相关论文: Quasi Band-Limited Coronagraph for Extended Source…
This paper presents initial results from the ESA-funded ``SUPPPPRESS'' project, which aims to develop high-performance liquid-crystal coronagraphs for direct imaging of Earth-like exoplanets in reflected light. The project focuses on…
Axion-like particles (ALPs) have been searched for with a quasi-parallel stimulated resonant photon-photon collider sensitive to the sub-eV mass range by focusing two-color near-infrared pulse lasers into a vacuum. In this work, we have…
Stellar coronagraph performance is highly sensitive to optical aberrations. In order to effectively suppress starlight for exoplanet imaging applications, low-order wavefront aberrations entering a coronagraph such as tip-tilt, defocus and…
Direct imaging and spectroscopy of Earth-like planets and young Jupiters require contrasts up to 10^6-10^10 at angular separations of a few dozen milliarcseconds. To achieve this goal, one of the most promising approaches consists of using…
Coronagraphy is a very efficient technique for identifying and characterizing extra-solar planets orbiting in the habitable zone of their parent star, especially when used in a space environment. An important family of coronagraphs is based…
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…
We study the optimization of the Apodized Pupil Lyot Coronagraph (APLC) in the context of exoplanet imaging with ground-based telescopes. The APLC combines an apodization in the pupil plane with a small Lyot mask in the focal plane of the…
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…
Gaussian aperture pupil masks (GAPMs) can in theory achieve the contrast requisite for directly imaging an extrasolar planet. We use lab tests and simulations to further study their possible place as a high contrast imaging technique. We…
The ability to characterize exoplanets by spectroscopy of their atmospheres requires direct imaging techniques to isolate planet signal from the bright stellar glare. One of the limitations with the direct detection of exoplanets, either…
Direct observation of extra-solar planets (exoplanets) is essential to understand how planetary systems were born, how they evolve, and ultimately, to identify biological signatures on these planets. However, the enormous contrast in flux…
We have designed and built the first band-limited coronagraphic mask used for ground-based high-contrast imaging observations. The mask resides in the focal plane of the near-infrared camera PHARO at the Palomar Hale telescope and receives…
In the context of high dynamic range imaging, this study presents a breakthrough for the understanding of Apodized Pupil Lyot Coronagraphs, making them available for arbitrary aperture shapes. These new solutions find immediate application…
A next generation of space-based observatories aims to detect and characterize potentially Earth-like exoplanets around Sun-like stars using reflected light spectroscopy. However, it remains unclear how such direct imaging…
Coronagraphic techniques are required to detect exoplanets with future Extremely Large Telescopes. One concept, the Apodized Pupil Lyot Coronagraph (APLC), is combining an apodizer in the entrance aperture and a Lyot opaque mask in the…
The Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy (SCALES) is an instrument being designed to perform direct imaging of exoplanets in the mid-infrared (2-5 {\mu}m) with the Adaptive Optics System of W.M. Keck…
In recent years, new coronagraphic schemes have been proposed, the most promising being the optical vortex phase mask coronagraphs. In our work, a new scheme of broadband optical scalar vortex coronagraph is proposed and characterized…
We propose the application of coronagraphic techniques to the spectroscopic direct detection of exoplanets via the Doppler shift of planetary molecular lines. Even for an unresolved close-in planetary system, we show that the combination of…
Gaussian aperture pupil masks (GAPMs) can in theory achieve the contrast requisite for directly imaging an extrasolar planet. We outline the process of fabricating and testing a GAPM for use on the Penn State near-IR Imager and Spectrograph…
The EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) science mission concept uses a visible-wavelength Phase-Induced Amplitude Apodization (PIAA) coronagraph to enable high-contrast imaging of circumstellar debris systems…