A&A 399, 113-120 (2003)
DOI: 10.1051/0004-6361:20021920
Ruprecht 3: An old star cluster remnant?
D. B. Pavani1, E. Bica1, A. V. Ahumada2 and J. J. Clariá21 Universidade Federal do Rio Grande do Sul, IF, CP 15051, Porto Alegre 01501-970, RS, Brasil
2 Observatorio Astronómico de Córdoba, Laprida, 854, 5000, Córdoba, Argentina
e-mail: andrea@mail.oac.uncor.edu; claria@mail.oac.uncor.edu
(Received 14 October 2002 / Accepted 20 November 2002)
Abstract
2MASS
J and
H photometry and integrated spectroscopy are
employed to study the nature of the poorly populated compact concentration of
stars Ruprecht 3, which was previously catalogued as an open cluster. The
integrated spectrum remarkably resembles that of a moderately metal-rich
globular cluster. The distribution of the object stars in the
colour-magnitude diagram is compatible with that of a
Gyr open
cluster or older, depending on whether the bluer stars are interpreted as
turnoff stars or blue stragglers, respectively. We derive for the
object a distance from the Sun
kpc and a
colour excess
E(B-V) = 0.04.
Although a globular cluster remnant cannot be ruled out, the
integrated spectrum resemblance to that of a globular cluster probably
reflects a stochastic effect owing to the few brighter stars. The structural
and photometric properties of Ruprecht 3 are compatible with what would
be expected for an intermediate-age open cluster remnant.
Key words: Galaxy: open clusters and stellar associations: general -- open clusters and associations: individual: Ruprecht 3 -- methods: observational -- techniques: spectroscopic
Offprint request: D. B. Pavani, dpavani@if.ufrgs.br
SIMBAD Objects
© ESO 2003

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