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7. Discussion and conclusions

7.1. Evolved stars in the cluster

The spatial distribution of the evolved stars in Be 64 and Be 69, shown in Figs. 15 (click here) and 16 (click here), manifests that evolved stars have preferential distribution in the outskirts of the clusters. Hawarden (1975) has also found that giant branch clump stars in old open clusters are in general less centrally concentrated than the brightest stars remaining on the upper MS.

7.2. Metallicity location relation

Adopting a value of tex2html_wrap_inline1471, the galactocentric distance for the clusters has been calculated. The [Fe/H] value has been obtained by using the relation log Z= 0.977 tex2html_wrap_inline1475 from Bertelli et al. (1994). The various parameters obtained are given in Table 4. The metallicity of these two clusters is in accordance with the radial gradient obtained by Friel & Janes (1993) and Carraro & Chiosi (1994).

The z distance of Be 69 (tex2html_wrap_inline1479 below the formal galactic plane) and  Be 64 (tex2html_wrap_inline1481 above the formal galactic plane) suggests that Be 69 is situated in the anticenter direction of the thin disk whereas the cluster Be 64 may be located in the thick disk. The value of the metallicity for Be 64 (tex2html_wrap_inline1483) is also close to the average value (tex2html_wrap_inline1485) of the metallicity for the thick disk population (Sandage & Fouts 1987).

7.3. Conclusions

(1) We present photometry for two previously unstudied open clusters. Overall morphology of the CMDs of both clusters indicates that clusters are of intermediate age.
(2) The reddening for Be 64 and Be 69 comes out to be tex2html_wrap_inline1487 and tex2html_wrap_inline1489. From mapping of interstellar reddening done by Pandey & Mahra (1987), values of tex2html_wrap_inline1491 and tex2html_wrap_inline1493 have been obtained towards the Be 64 and Be 69 direction, respectively, which are in good agreement with the values obtained in the present study.
(3) The estimated metallicity for the clusters (Z = 0.008, tex2html_wrap_inline1497), and the galactocentric distance of the clusters follow the radial gradient in metallicity obtained by Friel & Janes (1993) and Carraro & Chiosi (1994). The location of Be 69 puts the cluster in the thin disk towards the anticenter direction, whereas the location of Be 64 suggests that the cluster may be a member of the thick disk.
(4) The evolved stars appear to be concentrated in the outskirts of the clusters.

Table 1:
Details of observation

Table 4: Galactic coordinates and estimated parameters of open clusters analysed in the paper


This work is partly supported by the Department of Science and Technology (India) under the grant SP/S2/O -07/93. Authors are thankful to the referee Dr. G. Carraro for useful comments.

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