相关论文: Astrometry Survey Missions Beyond the Magnitude Li…
We propose an extension of the GC3 streamer finding method of Johnston et al. 1996 that can be applied to the future Gaia database. The original method looks for streamers along great circles in the sky, our extension adds the kinematical…
GAIA is an astrometric satellite which has been approved by the European Space Agency for launch in about 2010. It will measure the angles between objects in fields that are separated on the sky by about a radian. Data will stream…
We use methods of differential astrometry to construct a small field inertial reference frame stable at the micro-arcsecond level. Such a high level of astrometric precision can be expected with the end-of-mission standard errors to be…
The Gaia data will help to improve the construction of a luminosity function for the disk and the halo and will provide a more accurate determination of the age of our solar neighborhood. Moreover, reliable stellar dynamical investigations…
A star enshrouded in a Dyson sphere with high covering fraction may manifest itself as an optically subluminous object with a spectrophotometric distance estimate significantly in excess of its parallax distance. Using this criterion, the…
We search for excess gamma-ray emission coincident with the positions of confirmed and candidate Milky Way satellite galaxies using 6 years of data from the Fermi Large Area Telescope (LAT). Our sample of 45 stellar systems includes 28…
Starting in 2013, Gaia will deliver highly accurate astrometric data, which eventually will supersede most other stellar catalogues in accuracy and completeness. It is, however, lim- ited to observations from magnitude 6 to 20 and will…
Background. Relative astrometry at or below the micro-arcsec level with a 1m class space telescope has been repeatedly proposed as a tool for exo-planet detection and characterization, as well as for several topics at the forefront of…
Precise cosmological measurements are essential for understanding the evolution of the universe and the nature of dark energy. The Five-hundred-meter Aperture Spherical Telescope (FAST), the most sensitive single-dish radio telescope, has…
We present the first high-precision proper motion catalog, tied to the International Celestial Reference System (ICRS), of infrared astrometric reference stars within R $\leq$ 25" (1 pc) of the central supermassive black hole at the…
High-precision astrometry at the sub-microarcsecond level opens up a window to study Earth-like planets in the habitable zones of Sun-like stars, and to determine their masses. It thus promises to play an important role in exoplanet science…
The reduced proper motion diagram (RPMD) for a complete sample of faint stars with high accuracy proper motions in the North Galactic Pole field SA57 is investigated. Eight stars with very large reduced proper motions are identified as…
Based on the astrometry and photometry in Gaia DR3, we identified new nearby white dwarfs and validated those that had been missed from recent white dwarf catalogues despite being previously documented. To ensure the reliability of their…
In this paper we present the Fermi All-sky Variability Analysis (FAVA), a tool to systematically study the variability of the gamma-ray sky measured by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. For each…
We present a wavelet-based algorithm to identify dwarf galaxies in the Milky Way in ${\it Gaia}$ DR2 data. Our algorithm detects overdensities in 4D position--proper motion space, making it the first search to explicitly use velocity…
Gaia Data Release 1 (Gaia DR1) contains astrometric results for more than 1 billion stars brighter than magnitude 20.7 based on observations collected by the Gaia satellite during the first 14 months of its operational phase. We give a…
Ultra-cool dwarfs are very low-mass stars or brown dwarfs and because of their faintness they are difficult targets for radial velocity and transit planet searches. High-precision astrometry is one way to efficiently discover planets around…
We investigate dwarf irregular(dIrr) galaxies as a new category of targets for indirect Dark Matter(DM) searches with gamma-rays. In the framework of point-like analysis, dwarf spheroidal(dSph) galaxies are usually considered as one of the…
Context. White dwarfs can be used to study the structure and evolution of the Galaxy by analysing their luminosity function and initial mass function. Among them, the very cool white dwarfs provide the information for the early ages of each…
We present GaiaHub, a publicly available tool that combines $Gaia$ measurements with $Hubble$ $Space$ $Telescope$ ($HST$) archival images to derive proper motions (PMs). It increases the scientific impact of both observatories beyond their…