INVESTIGADORES
PIATTI Andres Eduardo
congresos y reuniones científicas
Título:
Fotometría BVI y espectroscopía integrada de los cúmulos abiertos muy jóvenes Ruprecht 119, NGC 6318 y BH 245
Autor/es:
PIATTI, ANDRÉS E.; BICA, EDUARDO; CLARIA OLMEDO, JUAN JOSÉ
Lugar:
Tucumán
Reunión:
Congreso; Reunión Anual de la Asoc. Argentina de Astronomía; 2000
Resumen:
We present CCD BVI observations obtained for stars in the fields of the
unstudied or poorly studied open clusters Ruprecht 119, NGC 6318, and BH
245 projected close to the direction towards the Galactic centre. We
measured V magnitude and B-V and V-I colors for about 600 stars reaching
down to V ~19 mag. From the analysis of the color-magnitude diagrams, we
confirmed the physical reality of the clusters and derived their
reddening, distance and age for the first time. In addition, we obtained
flux-calibrated integrated spectra in the range 3500-9200 Å for
the cluster sample. Using the equivalent widths of the Balmer lines and
comparing the cluster spectra with template spectra we derive both
foreground reddening and age. The photometric and spectroscopic results
reveal that the three studied objects are very young open clusters with
ages ranging between 10 and 15 Myr, which have already undergone the H
II region evolutionary phase and are dominated by the upper MS stars.
The clusters, located between 1.1 kpc and 3.3 kpc from the Sun, are
affected by different amounts of interstellar visual absorption (2.4
< Av < 7.0). In particular, BH 245 turned out to be a
highly reddened open cluster located at a distance of scarcely 1.1 kpc.