Metallicity distribution on the galactic disk

Depending mainly on UBVCCD data, the metallicities of 91 open star clusters nearby the galactic disk have been estimated using Cameron's [A&A 147 (1985b) 39] method. The metallicity radial gradient along the galactic plane is found to be -0.09 dex/kpc; which is in a very good agreement with Panagia and Tosi [A&A 96 (1981) 306] and Carraro et al. [MNRAS 296 (1998) 1045]. Vertically on the galactic disk, within about 800 pc, the metallicity gradient is found to be so trivial. An average age-metallicity relation has been examined, which confirms the previous suggestion that the metallicity of a cluster depending mainly on its position on the galactic disk more than its age. (C) 2003 Elsevier B.V. All rights reserved.