Related papers: Probing the Upper Scorpius mass function in the pl…

Two eclipsing binaries in the USco association have recently yielded precise values of masses and radii for 4 low-mass members of the association. Standard evolution models would require these dM4.5 - dM5 stars to have ages which are…

We report the initial results of a VLT/NACO high spatial resolution imaging survey for multiple systems among 58 M-type members of the nearby Upper Scorpius OB association. Nine pairs with separations below 100 have been resolved. Their…

Giant planets are usually thought to form within a few tens of AU of their host stars, and hence it came as a surprise when we found what appeared to be a planetary mass (~0.008 Msun) companion around the 5 Myr-old solar mass star 1RXS…

We report the detection of seven low mass companions to intermediate-mass stars (SpT B/A/F; $M$$\approx$1.5-4.5 solar masses) in the Scorpius-Centaurus Association using nonredundant aperture masking interferometry. Our newly detected…

The improved astrometry precision of Gaia-eDR3 allows us to perform a detailed study of the Upper Scorpius OB association and revisit its spatial, kinematic, and age substructure. We achieve this by combining clustering techniques and…

We combine results from imaging searches for substellar objects in the sigma Orionis cluster and follow-up photometric and spectroscopic observations to derive a census of the brown dwarf population in a region of 847 arcmin^2. We identify…

The Upper-Scorpius association (5-11 Myr) contains a unique population of low-mass (M<30 MJup) brown-dwarfs. The detailed relative characterization of their physical properties (mass, radius, temperature, composition, ongoing accretion)…

We present ALMA Band 7 continuum (340 GHz) and CO J=3-2 observations for an extended sample of disks in the Upper Scorpius OB Association (Upper Sco, age ~ 10 Myr). The targets were selected from previous studies that identified new members…

We present deep 1.2 millimeter photometry of 37 stars in the young (5 Myr) Upper Scorpius OB association, sensitive to ~4 x 10^-3 Mjup of cool millimeter dust. Disks around four low- and solar-mass stars are detected, as well as one debris…

Here we present the results of a wide-field (~36 sq. deg.) near-infrared (ZYJHK) survey of the Praesepe cluster using the Data Release 9 of the UKIRT Infrared Deep Sky Survey Galactic Clusters Survey. We selected cluster candidates of…

Proper motion measurements of the cool and ultracool populations in the Upper Scorpius OB association are crucial to confirm membership and to identify possible run-away objects. We cross-match samples of photometrically selected and…

We present a deep I,Z photometric survey covering a total area of 1.12 deg^{2} of the Sigma Orionis cluster (Icompl=22 and Zcompl=21.5mag). From I, I-Z color-magnitude diagrams we have selected 153 candidates that fit the previously known…

We report the discovery of a new low-mass spectroscopic (SB2) stellar binary system in the star-forming region of Upper Scorpius. This object, UScoCTIO5, was discovered by Ardila (2000), who assigned it a spectral class of M4. A KeckI HIRES…

A key outstanding question in star and planet formation is how far the initial mass function of stars and sub-stellar objects extends, and whether or not there is a cut-off at the very lowest masses. Isolated objects in the planetary-mass…

Using images taken with the Dark Energy Camera (DECam), the first extensive survey of low mass and substellar objects is made in the 15-20 Myr Upper Centaurus Lupus (UCL) and Lower Centaurus Crux (LCC) subgroups of the Scorpius Centaurus OB…

Presented are the results of a large and deep optical-near-infrared multi-epoch survey of the Praesepe open star cluster using data from the UKIDSS Galactic Clusters Survey. Multiple colour magnitude diagrams were used to select potential…

We study X-ray emission from young stars by analyzing deep XMM-Newton observations of two regions of the Upper Scorpius association, having an age of 5 Myr. Based on near infrared and optical photometry we identify 22 Upper Scorpius…

SONYC - Substellar Objects in Nearby Young Clusters - is a survey program to investigate the frequency and properties of substellar objects with masses down to a few times that of Jupiter in nearby star-forming regions. For the ~1Myr old…

We present measurements of key protoplanetary disk properties inferred from parametric models of ALMA 12CO spectral line visibilities. We derive gas-disk radii, integrated fluxes, optically thick emission layers, and brightness temperature…

We present the results of a survey to detect low-mass companions of UMa group members, carried out in 2003-2006 with NACO at the ESO VLT. While many extra-solar planets and planetary candidates have been found in close orbits around stars…