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We report the outcome of a deep multi-wavelength study of the IC2391 young open cluster. We aim at uncovering new low-mass and sub-stellar members of the cluster and identifying new debris disk objects. A 30*30 square arcmin area in IC 2391 was observed using the wide-field imager at the ESO 2.2m telescope. The completeness limits of the photometry at 3 sigma level are V=24.7, Rc=23.7 and Ic=23.0, faint enough to reveal sub-stellar members down to about 0.03 solar masses. Our membership criteria are based on the use of our optical data, in combination with JHKs magnitudes from the 2MASS catalog. We also estimate the physical parameters of the selected candidates. Debris disk candidates are identified on the basis of their infrared excess emission using near- and mid-infrared photometry from the Spitzer Space Telescope. Our optical survey, which has a limiting magnitude at 3 sigma level 1-2 mag fainter than previous optical surveys conducted in IC2391, revealed 29 new low-mass member candidates of the cluster. We estimate the contamination to be at least 50%. We constrain the fraction of sub-stellar objects in the range 8-15% and discuss possible explanations for the deficit of brown dwarfs in this cluster. We also identified 10 candidates in the cluster showing IR excess emission consistent with the presence of debris disks.
We present a deep survey of the young southern cluster IC2391. We have covered 2 sq. degrees in the R,I filter. We have selected several dozens VLM stars and BD candidates based on the position of these objects in the Color-Magnitude Diagram.
We aim to test a purely photometric approach to statistically identify a young clustered population embedded in a large population of field stars, with no prior knowledge on the nature of stars in the field. We conducted our blind test study on the N
Galactic open clusters have been long recognized as one of the best tools to investigate the chemical content of Galactic disk and its time evolution. In the last decade, many efforts have been directed to chemically characterize the old and intermed
Son Of X-Shooter (SOXS) will be a new instrument designed to be mounted at the Nasmyth--A focus of the ESO 3.5 m New Technology Telescope in La Silla site (Chile). SOXS is composed of two high-efficiency spectrographs with a resolution slit product 4
WISE J085510.83-071442.5 (hereafter, WISE 0855-07) is the coolest Y dwarf known to date and is located at a distance of 2.31$pm 0.08$ pc, giving it the fourth largest parallax of any known star or brown dwarf system. We report deep $z$-band observati