INVESTIGADORES
GONZALEZ Jorge Federico
artículos
Título:
Spectroscopic Binaries and Kinematic Membership in the Open Cluster NGC 3532
Autor/es:
GONZÁLEZ, J. F.; LAPASSET, E.
Revista:
ASTRONOMICAL JOURNAL
Editorial:
American Astronomical Society - IOP
Referencias:
Año: 2002 vol. 123 p. 3318 - 3324
ISSN:
0004-6256
Resumen:
We report spectroscopic observations for bright stars in the open
cluster NGC 3532 up to 1 mag below the turnoff point. We compute radial
velocities by cross-correlations and determine spectral types and
rotational velocities. Using 21 stars identified as certain members, we
derive a mean cluster velocity of +3.4+/-0.3 km s-1. From
radial velocities and angular distances to the cluster center, we
compute membership probabilities for all but two stars that are radial
velocity variables. Only one out of 34 program stars is a clear
kinematic nonmember. Three spectroscopic binaries and three additional
possible radial velocity variables are detected among the 23 stars
measured more than once. We report the star HD 96609 as a double-lined
spectroscopic binary. Using the two-dimensional cross-correlation
technique TODCOR developed by Zucker & Mazeh, we derive the radial
velocity curves for both components and obtain the orbital parameters
with errors of 0.3% and 0.7% for the projected orbital semiaxis and
masses, respectively. This system is composed of two main-sequence stars
in a circular orbit, with a period of 8.19 days. The observations
presented here were obtained at the Complejo Astronómico El
Leoncito (CASLEO), which is operated under agreement between the Consejo
Nacional de Investigaciones Científicas y Técnicas de la
República Argentina (CONICET) and the National Universities of La
Plata, Córdoba, and San Juan.