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Related papers: A Coronagraph with a Sub-$\lambda/D$ IWA and a Mod…

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To detect Earth-like planets in the visible with a coronagraphic telescope, two major noise sources have to be overcome: the photon noise of the diffracted star light, and the speckle noise due to the star light scattered by instrumental…

Imaging the planets that orbit around other stars requires blocking the host star which is usually 8-10 orders of magnitude brighter than the planets. This is achieved with the help of a stellar coronagraph. In the current work, a concept…

Instrumentation and Methods for Astrophysics · Physics 2022-11-29 Bhavesh Jaiswal

Future instruments need efficient coronagraphs over large spectral ranges to enable broadband imaging or spectral characterization of exoplanets 1e8 fainter than their star. Several solutions were proposed. Pupil apodizers can attenuate the…

Instrumentation and Methods for Astrophysics · Physics 2020-03-11 Raphaël Galicher , Pierre Baudoz , Elsa Huby , Olivier Dupuis

The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) will be the first high-performance stellar coronagraph using active wavefront control for deep starlight suppression in space, providing unprecedented levels of…

Uncorrected wavefront errors create speckle noise in high-contrast observations at small inner-working angles. These speckles can be sensed and controlled by using coronagraph integrated wavefront sensors. Here, we will present how the…

Instrumentation and Methods for Astrophysics · Physics 2023-10-18 Sebastiaan Y. Haffert , Jared R. Males , Olivier Guyon

The specification of polishing requirements for the optics in coronagraphs dedicated to exo-planet detection requires careful and accurate optical modelling. Numerical representations of the propagation of aberrations through the system as…

Instrumentation and Methods for Astrophysics · Physics 2011-11-07 Laurent Pueyo , N. Jeremy Kasdin , Stuart Shaklan

We present the SPICA Coronagraphic Instrument (SCI), which has been designed for a concentrated study of extra-solar planets (exoplanets). SPICA mission provides us with a unique opportunity to make high contrast observations because of its…

The PIAA is a now well demonstrated high contrast technique that uses an intermediate remapping of the pupil for high contrast coronagraphy (apodization), before restoring it to recover classical imaging capabilities. This paper presents…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Frantz Martinache , Olivier Guyon , Christophe Clergeon , Celia Blain

We describe a new instrument that forms the core of a long-term high contrast imaging program at the 200-inch Hale Telescope at Palomar Observatory. The primary scientific thrust is to obtain images and low-resolution spectroscopy of brown…

We report on the Achromatic Interfero Coronagraph, a focal imaging device which aims at rejecting the energy contribution of a point-like source set on-axis, so as to make detectable its angularly-close environment (applicable to stellar…

Astrophysics · Physics 2009-07-09 Yves Rabbia , Jean Gay , Jean-Pierre Rivet

We present recent laboratory results demonstrating high-contrast coronagraphy for the future space-based large IR/Optical/Ultraviolet telescope recommended by the Decadal Survey. The High-contrast Imager for Complex Aperture Telescopes…

High-contrast imaging will be a challenge for future ELTs, because their vibrations create low-order aberrations - mostly tip/tilt - that reduce coronagraphic performances at 1.2 lambda/D and above. A Low-Order WaveFront Sensor (LOWFS) is…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Julien Lozi , Ruslan Belikov , Glenn Schneider , Olivier Guyon , EugenePluzhnik , Sandrine J. Thomas , Frantz Martinache

High contrast imaging using coronagraphy is one of the main avenues to enable the search for life on extrasolar Earth analogs. The HiCAT testbed aims to demonstrate coronagraphy and wavefront control for segmented on-axis space telescopes…

Instrumentation and Methods for Astrophysics · Physics 2019-03-11 Christopher Moriarty , Keira Brooks , Remi Soummer , Marshall Perrin , Thomas Comeau , Gregory Brady , Rob Gontrum , Peter Petrone

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…

Astrophysics · Physics 2009-11-10 James P. Lloyd , Anand Sivaramakrishnan

Observing Earth-like exoplanets orbiting within the habitable zone of Sun-like stars and studying their atmospheres in reflected starlight requires contrasts of $\sim1\mathrm{e}{-10}$ in the visible. At such high contrast, starlight…

Earth and Planetary Astrophysics · Physics 2022-11-09 Jens Kammerer , Christopher C. Stark , Kevin J. Ludwick , Roser Juanola-Parramon , Bijan Nemati

Future large segmented space telescopes and their coronagraphic instruments are expected to provide the resolution and sensitivity to observe Earth-like planets with a 10^10 contrast ratio at less than 100 mas from their host star. Advanced…

We have reported previously on a new method we are developing for using image-based information to improve global coronal magnetic field models. In that work we presented early tests of the method which proved its capability to improve…

Solar and Stellar Astrophysics · Physics 2017-08-02 Shaela I. Jones , Joseph M. Davila , Vadim M. Uritsky

We describe a coronagraphic optic for use with CONICA at the VLT that provides suppression of diffraction from 1.8 to 7 lambda/D at 4.05 microns, an optimal wavelength for direct imaging of cool extrasolar planets. The optic is designed to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Matthew A. Kenworthy , Sascha P. Quanz , Michael R. Meyer , Markus E. Kasper , Rainer Lenzen , Johanan L. Codona , Julien H. V. Girard , Philip M. Hinz

Detection and characterization of exoplanets by direct imaging requires a coronagraph designed to deliver high contrast at small angular separation. To achieve this, an accurate control of low order aberrations, such as pointing and focus…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Frédéric P. A. Vogt , Frantz Martinache , Olivier Guyon , Takashi Yoshikawa , Kaito Yokochi , Vincent Garrel , Taro Matsuo

The coronagraph instrument on the WFIRST-AFTA mission study has two coronagraphic architectures, shaped pupil and hybrid Lyot, which may be interchanged for use in different observing scenarios. Each architecture relies on newly-developed…

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