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Related papers: An apodizing phase plate coronagraph for VLT/NACO

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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…

Instrumentation and Methods for Astrophysics · Physics 2022-09-21 Axel Potier , Johan Mazoyer , Zahed Wahhaj , Pierre Baudoz , Gael Chauvin , Raphael Galicher , Garreth Ruane

The Phase-Induced Amplitude Apodization (PIAA) coronagraph is a high performance coronagraph concept able to work at small angular separation with little loss in throughput. We present results obtained with a laboratory PIAA system…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Olivier Guyon , Eugene Pluzhnik , Frantz Martinache , Julien Totems , Shinichiro Tanaka , Taro Matsuo , Celia Blain , Ruslan Belikov

A coronagraphic starlight suppression system situated on a future flagship space observatory offers a promising avenue to image Earth-like exoplanets and search for biomarkers in their atmospheric spectra. One NASA mission concept that…

A high contrast imaging technique based on an optical vortex coronagraph (OVC) is used to measure the spatial phase profile induced by an air plasma generated by a femtosecond laser pulse. The sensitivity of the OVC method significantly…

For future space infrared astronomical coronagraphy, we perform experimental studies on the application of aluminum mirrors to a coronagraph. Cooled reflective optics is required for broad-band mid-infrared observations in space, while…

Instrumentation and Methods for Astrophysics · Physics 2016-03-09 Shinji Oseki , Shinki Oyabu , Daisuke Ishihara , Keigo Enya , Kanae Haze , Takayuki Kotani , Hidehiro Kaneda , Miho Nishiyama , Lyu Abe , Tomoyasu Yamamuro

The Habitable Worlds Observatory (HWO) mission will require coronagraphs capable of suppressing starlight at the $\sim 10^{-10}$ contrast level to directly image exo-Earths. High contrast achromatic coronagraphic masks are the missing…

Instrumentation and Methods for Astrophysics · Physics 2026-03-25 Niyati Desai , Garreth Ruane , Daniel Shanks , Lorenzo König , Susan Redmond , Bertrand Mennesson

Direct imaging of exoplanets presents a formidable technical challenge owing to the small angular separation and high contrast between exoplanets and their host stars. High Dispersion Coronagraphy (HDC) is a pathway to achieve unprecedented…

Earth and Planetary Astrophysics · Physics 2017-04-05 Ji Wang , Dimitri Mawet , Garreth Ruane , Renyu Hu , Bjorn Benneke

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…

Of the over 5000 exoplanets that have been detected, only about a dozen have ever been directly imaged. Earth-like exoplanets are on the order of 10 billion times fainter than their host star in visible and near-infrared, requiring a…

Instrumentation and Methods for Astrophysics · Physics 2024-02-13 Niyati Desai , Garreth J. Ruane , Jorge D. Llop-Sayson , Arielle Bertrou-Cantou , Axel Potier , A. J. Eldorado Riggs , Eugene Serabyn , Dimitri P. Mawet

For direct imaging of exoplanets, Scalar Vortex Coronagraphs (SVCs) are an attractive alternative to the popularly used Vector Vortex Coronagraphs (VVCs). This is primarily because they are able to induce the same phase ramp regardless of…

Instrumentation and Methods for Astrophysics · Physics 2022-05-24 Niyati Desai , Jorge Llop-Sayson , Nemanja Jovanovic , Garreth Ruane , Eugene Serabyn , Stefan Martin , Dimitri Mawet

In this paper, after briefly reviewing the theory of vectorial vortices, we describe our technological approach to generating the necessary phase helix, and report results obtained with the first optical vectorial vortex coronagraph (OVVC)…

Instrumentation and Methods for Astrophysics · Physics 2010-11-02 D. Mawet , E. Serabyn , K. Liewer , Ch. Hanot , S. McEldowney , D. Shemo , N. O'Brien

High contrast imaging (HCI) is fundamentally limited by wavefront aberrations, and the ability to perform wavefront sensing from focal plane images is key to reach the full potential of ground and space-based instruments. Vortex focal plane…

Instrumentation and Methods for Astrophysics · Physics 2024-07-22 Gilles Orban de Xivry , Olivier Absil

Spectral characterization of young, giant exoplanets detected by direct imaging is one of the tasks of the new generation of high-contrast imagers. For this purpose, the VLT/SPHERE instrument includes a unique long-slit spectroscopy (LSS)…

We present a MIR coronagraph to target the direct observation of extrasolar planets for SPICA, in which a coronagraph is currently regarded as an option of the focal plane instruments. The primary target of the SPICA coronagraph is the…

Earth and Planetary Astrophysics · Physics 2019-08-14 Keigo Enya

Detecting exoplanets and other faint sources of emitted and reflected light near a bright star requires deeply suppressing the starlight while efficiently transmitting the dim light from its surroundings. This suppression can be carried out…

Instrumentation and Methods for Astrophysics · Physics 2024-11-07 Eugene Serabyn , Michael Bottom

We present the results of the first laboratory experiment of checkerboard shaped pupil binary mask coronagraphs using visible light, in the context of the R&D activities for future mid-infrared space missions such as the 3.5 m SPICA…

Astrophysics · Physics 2009-11-11 K. Enya , S. Tanaka , L. Abe , T. Nakagawa

Directly imaging and characterizing Earth-like exoplanets is a tremendously difficult instrumental challenge. Present coronagraphic systems have yet to achieve the required $10^{-10}$ broadband contrast in a laboratory environment, but…

Instrumentation and Methods for Astrophysics · Physics 2019-07-10 Carl T. Coker , Stuart B. Shaklan , A J E. Riggs , Garreth Ruane

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…

Earth and Planetary Astrophysics · Physics 2014-06-05 Hajime Kawahara , Naoshi Murakami , Taro Matsuo , Takayuki Kotani

High-dispersion coronagraphy (HDC) optimally combines high contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway towards fully…

Imaging exoplanetary systems is essential to characterizing exoplanetary systems and to studying planet-disk interactions to understand planet formation. Such imaging in the visible and near-infrared is challenging because these objects are…

Instrumentation and Methods for Astrophysics · Physics 2024-03-29 Raphael Galicher , Axel Potier , Johan Mazoyer , Zahed Wahhaj , Pierre Baudoz , Gaël Chauvin
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