Related papers: Reaching micro-arcsecond astrometry with long base…
Spectrographs nominally contain a degree of quasi-static optical aberrations resulting from the quality of manufactured component surfaces, imperfect alignment, design residuals, thermal effects, and other other associated phenomena…
The Large Binocular Telescope Interferometer is a high contrast imager and interferometer that sits at the combined bent Gregorian focus of the LBT's dual 8.4~m apertures. The interferometric science drivers dictate 0.1'' resolution with…
A derivation of the optical axis lenght fluctations due by tilts of the mirrors of the Fabry-Perot cavity of long-baseline interferometers for the detection of gravitational waves in presence of the gravitational field of the earth is…
Doppler orbitography uses the Doppler shift in a transmitted signal to determine the orbital parameters of satellites including range and range-rate (or radial velocity). We describe two techniques for atmospheric-limited optical Doppler…
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…
Astrometry is one of the main science case which drives the requirements of the next multiconjugate adaptive optics (MCAO) systems for future extremely large telescopes. The small diffraction limited point-spread function (PSF) and the high…
We describe a new method which achieves high precision Very Long Baseline Interferometry (VLBI) astrometry in observations at millimeter wavelengths. It combines fast frequency-switching observations, to correct for the dominant…
The conventional approach to high-precision narrow-angle astrometry using a long baseline interferometer is to directly measure the fringe packet separation of a target and a nearby reference star. This is done by means of a technique known…
Gravimetry typically lacks the resolution to measure single microdroplets, whereas microscopy is often inaccurate beyond the resolution limit. To address these issues, we advance and integrate these complementary methods, introducing…
The ionospheric path delay impacts single-band very long baseline interferometry (VLBI) group delays, which limits their applicability for absolute astrometry. I consider two important cases: when observations are made simultaneously at two…
The GRAVITY instrument has been revolutionary for near-infrared interferometry by pushing sensitivity and precision to previously unknown limits. With the upgrade of GRAVITY and the Very Large Telescope Interferometer (VLTI) in GRAVITY+,…
The basic effect of the earth's atmospheric refraction on telescope operation is the reduction of the true zenith angle to the apparent zenith angle, associated with prismatic aberrations due to the dispersion in air. If one attempts…
This paper discusses new Fundamental physics experiment that will test relativistic gravity at the accuracy better than the effects of the second order in the gravitational field strength, ~G^2. The Laser Astrometric Test Of Relativity…
Context. For accurately measuring intensities and determining magnetic field strengths of small-scale solar (magnetic) structure, knowledge of and compensation for the point spread function is crucial. For images recorded with the Swedish…
MICADO is the Multi-AO Imaging Camera for Deep Observations, and it will be one of the first light instruments of the Extremely Large Telescope (ELT). Doing high precision multi-object differential astrometry behind ELT is particularly…
GRAVITY+ improves by orders of magnitude the sensitivity, sky-coverage and contrast of the Very Large Telescope Interferometer (VLTI). A central part of this project is the development of Gravity Plus Adaptive Optics (GPAO), a dedicated…
The Very Large Telescope Interferometer is one of the most proficient observatories in the world for high angular resolution. Since its first observations, it has hosted several interferometric instruments operating in various bandwidths in…
Intensity interferometry permits very long optical baselines and the observation of sub-milliarcsecond structures. Using planned kilometric arrays of air Cherenkov telescopes at short wavelengths, intensity interferometry may increase the…
Context: In recent years, stellar intensity interferometry has seen renewed interest from the astronomical community because it can be efficiently applied to Cherenkov telescope arrays. Aims: We have investigated the accuracy that can be…
We give an introduction to interferometrical concepts and their applicability to Be stars. The first part of the paper concentrates on a short historic overview and basic principles of two-beam interferometric observations. In the second…