INVESTIGADORES
AHUMADA Andrea Veronica
artículos
Título:
The relatively young and metal-poor Galactic open cluster NGC 2194
Autor/es:
PIATTI, ANDRÉS E.; CLARIÁ, JUAN J.; AHUMADA, ANDREA V.
Revista:
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2003 vol. 340 p. 1249 - 1260
ISSN:
0035-8711
Resumen:
We present CCD VIKC photometry down to V~ 21 mag in the field
of the rich open cluster NGC 2194, which is projected towards the
Galactic anticentre direction. We measured V magnitudes and V-I colours
for a total of 2515 stars in a field of 13.6 × 13.6
arcmin2. These data are supplemented with CCD photometry in
the C, M and T1 filters of the Washington system and
photoelectric CMT1T2 photometry of 20 red giant
candidates. Based on the best fits of isochrones computed by the Geneva
and Padova groups to the (V, V-I) colour-magnitude diagram, we derive a
colour excess E(V-I) = 0.75, a cluster distance of 3.2 kpc and an age of
400 Myr. Five independent Washington abundance indices yield a mean
cluster metallicity of [Fe/H]=-0.27 +/- 0.06, which is compatible with
the existence of both a radial and Z gradient in the Galactic disc. NGC
2194 is a relatively young open cluster, whose deficiency in metal
content can be accounted for by the fact that it was born not only far
from the Galactic centre in the outer disc, but also at a relatively
high Z value.