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The Brown Dwarf Kinematics Project (BDKP. III. Parallaxes for 70 Ultracool Dwarfs
We report parallax measurements for 70 ultracool dwarfs (UCDs) including 11 late-M, 32 L, and 27 T dwarfs. In this sample, 14 M and L dwarfs exhibit low surface gravity features, 6 are close binary
The Intrinsic Colors of RR Lyrae Variables: A Means to Determine Interstellar Reddening
ABSTRACT We present refined BVI light curves for six field RR Lyrae variable stars. The refinements include new data and improved photometric calibration compared to our previous work. For each star,
Infrared aperture photometry at ESO (1983-1994) and its future use.
We describe the infrared (IR) photometric system for the single channel photometers at ESO, which have been used from 1983 until 1994. In addition to the broadband near infrared (NIR, 1 5 m)
On the difference between nuclear and contraction ages
Context. Ages derived from low mass stars still contracting onto the main sequence often differ from ages derived from the high mass ones that have already evolved away from it. Aims. We investigate
HD 34700 is a T Tauri multiple system
We have imaged the young double-lined spectroscopic binary HD 34700 in the near-infrared and find evidence for two faint, visual, stellar components at 5$\farcs$2 and 9$\farcs$2 distance.
Evolution of young brown dwarf disks in the mid-infrared
We have imaged two bona-fide brown dwarfs with TReCS/GEMINI-S and find mid-infrared excess emission that can be explained by optically thick dust disk models. In the case of the young ( ≈ 2 Myr) Cha
Grain growth and dust settling in a brown dwarf disk - Gemini/T-ReCS observations of CFHT-BD-Tau 4
We present accurate mid-infrared observations of the disk around the young, bona fide brown dwarf CFHT-BD-Tau 4. We report GEMINI/T-ReCS measurements in the 7.9, 10.4 and 12.3 µm filters, from which
Identification of a Wide, Low-Mass Multiple System Containing the Brown Dwarf 2MASS J0850359+105716
NLTT 20346/2MASS J0850+1057 joins a growing list of hierarchical systems containing brown dwarf binaries and is among the lowest binding energy associations found in the field.
Vega: smaller grains in a larger shell
We have re-analysed the IRAS pointed observations of Vega. We find that the 60 μm emission of Vega is as extended as 35±5 arcsec. This is much larger than the generally accepted 23 arcsec (Aumann et