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Related papers: Angular differential kernel phases

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We present a selection of methods for automatically constructing an optimal kernel model for difference image analysis which require very few external parameters to control the kernel design. Each method consists of two components; namely,…

Instrumentation and Methods for Astrophysics · Physics 2016-01-27 D. M. Bramich , Keith Horne , K. A. Alsubai , E. Bachelet , D. Mislis , N. Parley

In this paper we introduce experimentally the phenomenon of speckle and its interferometric applications. With the popularization of CCD sensors and webcams, it is now easy to acquire speckles patterns, to reduce them and exploit them. The…

Data Analysis, Statistics and Probability · Physics 2009-06-22 Boris Chenaud , Pierre Valvin

Strongly lensed variable quasars can serve as precise cosmological probes, provided that time delays between the image fluxes can be accurately measured. A number of methods have been proposed to address this problem. In this paper, we…

Instrumentation and Methods for Astrophysics · Physics 2016-03-15 Sultanah AL Otaibi , Peter Tiňo , Juan C Cuevas-Tello , Ilya Mandel , Somak Raychaudhury

This paper presents the basic principle and theoretical relationships of an original method allowing to retrieve the Wavefront Errors (WFE) of a ground or space-borne telescope when combining its main pupil with a second, decentered…

Optics · Physics 2011-05-19 Francois Henault

We propose an innovative monolithic interferometer to distinguish the topological charge of radiation carrying orbital angular momentum. Remarkably, our method requires to access only a small portion of the entire wavefront. The proposed…

In computational optics, numerical modeling of diffraction between arbitrary planes offers unparalleled flexibility. However, existing methods suffer from the trade-off between computational accuracy and efficiency. To resolve this dilemma,…

Optics · Physics 2023-12-12 Yiwen Hu , Xin Liu , Shi Feng , Xu Liu , Xiang Hao

In the case of ground-based telescopes equipped with adaptive optics systems, the point spread function (PSF) is only poorly known or completely unknown. Moreover, an accurate modeling of the PSF is in general not available. Therefore in…

Numerical Analysis · Mathematics 2015-06-09 M. Prato , A. La Camera , S. Bonettini , S. Rebegoldi , M. Bertero , P. Boccacci

The limitations of adaptive optics and coronagraph performance make exoplanet detection close to {\lambda}/D extremely difficult with conventional imaging methods. The technique of non-redundant masking (NRM), which turns a filled aperture…

Instrumentation and Methods for Astrophysics · Physics 2019-03-18 Steph Sallum , Andy Skemer

Model inference for dynamical systems aims to estimate the future behaviour of a system from observations. Purely model-free statistical methods, such as Artificial Neural Networks, tend to perform poorly for such tasks. They are therefore…

Machine Learning · Computer Science 2019-08-07 David K. E. Green , Filip Rindler

We report on an optimal binary strategy for angular displacement estimation. The measuring system is a modified Mach-Zehnder interferometer fed by a coherent state carrying orbital angular momentum, and two Dove prisms are embedded in two…

Quantum Physics · Physics 2019-03-27 Jian-Dong Zhang , Zi-Jing Zhang , Long-Zhu Cen , Jun-Yan Hu , Yuan Zhao

W projection is a commonly-used approach to allow interferometric imaging to be accelerated by Fast Fourier Transforms (FFTs), but it can require a huge amount of storage for convolution kernels. The kernels are not separable, but we show…

Instrumentation and Methods for Astrophysics · Physics 2016-01-27 Bruce Merry

The petaling effect, induced by pupil fragmentation from the telescope spider, drastically affects the performance of high contrast instruments by inducing core splitting on the PSF. Differential piston/tip/tilt aberrations within each…

An unbiased method for improving the resolution of astronomical images is presented. The strategy at the core of this method is to establish a linear transformation between the recorded image and an improved image at some desirable…

Astrophysics · Physics 2016-08-30 F. P. Pijpers

High precision differential astrometry assesses the positions, distances, and motions of celestial objects in relation to the stars. The focal plane of such space telescope must be calibrated with a precision down to the level of 1e-5 pixel…

Instrumentation and Methods for Astrophysics · Physics 2024-10-30 Fabrice Pancher , Sebastien Soler , Fabien Malbet , Manon Lizzana , Pierre Kern , Thierry Lepine , Alain Leger

In principle, diffractive optics, particularly Phase Fresnel Lenses (PFLs), offer the ability to construct large, diffraction-limited, and highly efficient X-ray/$\gamma$-ray telescopes, leading to dramatic improvement in angular resolution…

High-contrast imaging observations of large angular diameter stars enable complementary science questions to be addressed compared to the baseline goals of proposed missions like the Terrestrial Planet Finder-Coronagraph, New World's…

Earth and Planetary Astrophysics · Physics 2015-05-14 Justin R. Crepp , Suvrath Mahadevan , Jian Ge

Directly imaging Earth-like exoplanets (``exoEarths'') with a coronagraph instrument on a space telescope requires a stable wavefront with optical path differences limited to tens of picometers RMS during exposure times of a few hours.…

In order to measure the radial displacements of facets on surface of a growing spherical Cu_{2-\delta}Se crystal with sub-nanometer resolution, we have investigated the reliability and accuracy of standard method of Fourier analysis of…

Optics · Physics 2009-11-13 Jadranko Gladic , Zlatko Vucic , Davorin Lovric

In the context of difference image analysis (DIA), we present a new method for determining the convolution kernel matching a pair of images of the same field. Unlike the standard DIA technique which involves modelling the kernel as a linear…

Astrophysics · Physics 2009-11-13 D. M. Bramich

We present a new processing technique aimed at significantly improving the angular differential imaging method (ADI) in the context of high-contrast imaging of faint objects nearby bright stars in observations obtained with extreme adaptive…

Instrumentation and Methods for Astrophysics · Physics 2017-11-15 Gianluca Li Causi , Marco Stangalini , Simone Antoniucci , Fernando Pedichini , Massimiliano Mattioli , Vincenzo Testa
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