.04 & 3.97 & 3.12 & 3.21 & -- & 0.85 & M3~Ia \\ S5 & 18 45 23.26 &--03 23 44.1 & 8.51& 6.52 &5.52 & 4.45 & 4.20 & 3.78 & 2.82 & 3.15 & -- & 0.96 & M2~Ia \\ S6 & 18 45 19.39 &--03 24 48.3 & 9.06& 6.97 &6.04 & 5.24 & 5.20 & 4.71 & -- & -- & -- & -- & RSG \\ S7 & 18 45 24.18 &--03 23 47.3 & 9.12& 7.10 &6.20 & 5.22 & 4.84 & -- & -- & -- & -- & -- & M0~Ia \\ S8 & 18 45 20.06 &--03 22 47.1 & 9.53& 7.29 &6.30 & 5.46 & 5.43 & 5.60 & -- & -- & - & -- & K5~Ia \\ S9 & 18 45 28.13 &--03 22 54.6 & 9.34& 7.26 &6.29 & 5.49 & 5.44 & -- & -- & -- & -- & -- & M0~Ia \\ S10 & 18 45 16.56 &--03 23 45.1 & 9.65& 7.43 &6.43 & 5.57 & 5.52 & 5.45 & -- & -- & -- & -- & M0~Ia \\ S11 & 18 45 26.31 &--03 20 03.3 & 9.18& 7.27 &6.46 & 5.77 & 5.78 & 5.87 & -- & -- & -- & -- & RSG \\ S12 & 18 45 29.12 &--03 28 35.6 & 9.78& 7.86 &6.93 & 6.57 & 6.26 & 6.23 & -- & -- & -- & -- & -- \\ S13 & 18 45 05.51 &--03 20 19.6 & 8.18& 5.97 &4.96 & -- & -- & 3.59 & 2.43 & 2.45 & -- & 1.16 & RSG \\ S14 & 18 45 29.02 &--03 22 37.4 & 9.51& 7.08 &5.89 & 4.79 & 4.61 & 4.43 & -- & -- & -- & -- & RSG \\ S15 & 18 45 16.84 &--03 21 14.6 & 9.33& 6.92 &5.69 & 4.12 & -- & 3.26 & 1.85 & 1.66 & 0.92 &1.41 & RSG \\\hline S16 & 18 45 20.87 &--03 27 59.6 & 9.32& 6.78 &5.53 & 4.34 & 4.15 & 3.79 & 2.93 & 2.97 & 2.22 &0.86 & RSG \\ S17 & 18 45 38.45 &--03 23 18.1 &10.58& 7.07 &5.27 & -- & -- & 2.09 & 0.65 & 0.45 &--0.121 & 1.44& -- \\ S18 & 18 45 38.65 &--03 21 03.9 &10.07& 7.62 &6.47 & 5.50 & 5.44 & 5.36 & -- & -- & -- &-- & -- \\ S19 & 18 45 37.05 &--03 19 35.1 &10.43& 7.81 &6.52 & 5.44 & 5.40 & 5.42 & -- & -- & -- &-- & -- \\ S20 & 18 45 16.64 &--03 22 33.2 &10.71& 8.28 &7.06 & 5.98 & 5.85 & 5.79 & -- & -- & -- &-- & -- \\ S21 & 18 45 11.81 &--03 18 43.1 &12.27& 8.30 &6.30 & 4.50 & 4.32 & 4.27 & 3.31 & 3.17 & -- &0.96 & -- \\ S22 & 18 45 12.69 &--03 23 30.7 &10.51& 8.04 &6.78 & 5.49 & 5.41 & 5.36 & -- & -- & -- &-- & -- \\\hline S23 & 18 45 48.82 &--03 24 23.1 & 9.67& 7.36 &5.85 & -- & -- & 2.92 & 2.00 & 1.84 & 1.27 &0.92 & -- \\ S24 & 18 45 50.34 &--03 24 21.8 &10.84& 8.08 &6.74 & -- & -- & -- & -- & -- & -- &-- & -- \\ S25 & 18 45 45.61 &--03 20 42.8 &11.27& 8.43 &7.10 & 5.88 & 5.96 & -- & -- & -- & -- &-- & -- \\ S26 & 18 45 35.02 &--03 19 58.2 &11.43& 8.43 &6.96 & 5.42 & 5.21 & -- & -- & -- & -- & -- & -- \\ S27 & 18 45 26.61 &--03 23 24.7 &11.26& 8.78 &7.46 & 6.01 & 5.81 & -- &-- &-- & -- &-- & -- \\\hline S28 & 18 45 17.75 &--03 26 38.4 & 7.78& 6.14 &5.38 & 4.42 & 4.17 & 3.18 & 3.12 & -- & -- &1.19 & RSG \\ \hline \end{tabular} \end{table}