Related papers: Prototyping liquid-crystal coronagraphs for exo-Ea…
Direct exo-Earth imaging is a key science goal for astronomy in the next decade. This ambitious task imposes a target contrast of ~10^-7 at wavelengths from I to J-band. In our prior study, we determined that polarization aberrations can…
Context. High contrast imaging has thoroughly combed through the limited search space accessible with first-generation ground-based adaptive optics instruments and the Hubble Space Telescope. Only a few objects were discovered, and many…
A discrete tomography method has been developed that is able to reconstruct three-dimensional coronal mass ejection (CME) density structure. We test the method by producing synthetic coronagraph imagery for three events using the…
We recently started to investigate how liquid-crystal on silicon (LCOS) spatial light modulator (SLM) would perform as programmable focal-plane phase mask (FPM) coronagraphs. Such "adaptive coronagraphs" could potentially help adapt to…
The next generation of ground-based instruments aims to break through the knowledge we have on exoplanets by imaging circumstellar environments always closer to the stars. However, direct imaging requires an AO system and high-contrast…
RISTRETTO is the evolution of the original idea of coupling the VLT instruments SPHERE and ESPRESSO \cite{lovis_2016a}, aiming at High Dispersion Coronagraphy. RISTRETTO is a visitor instrument that should enable the characterization of the…
Future space telescope coronagraph instruments hinge on the integration of high-performance masks and precise wavefront sensing and control techniques to create dark holes essential for exoplanet detection. Recent advancements in wavefront…
We have surveyed all conventional methods proposed or conceivable for obtaining resolved images of an Earth-like exoplanet. Generating a 10 x 10 pixel map of a 1 R_E world at 10 pc demands ~0.85 uas angular resolution and photon-collection…
We analyze the inner debris disk around $\epsilon$ Eridani using simulated observations with the Cool-Planet Imaging Coronagraph (CPI-C). Using the radiative transfer code MCFOST, we generate synthetic scattered-light images and spectral…
Direct imaging of protoplanetary disks promises to provide key insight into the complex sequence of processes by which planets are formed. However imaging the innermost region of such disks (a zone critical to planet formation) is…
Segmented telescopes are a possibility to enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the complexity of their aperture geometry, due to the central obstruction, support…
Discovering exoplanets in orbit around distant stars via direct imaging is fundamentally impeded by the combined effect of optical diffraction and photon shot noise under extreme star-planet contrast. Coronagraphs strive to increase the…
We describe the design and initial results from a visible-light Lyot coronagraph for SCExAO/VAMPIRES. The coronagraph is comprised of four hard-edged, partially transmissive focal plane masks with inner working angles of 36 mas, 55 mas, 92…
Direct imaging of extra-solar planets is now a reality, especially with the deployment and commissioning of the first generation of specialized ground-based instruments such as the Gemini Planet Imager and SPHERE. These systems will allow…
Habitable planets are often defined as terrestrial worlds capable of maintaining surface liquid water. As a result, atmospheric water vapor can be a critical indicator of habitability. Thus, habitability-themed exoplanet investigations…
Euclid is a space telescope currently developed in the framework of the ESA Cosmic Vision 2015-2025 Program. It addresses fundamental cosmological questions related to dark matter and dark energy. The lens system of one of the two…
Current and future high contrast imaging instruments aim to detect exoplanets at closer orbital separations, lower masses, and/or older ages than their predecessors, with the eventual goal of directly detecting terrestrial-mass…
Future large space- or ground-based telescopes will offer the resolution and sensitivity to probe the habitable zone of a large sample of nearby stars for exo-Earth imaging. To this end, such facilities are expected to be equipped with a…
Well over 700 exoplanets have been detected to date. Only a handful of these have been observed directly. Direct observation is extremely challenging due to the small separation and very large contrast involved. Imaging polarimetry offers a…
Coronagraphs allow for faint off-axis exoplanets to be observed, but are limited to angular separations greater than a few beam widths. Accessing closer-in separations would greatly increase the expected number of detectable planets, which…