Bibcode
Velasco, S.; Rebolo, R.; Oscoz, A.; Labadie, L.; Pérez-Garrido, A.
Referencia bibliográfica
Highlights on Spanish Astrophysics IX, Proceedings of the XII Scientific Meeting of the Spanish Astronomical Society held on July 18-22, 2016, in Bilbao, Spain, ISBN 978-84-606-8760-3. S. Arribas, A. Alonso-Herrero, F. Figueras, C. Hernández-Monteagudo, A. Sánchez-Lavega, S. Pérez-Hoyos (eds.), 2017 , p. 481-486
Fecha de publicación:
3
2017
Número de citas
0
Número de citas referidas
0
Descripción
The study of multiple systems and their link with the presence of discs
around their components is key to understanding the evolution of
low-mass pre-main sequence stars. Although there are indications that
high-multiplicity systems are much more frequent among very young stars,
until now, only a few of these young low-mass stellar systems have been
confirmed. Here, we present high spatial resolution i band imaging of
the system formed by LkHα 262 and LkHα 263, in the MBM12
cloud. It was obtained during the first commissioning period of the
Adaptive Optics Lucky Imager (AOLI) at the 4.2 m William Herschel
Telescope, using its Lucky Imaging mode. The multiple system LkHα
262/263 is composed of four low-mass very young M-type stars and some
discs, including an edge-on disc around LkHα 263C. The AOLI data
combined with previously available and newly obtained optical and
infrared imaging show that the three components of LkHα 263 are
co-moving, that there is orbital motion in the AB pair (0.41arcsec
separation), and, remarkably, that LkHα 262-263 is a common proper
motion system with a less than 1 mas/yr relative motion. According to
BT-settl models the mass of each of the five components is close to 0.4
M and the age is in the range 1-2 Myr. We also give marginal evidence of
a cooler companion to LkHα 262, at less than 0.15 arcsec, turning
LkHα 262-263 into a five-component likely gravitationally bounded
system. The presence of discs in some of the components offers an
interesting opportunity to investigate the formation and evolution of
discs in the early stages of multiple very low-mass systems.