Related papers: Orbit of the young very low-mass spectroscopic bin…
The very young brown dwarf candidate ChaHa8 was recently discovered to have a close (~1AU) companion by means of radial velocity monitoring. We present additional radial velocity data obtained with UVES/VLT between 2007 and 2010, which…
We present results of a radial velocity (RV) survey for planets and brown dwarf (BD) companions to very young BDs and (very) low-mass stars (VLMSs) in ChaI. High-resolution echelle spectra of ChaHa1-8 and 12 (M6-M8), and B34, CHXR74, Sz23…
I review here the results of the first RV survey for spectroscopic companions to very young brown dwarfs (BDs) and (very) low-mass stars in the ChaI star-forming cloud with UVES at the VLT. This survey studies the binary fraction in an as…
We report the discovery of a 16-20 Jupiter mass radial velocity companion around the very young (3 Myr) brown dwarf candidate ChaHa8. Based on high-resolution echelle spectra of ChaHa8 taken between 2000 and 2007 with UVES at the VLT, a…
Given that secular perturbations in a binary system not only excite high orbital eccentricities but also alter the planetary orbital inclination, the classical Keplerian orbital model is no longer applicable for orbital retrieval. The…
Since a majority of young low-mass stars are members of multiple systems, the study of their stellar and disk configurations is crucial to our understanding of both star and planet formation processes. Here we present near-infrared adaptive…
We have carried out a radial velocity (RV) search for planets and brown dwarf companions to very young (1-10Myr) brown dwarfs and very low-mass stars in the ChaI star forming region. This survey has been carried out with the high-resolution…
The star-forming regions in Chamaeleon are one of the nearest (distance ~165 pc) and youngest (age ~2 Myrs) conglomerates of recently formed stars and the ideal target for population studies of star formation. We investigate a total of 16…
Searches for companions of brown dwarfs by direct imaging mainly probe orbital separations > 3-10 AU. On the other hand, previous radial velocity surveys of brown dwarfs are mainly sensitive to separations smaller than 0.6 AU. It has been…
We report the discovery of a 16-20 Jupiter mass radial velocity companion around the very young (~3 Myr) brown dwarf candidate ChaHa8 (M5.75-M6.5). Based on high-resolution echelle spectra of ChaHa8 taken between 2000 and 2007 with UVES at…
We report the detection of a very low mass star (VLMS) companion to the primary star 1SWASPJ234318.41+295556.5A (J2343+29A), using radial velocity (RV) measurements from the PARAS (PRL Advanced Radial-velocity Abu-sky Search) high…
A severe problem of the research in star-formation is that the masses of young stars are almost always estimated only from evolutionary tracks. Since the tracks published by different groups differ, it is often only possible to give a rough…
We obtained new spectra of Kepler-34 and Kepler-35 with Keck-HIRES, nearly a decade after these systems were originally characterized with this spectrograph and other instruments, to search for RV trends from a potential third stellar-mass…
We report the discovery of a new short-period pre-main-sequence eclipsing binary, RX Gru, orbited by a distant circumbinary companion. We characterized the system by analysing the photometric observations from the Solaris network, the…
Context: Most stars in the galactic stellar population are low-mass stars. Very low-mass (VLM) stars are a subset of the low-mass stars typically defined in terms of the stellar masses ranging from 0.6 M_sun to the hydrogen-burning limit of…
We report orbital parameters for two low-mass, pre-main sequence, double-lined spectroscopic binaries VSB 111 and VSB 126. These systems were originally identified as single-lined on the basis of visible-light observations. We obtained…
We report the confirmation of the binary nature of the nearby, very low-mass system NLTT 33370 with adaptive optics imaging and present resolved near-infrared photometry and integrated light optical and near-infrared spectroscopy to…
Characterizing multiplicity in the very low mass (VLM) domain is a topic of much current interest and fundamental importance. Here we report on a near-IR AO imaging survey of 31 young brown dwarfs and VLM stars, 28 of which are in…
We have obtained high contrast images of four nearby, faint, and very low mass objects 2MASSJ04351455-1414468, SDSSJ044337.61+000205.1, 2MASSJ06085283-2753583 and 2MASSJ06524851-5741376 (here after 2MASS0435-14, SDSS0443+00, 2MASS0608-27…
We present Adaptive Optics-aided speckle observations of 47 young stars in the $\epsilon$ Cha association, made at the 4-m Southern Astrophysical Research Telescope in the $I$-band. We resolved 10 new binary pairs, 5 previously known…