INVESTIGADORES
PIATTI Andres Eduardo
artículos
Título:
A revision of the fundamental parameters of the open cluster Hogg 15 and the projected star WR 47
Autor/es:
PIATTI, ANDRÉS E.; BICA, EDUARDO; SANTOS JR, JOÂO F.C.; CLARIA OLMEDO, JUAN JOSÉ
Revista:
ASTRONOMY AND ASTROPHYSICS
Referencias:
Año: 2002 vol. 387 p. 108 - 116
ISSN:
0004-6361
Resumen:
We revise the fundamental parameters of the faint open cluster Hogg 15,
for which two recent colour-magnitude diagram (CMD) studies have
obtained significantly different ages. In the present study, we combine
a series of methods trying to constrain age, together with other
fundamental parameters. We employ spatial extractions to construct the
CMDs, and the cluster integrated spectrum to compare it with those of
templates of known age. We derive fundamental parameters, in particular,
distance, of the closely projected Wolf-Rayet star HDE 311884 (WR 47) -
often proposed to be physically related to Hogg 15. Based on the WR 47
spectrum and available photometry, we conclude that the short distance
implied by the Hipparcos parallax (216 pc) is affected by binary motion.
From the WR 47 spectrum we estimate a reddening E(B-V) and a distance of
1.10 +/- 0.05 and 5.2 +/- 0.9 kpc, respectively. For Hogg 15 we derive
an age of 20 +/- 10 Myr, a reddening of 1.10 +/- 0.05, and a distance of
3.1 +/- 0.5 kpc. We conclude that Hogg 15 is not related to WR 47 from
the point of view of origin, since the cluster and the star do not
belong to the same formation event.