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A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way
TLDR
Ten years of high-resolution astrometric imaging allow us to trace two-thirds of the orbit of the star currently closest to the compact radio source (and massive black-hole candidate) Sagittarius A* and show that the star is on a bound, highly elliptical keplerian orbit around Sgr A*. Expand
NAOS-CONICA first on sky results in a variety of observing modes
The Adaptive Optics NIR Instrument NAOS-CONICA has been commissioned at the VLT (UT4) between November 2001 and March 2002. After summarizing the observational capabilities of this multimodeExpand
Multiplicity of Nearby Free-floating Ultracool Dwarfs: A Hubble Space Telescope WFPC2 Search for Companions
We present Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) observations of a sample of 134 ultracool objects (spectral types later than M7) coming from the Deep Near InfraredExpand
THE ASTRALUX LARGE M-DWARF MULTIPLICITY SURVEY*
We present the results of an extensive high-resolution imaging survey of M-dwarf multiplicity using the Lucky Imaging technique. The survey made use of the AstraLux Norte camera at the Calar Alto 2.2Expand
A geometric distance measurement to the Galactic Center black hole with 0.3% uncertainty
We present a 0.16% precise and 0.27% accurate determination of R0, the distance to the Galactic Center. Our measurement uses the star S2 on its 16-year orbit around the massive black hole Sgr A* thatExpand
HST/NICMOS Imaging of Disks and Envelopes Around Very Young Stars
We present HST/NICMOS observations with ~ 0''.1 = 15 AU resolution of six young stellar objects in the Taurus star-formation region.
The Arches Cluster: Evidence for a Truncated Mass Function?*
We have analyzed high-resolution, adaptive optics HK observations of the Arches cluster obtained with NAOS-CONICA. With a spatial resolution of 84 mas, the cluster center is uniquely resolved. FromExpand
The mass function of the Arches cluster from Gemini adaptive optics data
We have analysed high resolution adaptive optics (AO) science demonstration data of the young, massive stellar cluster Arches near the Galactic Center, obtained with the Gemini North telescope inExpand
Binarity of transit host stars - Implications for planetary parameters
Context. Straight-forward derivation of planetary parameters can only be achieved in transiting planetary systems. However, planetary attributes such as radius and mass strongly depend on stellarExpand
THE LOW-MASS INITIAL MASS FUNCTION IN THE 30 DORADUS STARBURST CLUSTER
We present deep Hubble Space Telescope NICMOS 2 F160W band observations of the central 56 '' x 57 '' (14 pc x 14.25 pc) region around R136 in the starburst cluster 30Dor (NGC 2070) located in theExpand
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