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Related papers: Low-order wavefront control using a Zernike sensor…

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Exoplanet imaging has thus far enabled studies of wide-orbit ($>$10 AU) giant planet ($>$2 Jupiter masses) formation and giant planet atmospheres, with future 30 meter-class Extremely Large Telescopes (ELTs) needed to image and characterize…

Instrumentation and Methods for Astrophysics · Physics 2023-08-14 Benjamin L. Gerard , Daren Dillon , Sylvain Cetre , Rebecca Jensen-Clem

Wavefront sensing with a thin diffuser has emerged as a potential low-cost alternative to a lenslet array for aberrometry. Diffuser wavefront sensors (DWS) have previously relied on tracking speckle displacement and consequently require…

Optics · Physics 2019-01-01 Gregory N. McKay , Faisal Mahmood , Nicholas J. Durr

High-contrast imaging instruments need extreme wavefront control to directly image exoplanets. This requires highly sensitive wavefront sensors which optimally make use of the available photons to sense the wavefront. Here, we propose to…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Rico Landman , Christoph Keller , Emiel H. Por , Sebastiaan Haffert , David Doelman , Thijs Stockmans

The continual push to directly image exoplanets at lower masses and closer separations orbiting around bright stars remains limited by both quasi-static and residual adaptive optics (AO) aberration. In previous papers we have proposed a…

Instrumentation and Methods for Astrophysics · Physics 2020-04-29 Benjamin Gerard , Christian Marois

High-contrast imaging has been used to discover and characterize dozens of exoplanets to date. The primary limiting performance factor for these instruments is contrast, the ratio of exoplanet to host star brightness that an instrument can…

Direct detection and spectroscopy of exoplanets requires high contrast imaging. For habitable exoplanets in particular, located at small angular separation from the host star, it is crucial to employ small inner working angle (IWA)…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 P. Pathak , O. Guyon , N. Jovanovic , J. Lozi , F. Martinache , Y. Minowa , T. Kudo , H. Takami , Y. Hayano , N. Narita

This paper provides a framework for the incorporation of the wavefront sensor measurements in the context of observing modes in which the science camera takes millisecond exposures. In this formulation, the wavefront sensor measurements…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Richard A. Frazin

The baseline contrast floor from the Roman Coronagraph's High-Order Wavefront Sensing and Control strategy likely degrades over the course of time, requiring periodic recalibration of the dark hole. Here, we propose to consider spatial…

Instrumentation and Methods for Astrophysics · Physics 2025-09-12 Thayne Currie , Olivier Guyon , Ruslan Belikov , Dan Sirbu , Mona El Morsy

The challenges of high contrast imaging (HCI) for detecting exoplanets for both ground and space applications can be met with extreme adaptive optics (ExAO), a high-order adaptive optics system that performs wavefront sensing (WFS) and…

Very high dynamical range coronagraphs targeting direct exo-planet detection (10^9 - 10^10 contrast) at small angular separation (few lambda/D units) usually require an input wavefront quality on the order of ten thousandths of wavelength…

Astrophysics · Physics 2009-11-13 J. Nishikawa , L. Abe , N. Murakami , T. Kotani

Future large space telescopes will be equipped with adaptive optics (AO) to overcome wavefront aberrations and achieve high contrast for imaging faint astronomical objects, such as earth-like exoplanets and debris disks. In contrast to AO…

Instrumentation and Methods for Astrophysics · Physics 2020-01-07 He Sun , N. Jeremy Kasdin , Robert Vanderbei

The 2020 Decadal Survey on Astronomy and Astrophysics endorsed space-based high contrast imaging for the detection and characterization of habitable exoplanets as a key priority for the upcoming decade. To advance the maturity of starlight…

Extra-solar planets direct imaging is now a reality with the deployment and commissioning of the first generation of specialized ground-based instruments (GPI, SPHERE, P1640 and SCExAO). These systems allow of planets $ 10 ^ 7 $ times…

Instrumentation and Methods for Astrophysics · Physics 2015-09-16 Sandrine J. Thomas , Ruslan Belikov , Eduardo Bendek

Coronagraphic imaging of exoplanets using ground-based instruments on large telescopes is intrinsically limited by speckles induced by uncorrected aberrations. These aberrations originate from the imperfect correction of the atmosphere by…

Instrumentation and Methods for Astrophysics · Physics 2022-05-04 A. Vigan , K. Dohlen , M. N'Diaye , F. Cantalloube , J. Girard , J. Milli , J. -F. Sauvage , Z. Wahhaj , G. Zins , J. -L. Beuzit , A. Caillat , A. Costille , J. Le Merrer , D. Mouillet , S. Tourenq

Differentiating between an exoplanet signal and residual speckle noise is a key challenge in high-contrast imaging. Speckles are due to a combination of fast, slow and static wavefront aberrations introduced by atmospheric turbulence and…

Laser guide star (LGS) wave-front sensing (LGSWFS) is a key element of tomographic adaptive optics system. However, when considering Extremely Large Telescope (ELT) scales, the LGS spot elongation becomes so large that it challenges the…

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

We propose a coronagraphic system with fourth-order null for off-axis segmented telescopes, which is sufficiently insensitive to the telescope pointing errors and finite angular diameter of the host star to enable high-contrast imaging of…

Instrumentation and Methods for Astrophysics · Physics 2020-05-06 Satoshi Itoh , Taro Matsuo

High performance coronagraphic imaging at small inner working angle requires efficient control of low order aberrations. The absence of accurate pointing control at small separation not only degrades coronagraph starlight rejection but also…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Garima Singh , Frantz Martinache , Pierre Baudoz , Olivier Guyon , Taro Matsuo , Christophe Clergeon

In the context of exoplanet detection, the performance of coronagraphs is limited by wavefront errors. To efficiently correct for these aberrations with a deformable mirror, it is mandatory to measure them using the science detector with a…

Astrophysics · Physics 2009-11-13 R. Galicher , P. Baudoz , G. Rousset