相关论文: High angular resolution coronography for adaptive …
Context. Direct imaging of exoplanets takes advantage of state-of-the-art adaptive optics (AO) systems, coronagraphy, and post-processing techniques. Coronagraphs attenuate starlight to mitigate the unfavorable flux ratio between an…
The discovery of the exoplanet Proxima b highlights the potential for the coming generation of giant segmented mirror telescopes (GSMTs) to characterize terrestrial --- potentially habitable --- planets orbiting nearby stars with direct…
The vortex coronagraph is one of the most promising coronagraphs for high contrast imaging because of its simplicity, small inner working angle, high throughput, and clear off-axis discovery space. However, as with most coronagraphs,…
The need for high dynamic range imaging is crucial in many astronomical fields, such as extra-solar planet direct detection, extra-galactic science and circumstellar imaging. Using a high quality coronograph, dynamic ranges of up to…
NACO is the famous and versatile diffraction limited NIR imager and spectrograph with which ESO celebrated 10 years of Adaptive Optics at the VLT. Since two years a substantial effort has been put in to understanding and fixing issues that…
High contrast imaging is the primary path to the direct detection and characterization of Earth-like planets around solar-type stars; a cleverly designed internal coronagraph suppresses the light from the star, revealing the elusive…
Integral field spectrographs are major instruments to study the mechanisms involved in the formation and the evolution of early galaxies. When combined with multi-object spectroscopy, those spectrographs can behave as machines used to…
The WFIRST-AFTA 2.4 m telescope will provide in the next decade the opportunity to host a coronagraph for the imaging and spectroscopy of planets and disks. The telescope, however, is not ideal, given its obscured aperture. Only recently…
Optical beams and starlight distorted by atmospheric turbulence can be corrected with adaptive optics systems to enable efficient coupling into single-mode fibers. Deformable mirrors, used to flatten the wavefront in astronomical…
We describe results from the first astronomical adaptive optics system to use multiple laser guide stars, located at the 6.5-m MMT telescope in Arizona. Its initial operational mode, ground-layer adaptive optics (GLAO), provides uniform…
We propose a solution to the problem of astrometric and photometric calibration of coronagraphic images with a simple optical device which, in theory, is easy to use. Our design uses the Fraunhofer approximation of Fourier optics. Placing a…
High resolution spectroscopy made an important step ahead 10 years ago, leading for example to the discovery of numerous exoplanets. But the IR did not benefit from this improvement until very recently. CRIRES will provide a dramatic…
Adaptive optics is a strategy to compensate for sample-induced aberrations in microscopy applications. Generally, it requires the presence of "guide stars" in the sample to serve as localized reference targets. We describe an implementation…
The direct detection of extrasolar planets by imaging means is limited by the large flux of light from the host star being scattered into the region of interest by a variety of processes, including diffraction. Coronagraphs are devices that…
The capability of the adaptive optics to correct for the segmentation error is analyzed in terms of the residual wavefront RMS and the power spectral density of the phase. The analytical model and the end-to-end simulation give…
High-contrast imaging and spectroscopy provide unique constraints for exoplanet formation models as well as for planetary atmosphere models. Instrumentation techniques in this field have greatly improved over the last two decades, with the…
The far-field resolution of optical imaging systems is restricted by the Abbe diffraction limit, a direct result of the wave nature of light. One successful technological approach to circumventing this limit is to reduce the effective size…
The Habitable Exoplanet Imaging Mission (HabEx) concept requires an optical coronagraph that provides deep starlight suppression over a broad spectral bandwidth, high throughput for point sources at small angular separation, and…
We describe several projects addressing the growth of galaxies and massive black holes, for which adaptive optics is mandatory to reach high spatial resolution but is also a challenge due to the lack of guide stars and long integrations. In…
Coronagraph instruments on future space telescopes will enable the direct detection and characterization of Earth-like exoplanets around Sun-like stars for the first time. The quest for the optimal optical coronagraph designs has made rapid…