ICATE   21876
INSTITUTO DE CIENCIAS ASTRONOMICAS, DE LA TIERRA Y DEL ESPACIO
Unidad Ejecutora - UE
artículos
Título:
Dynamical detection of three triple stellar systems in open clusters
Autor/es:
GONZÁLEZ, J.F.; VERAMENDI, M. E.; COWLEY, C. R.
Revista:
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2014 vol. 443 p. 1523 - 1531
ISSN:
0035-8711
Resumen:
We present a kinematic analysis of three triple stellar systems
belonging to two open clusters: CPD-60°961 and HD 66137 in NGC 2516,
and HD 315031 in NGC 6530. All three systems are hierarchical triples
with a close binary bound to a third body in a wider orbit, whose
presence is detected through velocity variations of the close binary
barycentre. Orbital parameters are derived from radial velocity curves.
Absolute parameters for all stars are estimated assuming cluster
membership. Some dynamical and evolutionary aspects of these systems are
discussed, particularly the possible influence of Kozai cycles. The two
systems of NGC 2516 have similar orbital configurations with inner
periods of 11.23 and 8.70 d and outer periods of 9.79 and 9.24 yr. The
young system HD 315031 in the cluster NGC 6530 has an inner binary with
a period of 1.37 d and a very eccentric (e = 0.85) outer orbit with a
period of 483 d. We report also radial velocity measurements of the
components of the visual binary CPD-60°944 in NGC 2516. Including
results from previous works, this cluster would harbour five
hierarchical triples. Possible dynamical evolutionary scenarios are
discussed. Long-term radial velocity monitoring is highlighted as
strategy for the detection of subsystems with intermediate separations,
which are hard to cover with normal spectroscopic studies or visual
techniques.