Related papers: A Multi-wavelength Differential Imaging Experiment…

Cross-correlating the data of neutral hydrogen (HI) 21cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information. In this work, we investigate the cross-correlation of MeerKAT…

The detection and characterization of Earth-like exoplanets is one of the major science drivers for the next generation of telescopes. Current direct imaging instruments are limited by evolving non-common path aberrations (NCPAs). The NCPAs…

The Habitable Worlds Observatory requires active speckle suppression to directly image Earth-like exoplanets. Focal plane wavefront sensing and control allows us to detect, and subsequently remove, time-varying speckles through measurements…

Future missions such as Solar Orbiter (SO), InterHelioprobe, or Solar Probe aim at approaching the Sun closer than ever before, with on board some high resolution imagers (HRI) having a subsecond cadence and a pixel area of about $(80km)^2$…

One of the key science goals for extremely large telescopes (ELTs) is the detailed characterization of already known directly imaged exoplanets. The typical adaptive optics (AO) Nyquist control region for ELTs is ~0.4 arcseconds, placing…

Deformable mirrors (DMs) are a critical technology to enable coronagraphic direct imaging of exoplanets with current and planned ground - and space-based telescopes as well as future mission concepts that aim to image exoplanet types…

Context: NOTT (formerly Hi-5) is a new high-contrast L' band (3.5-4.0 \textmu m) beam combiner for the VLTI with the ambitious goal to be sensitive to young giant exoplanets down to 5 mas separation around nearby stars. The performance of…

Imaging terrestrial exoplanets around nearby stars is a formidable technical challenge, requiring the development of coronagraphs to suppress the stellar halo of diffracted light at the location of the planet. In this review, we derive the…

Non-common path quasi-static and differential aberrations are one of the big hurdles of direct imaging for current and future high-contrast imaging instruments. They increase speckle and photon noise thus reducing the achievable contrast…

Angular differential imaging is a high-contrast imaging technique that reduces quasi-static speckle noise and facilitates the detection of nearby companions. A sequence of images is acquired with an altitude/azimuth telescope while the…

Specific high contrast imaging instruments are mandatory to characterize circumstellar disks and exoplanets around nearby stars. Coronagraphs are commonly used in these facilities to reject the diffracted light of an observed star and…

Spectral differential imaging (SDI) is part of the observing strategy of current and on-going high-contrast imaging instruments on ground-based telescopes. Although it improves the star light rejection, SDI attenuates the signature of…

In a standard computed tomography (CT) image, pixels having the same Hounsfield Units (HU) can correspond to different materials and it is, therefore, challenging to differentiate and quantify materials. Dual-energy CT (DECT) is desirable…

The correction of quasi-static wavefront errors within a coronagraphic optical system will be a key challenge to overcome in order to directly image exoplanets in reflected light. These quasi-static errors are caused by mid to high-order…

To image faint substellar companions obscured by the stellar halo and speckles, scattered light from the bright primary star must be removed in hardware or software. We apply the "locally-optimized combination of images" (LOCI) algorithm to…

The evanescent wave coronagraph uses the principle of frustrated total internal reflection (FTIR) to suppress the light coming from the star and study its close environment. Its focal plane mask is composed of a lens and a prism placed in…

In Spring 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its $\sim$130-night campaign from the Large Binocular Telescope (LBT) atop Mt Graham, Arizona. This survey benefits from the many technological achievements of the…

Described here is the design and commissioning of a coronagraph facility for the 4.2 metre William Herschel Telescope (WHT) and its Nasmyth Adaptive Optics system for Multi-purpose Instrumentation (NAOMI). The use of the NAOMI system gives…

The Near-Infrared Coronagraphic Imager (NICI) is a high-contrast AO imager at the Gemini South telescope. The camera includes a coronagraphic mask and dual channel imaging for Spectral Differential Imaging (SDI). The instrument can also be…

In this paper, we present an original observational approach, which combines, for the first time, traditional speckle imaging with image post-processing to obtain in the optical domain diffraction-limited images with high contrast (1e-5)…