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Due to turbulence in the atmosphere images taken from ground-based telescopes become distorted. With adaptive optics (AO) images can be given greater clarity allowing for better observations with existing telescopes and are essential for…

Instrumentation and Methods for Astrophysics · Physics 2023-08-30 Javier Perez Soto , Cesar Laguna , Benjamin L. Gerard , Anne Dattilo , Vincent Chambouleyron , Rebecca Jensen-Clem

The Coronagraph Instrument (CGI) for NASA's Wide Field Infrared Survey Telescope (WFIRST) will constitute a dramatic step forward for high-contrast imaging, integral field spectroscopy, and polarimetry of exoplanets and circumstellar disks,…

Cardiac motion estimation is an important diagnostic tool to detect heart diseases and it has been explored with modalities such as MRI and conventional ultrasound (US) sequences. US cardiac motion estimation still presents challenges…

Computer Vision and Pattern Recognition · Computer Science 2017-04-26 Angelica I. Aviles , Thomas Widlak , Alicia Casals , Maartje M. Nillesen , Habib Ammari

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

Imaging terrestrial exoplanets around nearby stars is a formidable technical challenge, requiring the development of coronagraphs to suppress the stellar halo of diffracted light at the location of the planet. In this review, we derive the…

Instrumentation and Methods for Astrophysics · Physics 2025-06-04 Matthew A. Kenworthy , Sebastiaan Y. Haffert

Vortex coronagraphs are an attractive solution for imaging exoplanets with future space telescopes due to their relatively high throughput, large spectral bandwidth, and low sensitivity to low-order aberrations compared to other…

Instrumentation and Methods for Astrophysics · Physics 2019-09-11 Garreth Ruane , Dimitri Mawet , A J Eldorado Riggs , Eugene Serabyn

Coronary angiography is considered to be a safe tool for the evaluation of coronary artery disease and perform in approximately 12 million patients each year worldwide. [1] In most cases, angiograms are manually analyzed by a cardiologist.…

Computer Vision and Pattern Recognition · Computer Science 2017-06-07 Stanislav Filippov , Arsenii Moiseev , Andronenko Andrey

Thanks to its capability of acquiring full-view frames at multiple kilohertz, ultrafast ultrasound imaging unlocked the analysis of rapidly changing physical phenomena in the human body, with pioneering applications such as ultrasensitive…

Image and Video Processing · Electrical Eng. & Systems 2020-12-22 Dimitris Perdios , Manuel Vonlanthen , Florian Martinez , Marcel Arditi , Jean-Philippe Thiran

Motion correction aims to prevent motion artefacts which may be caused by respiration, heartbeat, or head movements for example. In a preliminary step, the measured data is divided in gates corresponding to motion states, and displacement…

Optimization and Control · Mathematics 2024-10-15 Claire Delplancke , Kris Thielemans , Matthias J. Ehrhardt

High-contrast imaging for the detection and characterization of exoplanets relies on the instrument's capability to block out the light of the host star. Some current post-processing methods for calibrating out the residual speckles use…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Marie Ygouf , Laurent M. Mugnier , David Mouillet , Thierry Fusco , Jean-Luc Beuzit

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…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Ronny Errmann , Stefano Minardi , Thomas Pertsch

More than half of the stars in the solar neighborhood reside in binary/multiple stellar systems, and recent studies suggest that gas giant planets may be more abundant around binaries than single stars. Yet, these multiple systems are…

Instrumentation and Methods for Astrophysics · Physics 2018-08-03 Jonas Kuhn , Sebastian Daemgen , Ji Wang , Farisa Morales , Michael Bottom , Eugene Serabyn , Jean C. Shelton , Jacques-Robert Delorme , Samaporn Tinyanont

Direct imaging of exoplanets relies on complex wavefront sensing and control architectures. In addition to fast adaptive optics systems, most of the future high-contrast imaging instruments will soon be equipped with focal plane wavefront…

All coronagraphic instruments for exoplanet high-contrast imaging need wavefront correction systems to reject optical aberrations and create sufficiently dark holes. Since the most efficient wavefront correction algorithms (controllers and…

Instrumentation and Methods for Astrophysics · Physics 2018-10-09 He Sun , N. Jeremy Kasdin , Robert Vanderbei

We introduce two classes of lightweight, adaptive calibration protocols for quantum computers that leverage fast feedback. The first enables shot-by-shot updates to device parameters using measurement outcomes from simple,…

Quantum Physics · Physics 2025-12-09 Alicia B. Magann , Nathan E. Miller , Robin Blume-Kohout , Peter Maunz , Kevin C. Young

Ptychography is a popular imaging technique that combines diffractive imaging with scanning microscopy. The technique consists of a coherent beam that is scanned across an object in a series of overlapping positions, leading to reliable and…

Numerical Analysis · Mathematics 2024-08-08 Ricardo Parada , Samy Wu Fung , Stanley Osher

Non Common Path Aberrations (NCPA) are often considered as a critical issue in Adaptive Optics (AO) systems, since they introduce bias errors between real wavefronts propagating to the science detectors and those measured by the Wavefront…

Instrumentation and Methods for Astrophysics · Physics 2019-09-12 Francois Henault

Quantum code surgery is a promising technique to perform fault-tolerant computation on quantum low-density parity-check codes. Recent developments have significantly reduced the space overhead of surgery. However, generic surgery operations…

Quantum Physics · Physics 2025-10-17 Alexander Cowtan , Zhiyang He , Dominic J. Williamson , Theodore J. Yoder

High-contrast imaging (HCI) observations of exoplanets can be limited by the island effect (IE). On the current generation of telescopes, the IE becomes a severe problem when the ground wind speed is below a few meters per second. This is…

We present an algorithm that uses the distribution of photon arrival times to distinguish speckles from incoherent sources, like planets and disks, in high contrast images. Using simulated data, we show that our approach can overcome the…

Instrumentation and Methods for Astrophysics · Physics 2019-10-09 Alex B. Walter , Clinton Bockstiegel , Timothy D. Brandt , Benjamin A. Mazin
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