Optical photometry and Coravel observations of stars in the field of the Hyades-like age cluster NGC 2489

PIATTI, ANDRÉS E.; CLARIA OLMEDO, JUAN JOSÉ; MERMILLIOD, J.C.; PARISI, M.C.; AHUMADA, A.V.

Venezuela

Congreso; Reunión Regional Latinoamericana de Astronomía; 2007

We present CCD $BVI$ photometry for 2182 stars in the field of the open cluster NGC,2489, supplemented with CORAVEL radial-velocity observations for 7 red giant candidates. The comparison of the cluster colour-magnitude diagram with isochrones of the Padova group yields $E(B-V)$ = 0.30 $pm$ 0.05, $E(V-I)$ = 0.40 $pm$ 0.05, and $V-M_V$ = 12.20 $pm$ 0.25 for log t = 8.70 and Z = 0.019. NGC,2489 is then located at 1.8 $pm$ 0.3 kpc from the Sun and 25 pc below the Galactic plane. A cluster angularradius of 6.7´ $pm$ 0.6´, equivalent to 3.5 $pm$ 0.3 pc, is estimated from star counts carried out inside and outside the cluster region. The analysis of the kinematical data allowed us to confirm cluster membership for 6 red giants, one of them being a spectroscopic binary. A mean radial velocity of 38.13 $pm$ 0.33 km s$^{ m -1}$ was derived for the cluster red giants. The properties of a sample of open clusters aligned along the line-of-sight to NGC,2489 are examined