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Multicolour photometry and Coravel observations of stars in the southern open cluster IC 2488 We present new UBV photoelectric observations of 119 stars in the fieldof the southern open cluster IC 2488, supplemented by DDO and Washingtonphotometry and Coravel radial velocities for a sample of red giantcandidates. Nearly 50% of the stars sampled - including three red giantsand one blue straggler - are found to be probable cluster members.Photometric membership probabilities of the red giant candidates showgood agreement with those obtained from Coravel data. A mean radialvelocity of (-2.63 +/- 0.06) km s-1 is derived for thecluster giants. The reddening across the cluster is found to be uniform,the mean value being E(B-V) = 0.24 +/- 0.04. IC 2488, located at adistance of (1250 +/- 120) pc from the Sun and 96 pc below the Galacticplane, is most probably not related to the planetary nebula ESO166-PN21. A metal abundance [Fe/H] = 0.10 +/- 0.06 relative to the Sunis determined from DDO data of the red giant members, in good agreementwith the [Fe/H] values derived from five independent Washingtonabundance indices. An age of 180 Myr is determined from the fitting ofisochrones computed with convective overshooting for Z = 0.019. Theisochrone for log t = 8.25 reproduces remarkably well not only themorphology of the upper main sequence but also the observed red giantpattern.Based on observations made at Las Campanas Observatory (Chile) and CerroTololo Inter-American Observatory (Chile), National Optical AstronomyObservatories, operated by the Association of the Universities forResearch in Astronomy, Inc., under contract with the National ScienceFoundation and on observations collected with the Danish 1.54-mtelescope at the European Southern Observatory, La Silla (Chile).Tables 1 and 4b are only available in electronic from at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/399/543
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