UBV, DDO and Washington photometric study of late-type evolved stars in the open cluster NGC 2447: membership and chemical composition

UBV, DDO and Washington photometric data for 14 red giant candidates of the open cluster NGC 2447 are presented. Membership results emerging from the application of two photometric criteria are in excellent agreement with those derived from published Coravel radial velocities. A mean cluster reddening E(B-V) = 0.05 + 0.04 is derived. Both the ultraviolet excesses and the cyanogen anomalies of the cluster giants imply [Fe/H] approximately -0.1. Five Washington abundance indicators yield a mean cluster metallicity of Fe/H]_W = -0.09 + 0.06, thus confirming NGC 2447 to be a slightly metal-poor open cluster.Presentamos datos fotometricos UBV, DDO y Washington de 14 estrellas candidatas a gigantes rojas del cumulo abierto NGC 2447. Los resultados que se obtienen al aplicar 2 criterios fotometricos para distinguir miembros fısicos del cumulo muestran excelente acuerdo con los derivados a partir de velocidades radiales Coravel publicadas. Derivamos un enrojecimiento medio E(B-V) = 0.05 ± 0.04 para el cumulo. Tanto los excesos ultravioletas como las anomalıas de cianogeno de las gigantes del cumulo implican [Fe/H] ≈ -0.1. Cinco indicadores de abundancia del sistema de Washington conducen a una metalicidad media de [Fe/H]W = -0.09 ± 0.06, lo que confirma que NGC 2447 es un cumulo abierto ligeramente pobre en metales.Fil: Claria Olmedo, Juan Jose. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lapasset Gomar, Emilio. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Parisi, Maria Celeste. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

IC 2395 and BH 47: only one open cluster in the Vela constellation

We report UBV photoelectric photometry for 273 stars in the fields of the open clusters IC 2395 and BH 47. Our postulate is that, rather than two different clusters in this region of Vela, there is only one, which we call IC 2395 = BH 47. The cluster is centered at about α = 8h42. m5, δ = −48◦06. 8 (2000), its angular diameter being ∼19 . The analysis of the photometric data yields 61 probable cluster members and 16 possible members. Photometric membership probabilities show good agreement with those obtained from a proper motion study for 21 stars in common. The reddening across the cluster appears to be uniform, the mean E(B − V) value being 0.09 ± 0.02. The true distance modulus is (V − MV )0 = 9.52 ± 0.10, corresponding to a distance from the Sun of (800 ± 40) pc and 48 pc below the Galactic plane. The cluster age, determined by fitting isochrones with core overshooting, turns out to be (6 ± 2) Myr. There is a strong likelihood that IC 2395 = BH 47 is physically connected to the Vela OB1C association.Fil: Claria Olmedo, Juan Jose. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lapasset Gomar, Emilio. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Ahumada, Andrea Veronica. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Multicolour photometry and Coravel observations of stars in the southern open cluster IC 2488

We preseent new UBV photoelectric observations of 119 stars in the field of the southern open cluster IC 2488, supplemented by DDO and Washington photometry and Coravel radial velocities for a sample of red giant candidates. Nearly 50% of the stars sampled - including three red giants and one blue straggler - are found to be probable cluster members. Photometric membership probabilities of the red giant candidates show good agreement with those obtained from Coravel data. A mean radial velocity of (-2.63 +/- 0.06) km/s is derived for the cluster giants. The reddening across the cluster is found to be E(B-V) = 0.24 +/- 0.04. IC 2488, located at a distance of (1250 +/- 120) pc from the Sun and 96 below the Galactic plane, is most probably not related to the planetary nebulae ESO 166-PN21. A metal abundance 0.10 +/- 0.06 relative to the Sun is determined from DDO data of the red giant members, in good agreement with the metallicity values derived from five independent Washington abundance indices. An age of 180 Myr is determined from the fitting of isochrones computed with convective overshooting for Z = 0.019. The isochrone for log t = 8.25 reproduces remarkably well not only the morphology of the upper main sequence but also the observed red giant pattern.Fil: Claria Olmedo, Juan Jose. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lapasset Gomar, Emilio. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mermilliod, J. C.. Universite de Lausanne; Suiz

Multicolor Photometry of Red Giant Candidates in the Southern Open Cluster NGC 2447

Photoelectric photometry in the UBV, DDO and Washington systems is presented for 14 late-type giant candidates of the southern open cluster NGC 2447. By applying two independent photometric criteria, nine stars are found to have a high probability of being cluster giants. The photometric membership results are in good agreement with those derived from published Coravel radial velocities. The mean interstellar reddening EB-V = 0.05±0.04 has been derived from the confirmed cluster giants. NGC 2447 has a mean ultraviolet excess = 0.01±0.02 (σ n) with respect to solar composition K giants, and a mean cyanogen anomaly = 0.01±0.02 (σ n), both implying a small metal deficiency ([Fe/H] ≃ -0.1). Five independent Washington abundance indices yield a mean cluster metallicity of [Fe/H] = -0.09±0.06, in agreement with the two previous estimates. Therefore, NGC 2447 is found to be slightly metal-poor.Fil: Claria Olmedo, Juan Jose. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lapasset Gomar, Emilio. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Parisi, Maria Celeste. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentin