All Figures

Figure 1: Illustration of the member-selection algorithm for the open cluster Stock 2. Arrows show the sequence of the basic selection phases presented by rectangles. Panel  a) is a sky map of the cluster neighbourhood. Panel  b) shows radial profiles of the projected density; panel  c) is the colour-magnitude diagram; panel  d) is vector point diagram; and panels  e) and f) are "magnitude equations'' ( relations). Additional explanations for each panel are given in Appendix B.

Open with DEXTER


In the text

	Figure 2: Comparison of distance d and colour-excess E(B-V) derived by Loktin et al. (2001) and Loktin (2004) from 3-colour photometry with values determined on the basis of spectral classification.
Open with DEXTER


In the text

	Figure 3: Comparison of derived angular radii with data compiled by Dias et al. (2004). The solid line is the locus of equal radii. Crosses mark clusters with distances  kpc, whereas the dots are nearer clusters. The dashed line separates "large'' and "small'' clusters.
Open with DEXTER


In the text

Figure 4: Comparison of cluster proper motions derived in this study from ASCC-2.5 data with results of a) Robichon et al. (1999); b) Baumgardt et al. (2000); and c) Dias et al. (2001, 2002). Bars show rms-errors. The straight lines are the loci of equal proper motion components. The upper lines and left axes refer to clusters included in our sample and in the comparison samples. The lower lines and right axes are for 35 clusters common to all samples.

Open with DEXTER


In the text

	Figure 5: Comparison of cluster radial velocities derived in this study with data published in Lyngå (1987), Ruprecht et al. (1981), and DLAM. If the mean RV of a cluster is determined from more than two members, error bars are shown.
Open with DEXTER


In the text

Figure 6: Illustration of the adopted algorithm for determination of cluster ages. In Panel  a), the thin curves are isochrones for three different ages ( ; 8.60; 9.00). The dotted curve is the locus of unresolved binaries with mass ratio q=1 for the age . The thick dashed curve is the adopted ZAMS where the dots mark the empirical ZAMS of Schmidt-Kaler (1982). The thick curves to the right of the ZAMS are the blue (s=0.15) and red (i.e., TAMS, s=1.00) borders of the evolved MS. Horizontal lines indicate the EMS spread at MV = 0; 1; 2. Age variations along these lines are shown in Panel  b) as functions of the evolutionary status s, while the blue edge of the evolved MS is marked by the vertical line at s=0.15. Photometric errors in (B-V) of 0.01 mag are converted to corresponding errors in s and shown as bars. Stars marked by letters B,C,D,E are hypothetical cluster members, where B is the brightest MS star. X marks the isochrone base point defined as the cross-section of the corresponding isochrone with the blue edge of the evolved MS. is the magnitude range adopted for the cluster age evaluation. While stars Band C will be included by the algorithm in the age determination, stars Dand E will be rejected.

Open with DEXTER


In the text

Figure 7: Comparison of the derived cluster ages with data published in LGM. Dots indicate clusters where only one star (Nt=1) is used for the age determination, whereas crosses and filled circles are for clusters with Nt=2and Nt>2, respectively. The circle sizes are scaled by the number of stars used for the age determination of a given cluster (cf. Table 1). For clusters with Nt>2, the bars show rms-errors of the averaged ages derived in this paper. For clusters with Nt=2, the bars indicate the scatter and are shown without hats. Triangles are the clusters of group (i), whereas the upside-down triangles mark the group (ii). The dashed line is the locus of equal ages. The solid line shows a regression solution obtained for the complete sample.

Open with DEXTER


In the text

Figure B.1: An example of the atlas: a plot for the open cluster Coma Berenicis.


In the text