Related papers: Post-processing the VLTI fringe-tracking data: Fir…
The ESO Very Large Telescope Interferometer (VLTI) is one of the leading interferometric facilities. It is equipped with several 8.2 and 1.8m telescopes, a large number of baselines up to 200m, and with several subsystems designed to enable…
Interferometric observations of stars in late stages of stellar evolution and the impact of VLTI observations are discussed. Special attention is paid to the spectral information that can be derived from these observations and on the…
Fringe tracking in interferometers is typically analyzed with the implicit assumption that there is a single phase associated with each telescope in the array. If the telescopes have apertures significantly larger than r0 and only partial…
The interferometric data processing methods that we describe in this paper use a number of innovative techniques. In particular, the implementation of the wavelet transform allows us to obtain a good immunity of the fringe processing to…
The VLTI Spectro Imager (VSI) was proposed as a second-generation instrument of the Very Large Telescope Interferometer providing the ESO community with spectrally-resolved, near-infrared images at angular resolutions down to 1.1…
The upgrade of the VLTI infrastructure for the 2nd generation instruments is now complete with the transformation of the laboratory, and installation of star separators on both the 1.8-m Auxiliary Telescopes (ATs) and the 8-m Unit…
FIRST (Fibered Imager foR a Single Telescope instrument) is a post-AO instrument that enables high contrast imaging and spectroscopy at spatial scales below the diffraction limit. FIRST achieves sensitivity and accuracy by a unique…
The use of integral field units is now commonplace at all major observatories offering efficient means of obtaining spectral as well as imaging information at the same time. IFU instrument designs are complex and spectral images have…
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…
I present a discussion of fundamental stellar parameters and their observational determination in the context of interferometric measurements with current and future optical/infrared interferometric facilities. Stellar parameters and the…
Interferometric measurements of optical path length differences of stars over large baselines can deliver extremely accurate astrometric data. The interferometer GRAVITY will simultaneously measure two objects in the field of view of the…
Context:Optical interferometry is at a key development stage. ESO's VLTI has established a stable, robust infrastructure for long-baseline interferometry for general astronomical observers. The present second-generation instruments offer a…
The 2nd generation VLTI instrument GRAVITY is a two-field infrared interferometer operating in the K band between 1.97 and 2.43 $\mu$m with either the four 8 m or the four 1.8 m telescopes of the Very Large Telescope (VLT). Beams collected…
An investigation of the stability of the transfer function of the European Southern Observatory's Very Large Telescope Interferometer has been carried out through observations of Fomalhaut over a wide range in hour angle. No significant…
PHASECam is the fringe tracker for the Large Binocular Telescope Interferometer (LBTI). It is a near-infrared camera which is used to measure both tip/tilt and fringe phase variations between the two adaptive optics (AO) corrected apertures…
Due to the recent dramatic technological advances, infrared interferometry can now be applied to new classes of objects, resulting in exciting new science prospects, for instance, in the area of high-mass star formation. Although…
Until now, the detailed interpretation of the observed microlensing events has suffered from the fact that the physical parameters of the phenomenon cannot be uniquely determined from the available astronomical measurements, i.e. the…
We present feasibility studies to directly image stellar surface features, which are caused by magnetic activity, with the Very Large Telescope Interferometer (VLTI). We concentrate on late type magnetically active stars, for which the…
Beginning in Fall 2018, the VERITAS high energy gamma-ray observatory (Amado, AZ) was upgraded to enable Stellar Intensity Interferometry (SII) observations during bright moon conditions. The system potentially allows VERITAS to spatially…
We present early results from the Faint InfraRed Extragalactic Survey (FIRES) at the VLT, the main goal of which is to study galaxy evolution in a deep, K-band selected sample. With our NIR selection, we select galaxies based on their…