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Shack-Hartmann wavefront sensors (SHWS) are generally used to measure the wavefront curvature of light beams. Measurement accuracy and the sensitivity of these sensors are important factors for better wavefront sensing. In this study, we…

Optics · Physics 2021-10-04 Nitin Dubey , Ravi Kumar , Joseph Rosen

Hyperspectral cameras face harsh trade-offs between spatial, spectral, and temporal resolution in inherently low-photon conditions. Computational imaging systems break through these trade-offs with compressive sensing, but have required…

Computer Vision and Pattern Recognition · Computer Science 2026-02-12 M. Kerem Aydin , Yi-Chun Hung , Jaclyn Pytlarz , Qi Guo , Emma Alexander

While passive acoustic mapping (PAM) has been advanced for monitoring acoustic cavitation activity in focused ultrasound (FUS) therapy, achieving both real-time and high-quality imaging capabilities is still challenging. The angular…

Medical Physics · Physics 2024-12-04 Yi Zeng , Hui Zhu , Jinwei Li , Jianfeng Li , Fei Li , Shukuan Lu , Xiran Cai

The Astro2020 decadal survey recommended an infrared, optical, ultra-violet (IR/O/UV) telescope with a $\sim$6~m inscribed diameter and equipped with a coronagraph instrument to directly image exoEarths in the habitable zone of their host…

Context. High-contrast exoplanet imaging is a rapidly growing field as can be seen through the significant resources invested. In fact, the detection and characterization of exoplanets through direct imaging is featured at all major…

Instrumentation and Methods for Astrophysics · Physics 2018-04-17 Markus J. Bonse , Sascha P. Quanz , Adam Amara

Most current high contrast imaging point spread function (PSF) subtraction algorithms use some form of a least-squares noise minimization to find exoplanets that are, before post-processing, often hidden below the instrumental speckle…

Instrumentation and Methods for Astrophysics · Physics 2016-09-29 Benjamin L. Gerard , Christian Marois

In this article we show that the vector-Apodizing Phase Plate (vAPP) coronagraph can be designed such that the coronagraphic point spread functions (PSFs) can act as a wavefront sensor to measure and correct the (quasi-)static aberrations,…

Instrumentation and Methods for Astrophysics · Physics 2019-11-27 Steven P. Bos , David S. Doelman , Julien Lozi , Olivier Guyon , Christoph U. Keller , Kelsey L. Miller , Nemanja Jovanovic , Frantz Martinache , Frans Snik

Current and future imaging surveys will measure cosmic shear with a statistical precision that demands a deeper understanding of potential systematic biases in galaxy shape measurements than has been achieved to date. We investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 J. E. Meyers , P. R. Burchat

The EXoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) science mission concept uses a visible-wavelength Phase-Induced Amplitude Apodization (PIAA) coronagraph to enable high-contrast imaging of circumstellar debris systems…

Instrumentation and Methods for Astrophysics · Physics 2017-09-11 Dan Sirbu , Sandrine J. Thomas , Ruslan Belikov , Julien Lozi , Eduardo Bendek , Eugene Pluzhnik , Dana H. Lynch , Troy Hix , Peter Zell , Olivier Guyon , Glenn Schneider

Exo-NINJA will realize nearIR R$\sim$4000 diffraction-limited narrow-field spectro-imaging for characterization of exoplanets and circumstellar disk structures. It uniquely combines mid-R spectroscopy, high throughput, and spatial…

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

We use observations with the infrared-optimized MagAO system and Clio camera in 3.9 $\mu$m light to place stringent mass constraints on possible undetected companions to Sirius A. We suppress the light from Sirius A by imaging it through a…

An accurate model of the point spread function is required in order to estimate positions and brightnesses of stars in digitized images. The PSF of the Gaia space telescope is unusual due to the use of drift-scan mode and time-delayed…

Instrumentation and Methods for Astrophysics · Physics 2026-04-08 Nicholas Rowell , Michael Davidson , Nigel C. Hambly , Lennart Lindegren , Javier Castañeda , Claus Fabricius , Jose Hernández , Dafydd W. Evans

When recording spectra from the ground, atmospheric turbulence causes degradation of the spatial resolution. We present a data reduction method that restores the spatial resolution of the spectra to their undegraded state. By assuming that…

Instrumentation and Methods for Astrophysics · Physics 2017-12-13 Michiel van Noort

Due to their high frame rates, high sensitivity, low noise, and low dark current, SAPHIRA detectors provide new capabilities for astronomical observations. The SAPHIRA detector is a 320x256@24 $\mu$m pixel HgCdTe linear avalanche photodiode…

Instrumentation and Methods for Astrophysics · Physics 2018-07-16 Sean Goebel

We analysed state-of-the-art observations of the solar atmosphere to investigate the dependence of the \ca brightness of several solar features on spectral bandwidth and spatial resolution of the data. Specifically, we study data obtained…

Solar and Stellar Astrophysics · Physics 2023-04-20 M. Murabito , I. Ermolli , T. Chatzistergos , S. Jafarzadeh , F. Giorgi , L. Rouppe van der Voort

We present a reanalysis of the VIRMOS-Descart weak lensing data, with a particular focus on different corrections for the variation of the point spread function anisotropy (PSF) across the CCDs. We show that the small scale systematics can…

Astrophysics · Physics 2009-11-10 L. Van Waerbeke , Y. Mellier , H. Hoekstra

Context. Circumstellar disks and self-luminous giant exoplanets or companion brown dwarfs can be characterized through direct-imaging polarimetry at near-infrared wavelengths. SPHERE/IRDIS at the Very Large Telescope has the capabilities to…

Spectro-microscopy is an experimental technique which can be used to observe spatial variations in chemical state and changes in chemical state over time or under experimental conditions. As a result it has broad applications across areas…

Medical Physics · Physics 2026-02-05 Maike Meier , Lorenzo Lazzarino , Boris Shustin , Hussam Al Daas , Paul Quinn

The scientific yield of current and future optical surveys is increasingly limited by systematic uncertainties in the flux calibration. This is the case for Type Ia supernova (SN Ia) cosmology programs, where an improved calibration…

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