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Existing Electric Field Conjugation (EFC) methods are not suited for treating small polarization effects, referred to here as cross polarization. EFC utilizes a deformable mirror (DM) to nullify the electric fields from the host star within…

Instrumentation and Methods for Astrophysics · Physics 2024-10-11 Richard A. Frazin

We present the final results of the Apodized Pupil Lyot Coronagraph (APLC) on the High-contrast imager for Complex Aperture Telescopes (HiCAT) testbed, under NASA's Strategic Astrophysics Technology program. The HiCAT testbed was developed…

Direct imaging of exoplanets represents a challenge for astronomical instrumentation due to the high-contrast ratio and small angular separation between the host star and the faint planet. Multi-star systems pose additional challenges for…

Instrumentation and Methods for Astrophysics · Physics 2017-11-15 Dan Sirbu , Sandrine Thomas , Ruslan Belikov , Eduardo Bendek

The Nancy Grace Roman Space Telescope Coronagraph Instrument is a critical technology demonstrator for NASA's Habitable Worlds Observatory. With a predicted visible-light flux ratio detection limit of 1E-8 or better, it will be capable of…

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

Imaging planets in reflected light, a key focus of future NASA missions and ELTs, requires advanced wavefront control to maintain a deep, temporally correlated null of stellar halo -- i.e. a dark hole -- at just several diffraction beam…

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…

Instrumentation and Methods for Astrophysics · Physics 2015-09-18 John Krist , Bijan Nemati , Bertrand Mennesson

Imaging exo-Earths is an exciting but challenging task because of the 10^-10 contrast ratio between these planets and their host star at separations narrower than 100 mas. Large segmented aperture space telescopes enable the sensitivity…

We propose a new approach for high-contrast imaging at the diffraction limit using segmented telescopes in a modest observation bandwidth. This concept, named "spectroscopic fourth-order coronagraphy", is based on a fourth-order coronagraph…

Instrumentation and Methods for Astrophysics · Physics 2021-03-17 Taro Matsuo , Satoshi Itoh , Yuji Ikeda

A high contrast coronagraph is expected to provide one of the promising ways to directly observe extra-solar planets. We present the newest results of our laboratory experiment investigating "rigid" coronagraph with a binary shaped…

Instrumentation and Methods for Astrophysics · Physics 2011-08-17 K. Enya , L. Abe , S. Tanaka , T. Nakagawa , K. Haze , T. Sato , T. Wakayama

Deformable mirrors (DMs) are a critical technology to enable coronagraphic direct imaging of exoplanets with current and planned ground - and space-based telescopes as well as future mission concepts that aim to image exoplanet types…

Instrumentation and Methods for Astrophysics · Physics 2020-11-05 Eduardo Bendek , Garreth Ruane , Camilo Mejia Prada , Christopher B. Mendillo , A. J. Eldorado Riggs , Eugene Serabyn

We have built a series of notch filter image masks that make the Lyot coronagraph less susceptible to low-spatial-frequency optical aberrations. In this paper, we present experimental results of their performance in the lab using…

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…

The current generation of ground-based coronagraphic instruments uses deformable mirrors to correct for phase errors and to improve contrast levels at small angular separations. Improving these techniques, several space and ground based…

Instrumentation and Methods for Astrophysics · Physics 2017-10-12 Johan Mazoyer , Laurent Pueyo

The Nancy Grace Roman Space Telescope (``Roman'') is a 2.4m space telescope scheduled for a 2026 launch. The Coronagraph Instrument (CGI) on Roman is a technology-demonstration instrument with a coronagraph and, for the first time in space,…

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

We present the first laboratory experiments using a notch-filter mask, a coronagraphic image mask that can produce infinite dynamic range in an ideal Lyot coronagraph according to scalar diffraction theory. We fabricated the first…

Astrophysics · Physics 2009-11-10 J. H. Debes , J. Ge , M. J. Kuchner , M. Rogosky

The correction of quasi-static wavefront errors within a coronagraphic optical system will be a key challenge to overcome in order to directly image exoplanets in reflected light. These quasi-static errors are caused by mid to high-order…

Instrumentation and Methods for Astrophysics · Physics 2024-06-28 Kian Milani , Ewan Douglas , Leonid Pogorelyuk , Christopher Mendillo , Kerri Cahoy , Nicholas Belsten , Brandon Eickert , Shanti Rao

This paper presents the proof-of-concept investigation for a miniaturized vectorcardiogram [VCG] system for ambulatory on-body applications that continuously monitors the electrical activity of the heart in three dimensions. We investigate…

Directly imaging Earth-sized exoplanets with a visible-light coronagraph instrument on a space telescope will require a system that can achieve $\sim10^{-10}$ raw contrast and maintain it for the duration of observations (on the order of…

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