We identified twelve Hodge clusters in our field of observation. Growth curves aperture photometry was applied to eight of them in order to determine the total U (except for C20), B and V magnitudes (Table 7). Local sky background reaches up to diaphragms of about 7 arcsec ( 24pc). This is not much above the diameters given by Hodge ( 17pc). The only exception is C40, noted by Hodge as "loose", with a diameter of 10 arcsec ( 34pc). We have UBV photometry for the brightest stars of each cluster. The integrated magnitudes and colors of the brightest cluster members differ slightly from the total aperture magnitudes and colors.
The (U-B) vs. (B-V) diagram is presented in Fig. 16. The observed distribution of clusters in the color-color (U-B, B-V) diagram can be related to the SWB classification which was originally based on the Gunn photometric system (Bica et al. 1996). It is basically an age sequence. Six clusters from our sample fall into the SWB0 type zone (Bica et al. 1992) for very young clusters associated with the H II regions and ages between 0 and 10Myr. Only C12, noted by Hodge as "red giants", falls into the SWB1 type zone of clusters around 10Myr. The integrated colors of the clusters belonging to this group may reach very red B-V colors owing to a red supergiant phase.
|Figure 16: (U-B) vs. (B-V) diagram for Hodge clusters. The border line between SWB0 and SWB1 zones is shown. Two new cluster candidates are marked by filled circles|
Two new cluster candidates are identified using the method described above. The magnitudes and colors for them are given in Table 7. The new cluster candidates also fall into the SWB0 type zone (Bica et al. 1992) for very young clusters (marked in Fig. 16 by filled circles).
|Figure 17: The FWHM vs. FWQM plot for nonstellar objects (open circles) and sample stars (filled diamonds)|
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