相关论文: Relative astrometry in an annular field

High precision astrometry aims at source position determination to a very small fraction of the diffraction image size, in high SNR regime. One of the key limitations to such goal is the optical response variation of the telescope over a…

The Closeby Habitable Exoplanet Survey (CHES) aims to achieve microarcsecond-level astrometry of about one hundred nearby FGK-type stars within 10 parsecs to detect Earth-like planets. Such precision exceeds the capability of absolute…

We investigate the limits of ground-based astrometry with adaptive optics using the core of the Galactic globular cluster M5. Adaptive optics systems provide near diffraction-limit imaging with the world's largest telescopes. The…

Space astrometry is capable of sub-microarcsecond measurements of star positions. A hundred visits over several years could yield relative astrometric precision of ~0.1 uas, below the astrometric signature (0.3 uas) of a Sun-Earth system at…

Radio wavelength astrometry of stars and other objects has a long and productive history. The use of that technique to determine whether stars have planets around them would cover a nearly unique part of the parameter space for detection of…

The high accuracy of modern space astrometry requires the use of General Relativity to model the propagation of stellar light through the gravitational field encountered from a source to a given observer inside the Solar System. In this…

Cosmology with large interferometric telescopes is a rich and largely unexplored subject, involving three types of measurement: astrometric measurement of absolute distances and proper motions, dispersions of relative proper motions, and…

With the advent of optical interferometers that will be coming online in the next decade, radial velocity searches for extra-solar planets will be complemented by high angular resolution astrometric measurements. In this paper, we explore…

This paper is devoted to a practical model for relativistic reduction of positional observations with an accuracy of 1 \muas which is expected to be attained in the future space astrometry missions. All relativistic effects which are caused…

For microlensing case angular distances between images or typical astrometric shifts due to microlensing are about $10^{-5}-10^{-6} \mu as$. Such an angular resolution will be reached with the space space--ground interferometer Radioastron.…

I present a review of astrometric techniques and instrumentation utilized to search for, detect, and characterize extra-solar planets. First, I briefly summarize the properties of the present-day sample of extrasolar planets, in connection…

The Galactic center offers us a unique opportunity to test General Relativity (GR) with the orbits of stars around a supermassive black hole. Observations of these stars have been one of the great successes of adaptive optics on 8-10 m…

Because of the recent technological advances, the key technologies needed for precision space optical astrometry are now in hand. The Microarcsecond Astrometry Probe (MAP) mission concept is designed to find 1 Earth mass planets at 1AU…

Large ground-based telescopes equipped with adaptive optics (AO) systems have ushered in a new era of high-resolution infrared photometry and astrometry. Relative astrometric accuracies of <0.2 mas have already been demonstrated from…

Microarcsecond (uas) astrometry is an indispensable technique to detect earth-like exoplanets, fully characterize exoplanetary orbits, and measure their masses --information critical for assessing their habitability. Highly accurate…

To explore capabilities of moderate-size optical telescopes in surveys, the set of 9 new wide-field designs having apertures up to 1 m is considered. All but one systems have angular field of view in a range 3.5-10 degrees and flat focal…

Astronomers working with faint targets will benefit greatly from improved image quality on current and planned ground-based telescopes. At present, most adaptive optic systems are targeted at the highest resolution with bright guide stars.…

We analyze photometric observations of stars, which experienced microlensing events at the considered time, in order to compare the efficiency of detecting exoplanets in observations performed at thirteen different telescopes and with…

High-contrast imaging observations of large angular diameter stars enable complementary science questions to be addressed compared to the baseline goals of proposed missions like the Terrestrial Planet Finder-Coronagraph, New World's…

Astrometry provides the foundation for astrophysics. Accurate positions are required for the association of sources detected at different times or wavelengths, and distances are essential to estimate the size, luminosity, mass, and ages of…