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Establishing a precise connection between imaged intensity and the incident wavefront is essential for emerging applications in adaptive optics, holography, computational microscopy, and non-line-of-sight imaging. While prior work has shown…

Image and Video Processing · Electrical Eng. & Systems 2026-04-02 Ali Almuallem , Nicholas Chimitt , Bole Ma , Qi Guo , Stanley H. Chan

We demostrate that the measurement of fluctuations of polarization due to the galactic interstellar scintillations may be used to study the structure of the radiation field at compact radio sources. We develop a mathematical formalism and…

Astrophysics · Physics 2009-10-31 Mikhail V. Medvedev

Organic glass scintillators are an interesting alternative to liquid scintillators, offering many advantageous characteristics with few drawbacks. In this paper we investigate the influence of light self-absorption in the organic glass…

Current projects for large telescopes demand a proper knowledge of atmospheric turbulence to design efficient adaptive optics systems in order to reach large Strehl ratios. However, the proper characterization of the turbulence above a…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 B. Garcia-Lorenzo , A. Eff-Darwich , J. J. Fuensalida , J. Castro-Almazan

We show that surface waves along interstellar current sheets closely aligned with the line of sight lead to pulsar scintillation properties consistent with those observed. This mechanism naturally produces the length and density scales of…

Astrophysics of Galaxies · Physics 2015-06-15 Ue-Li Pen , Yuri Levin

The problem of imaging extended targets (sources or scatterers) is formulated in the framework of compressed sensing with emphasis on subwavelength resolution. The proposed formulation of the problems of inverse source/scattering is…

Optics · Physics 2009-09-15 Albert C. Fannjiang

In astronomy or biological imaging, refractive index inhomogeneities of e.g. atmosphere or tissues induce optical aberrations which degrade the desired information hidden behind the medium. A standard approach consists in measuring these…

Optics · Physics 2023-06-01 Tengfei Wu , Marc Guillon , Gilles Tessier , Pascal Berto

This paper presents a central limit theorem for a pre-averaged version of the realized covariance estimator for the quadratic covariation of a discretely observed semimartingale with noise. The semimartingale possibly has jumps, while the…

Statistics Theory · Mathematics 2016-03-31 Yuta Koike

A pulsar's scintillation bandwidth is inversely proportional to the scattering delay, making accurate measurements of scintillation bandwidth critical to characterize unmitigated delays in efforts to measure low-frequency gravitational…

Several site-testing programs and observatories currently use combined MASS-DIMM instruments for monitoring parameters of optical turbulence. The instrument is described here. After a short recall of the measured quantities and operational…

Astrophysics · Physics 2009-11-13 V. Kornilov , A. Tokovinin , N. Shatsky , O. Voziakova , S. Potanin , B. Safonov

Continuous wavefront sensing on future space telescopes allows relaxation of stability requirements while still allowing on-orbit diffraction-limited optical performance. We consider the suitability of phase retrieval to continuously…

Instrumentation and Methods for Astrophysics · Physics 2023-09-14 Hyukmo Kang , Kyle Van Gorkom , Jess Johnson , Ole Singlestad , Aaron Goldtooth , Daewook Kim , Ewan S. Douglas

We present the details of predicting atmospheric turbulence by mining Zernike moment data obtained from simulations as well as experiments. Temporally correlated optical wave-fronts were simulated such that they followed Kolmogorov phase…

Instrumentation and Methods for Astrophysics · Physics 2011-09-14 Akondi Vyas , M. B. Roopashree , B. Raghavendra Prasad

(Abbreviated) We show that the XRT spectral response calibration was complicated by various energy offsets in photon counting (PC) and windowed timing (WT) modes related to the way the CCD is operated in orbit (variation in temperature…

Objective: This study aimed at investigating through Monte Carlo simulations the limitations of a novel hybrid Cerenkov-scintillation detector and the associated method for irradiation angle measurements. Approach: Using Monte Carlo…

Medical Physics · Physics 2022-12-28 Emilie Jean , Simon Lambert-Girard , Francois Therriault-Proulx , Luc Beaulieu

Impacts of observational systematic errors on the lensing analysis of the cosmic microwave background (CMB) polarization are investigated by numerical simulations. We model errors of gain, angle, and pointing in observation of the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-10 Ryo Nagata , Toshiya Namikawa

Precise measurement of neutrino-nucleus interactions with an accelerator neutrino beam is highly important for current and future neutrino oscillation experiments. To measure muon-neutrino charged-current interactions with…

Far-field slit-diffraction of circular optical-vortex (OV) beams is efficient for measurement of the topological charge (TC) magnitude but does not reveal its sign. We show that this is because in the common diffraction schemes the…

Optics · Physics 2020-10-13 A. Bekshaev , L. Mikhaylovskaya , S. Patil , V. Kumar , R. P. Singh

Event-based sensors detect only changes in brightness across a scene, with each pixel producing an asynchronous stream of spatial-temporal data, rather than recording frames of overall illumination such as a traditional frame-based sensor.…

Instrumentation and Methods for Astrophysics · Physics 2025-04-10 Monique Cockram , Noelia Martinez Rey

Knowledge of the Earth's atmospheric optical turbulence is critical for astronomical instrumentation. Not only does it enable performance verification and optimisation of existing systems but it is required for the design of future…

Instrumentation and Methods for Astrophysics · Physics 2018-06-13 J. Osborn , R. W. Wilson , M. Sarazin , T. Butterley , A. Chacón , F. Derie , O. J. D. Farley , X. Haubois , D. Laidlaw , M. LeLouarn , E. Masciadri , J. Milli , J. Navarrete , M. J. Townson

Using the Cryogenic, High-Accuracy Refraction Measuring System (CHARMS) at NASA's Goddard Space Flight Center, we have measured the absolute refractive index of five specimens taken from a very large boule of Corning 7980 fused silica from…

Optics · Physics 2008-05-02 Douglas B. Leviton , Bradley J. Frey
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