Related papers: Astrometry with Extended-Path Intensity Correlatio…
Measurements of the spectrum of the fluctuations of the output current of the quadratic detector of a telescope can be used to find unresolved astronomical gravitational lenses and determine time delays between their image components. These…
The Extrasolar Planet Search with PRIMA project (ESPRI) aims at characterising and detecting extrasolar planets by measuring the host star's reflex motion using the narrow-angle astrometry capability of the PRIMA facility at the Very Large…
Aims. This article aims to provide an alternative method of measuring the porosity of multi-phase composite ices from their refractive indices and of characterising how the abundance of a premixed contaminant (e.g., CO2) affects the…
Opacity is a property of many plasmas, and it is normally expected that if an emission line in a plasma becomes optically thick, its intensity ratio to that of another transition that remains optically thin should decrease. However,…
An extension may be proposed to the intensity interferometer of Hanbury Brown and Twiss to provide the Fourier phase measurement by the use of third-order intensity correlations. It is well known that interferometric reconstruction of…
Accurate astrometry and photometry of saturated and coronagraphic point spread functions (PSFs) are fundamental to both ground- and space-based high contrast imaging projects. For ground-based adaptive optics imaging, differential…
The direct observation of cold and temperate planets within 1 to 10 AU would be extremely valuable for uncovering their atmospheric compositions but remains a formidable challenge with current astronomical methods. Ground-based optical…
With the discovery of the first transiting extrasolar planetary system back to 1999, a great number of projects started to hunt for other similar systems. Because of the incidence rate of such systems was unknown and the length of the…
We consider the issue of validating the relationship between electric fields and optical intensity as proposed by the classical theory of electromagnetism. We describe an interference scenario in which this can be checked using only…
Orbital solutions for binary or multiple stellar systems that combine astrometry (e.g., position angles and angular separations) with spectroscopy (radial velocities) have important advantages over astrometric-only or spectroscopic-only…
The line intensity mapping technique involves measuring the cumulative emission from specific spectral lines emitted by galaxies and intergalactic gas. This method provides a way to study the matter distribution and the evolution of…
We demonstrate the ability to measure precise stellar barycentric radial velocities with the dispersed fixed-delay interferometer technique using the Exoplanet Tracker (ET), an instrument primarily designed for precision differential…
Having a need to perform differential photometry for tens of thousands stars in a several square degrees field, we developed Astrokit program. The software corrects the star brightness variations caused by variations of atmospheric…
Nearby interstellar clouds at high Galactic latitudes are ideal objects in which the interaction of interstellar dust with photons from the well-characterized interstellar radiation field can be studied. Scattering and UV-excited…
A major goal of modern astrophysics is to understand the processes by which the universe evolved from its initial simplicity, as seen in measurements of the Cosmic Microwave Background, to the universe we see today, with complexity on all…
High angular resolution observations at optical wavelengths provide valuable insights in stellar astrophysics, directly measuring fundamental stellar parameters, and probing stellar atmospheres, circumstellar disks, elongation of rapidly…
Direct exoplanet spectroscopy aims to measure the spectrum of an exoplanet while simultaneously minimizing the light collected from its host star. Isolating the planet light from the starlight improves the signal-to-noise ratio (S/N) per…
An important topic of interest in imaging is the construction of protocols that are not diffraction limited. This can be achieved in a variety of ways, including classical superresolution techniques or quantum entanglement-based protocols.…
Aims: In this work, we discuss a way to combine High Dispersion Spectroscopy and High Contrast Imaging (HDS+HCI). For a planet located at a resolvable angular distance from its host star, the starlight can be reduced up to several orders of…
Proper photometric data are challenging to obtain in the K2 mission of the Kepler space telescope due to strong systematics caused by the two-wheel-mode operation. It is especially true for variable stars wherein physical phenomena occur on…