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Related papers: Fast simulations of extragalactic microlensing

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High resolution light-sheet optical microscopy requires illuminating a sample by a thin excitation light sheet with large area. Here, we describe methods for producing light sheets with extended length, as compared to Gaussian-beam-type…

Optics · Physics 2019-09-04 Shengwang Du , Teng Zhao , Luwei Zhao

Gravitational microlensing events of high magnification have been shown to be promising targets for detecting extrasolar planets. However, only a few events of high magnification have been found using conventional survey techniques. Here we…

The gravitational fields of astrophysical bodies bend the light around them, creating multiple paths along which light from a distant source can arrive at Earth. Measuring the difference in photon arrival time along these different paths…

Imaging in thick biological tissues is often degraded by sample-induced aberrations, which reduce image quality and resolution, particularly in super-resolution techniques. While hardware-based adaptive optics, which correct aberrations…

We introduce a loss compensation method to increase the resolution of near-field imaging with a plasmonic superlens that relies on the convolution of a high spatial frequency passband function with the object. Implementation with incoherent…

Optics · Physics 2018-01-23 Wyatt Adams , Anindya Ghoshroy , Durdu Ö. Güney

Light sheet fluorescence microscopy is able to image large specimen with high resolution by imaging the sam- ples from multiple angles. Multi-view deconvolution can significantly improve the resolution and contrast of the images, but its…

Quantitative Methods · Quantitative Biology 2014-12-03 Stephan Preibisch , Fernando Amat , Evangelia Stamataki , Mihail Sarov , Robert H. Singer , Eugene Myers , Pavel Tomancak

With increasingly large data sets, weak lensing measurements are able to measure cosmological parameters with ever greater precision. However this increased accuracy also places greater demands on the statistical tools used to extract the…

Astrophysics · Physics 2015-05-13 S. Pires , J. -L. Starck , A. Amara , R. Teyssier , A. Refregier , J. Fadili

The potential of the gravitational microlensing inside our Galaxy for testing the Einstein formula for the gravitational light deflection is discussed. For this purpose, the lens mapping is modified by introducing parameter eps, which…

General Relativity and Quantum Cosmology · Physics 2020-12-22 A. N. Alexandrov , V. M. Sliusar , V. I. Zhdanov

Weak gravitational lensing is a powerful probe of the large-scale cosmic matter distribution. Wide-field galaxy surveys allow us to generate the so-called weak lensing maps, but actual observations suffer from noise due to imperfect…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-21 Masato Shirasaki , Naoki Yoshida , Shiro Ikeda

In the era of large-scale astronomical surveys, fast modeling of strong lens systems has become increasingly vital. While significant progress has been made for galaxy-scale lenses, the development of automated methods for modeling larger…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-05 F. Urcelay , E. Jullo , L. F. Barrientos , X. Huang , J. Hernandez

We develop a new tool to generate statistically precise dark matter maps from the cosmic magnification of galaxies with distance estimates. We show how to overcome the intrinsic clustering problem using the slope of the luminosity function,…

Astrophysics · Physics 2008-11-26 Pengjie Zhang , Ue-Li Pen

We investigate the merits of a massive forward modeling of ground-based optical imaging as a diagnostic for the strong lensing nature of Early-Type Galaxies, in the light of which blurred and faint Einstein rings can hide. We simulate…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Florence Brault , Raphael Gavazzi

The Pixon method is a high-performance, nonlinear image reconstruction method that provides statistically unbiased photometry and robust rejection of spurious sources. Relative to other methods, it can increase linear spatial resolution by…

Astrophysics · Physics 2009-09-25 Richard C. Puetter , Amos Yahil

I present a new algorithm, CALCLENS, for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This new algorithm properly accounts for the sky curvature and boundary…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-15 Matthew R. Becker

We study the limits of accuracy for weak lensing maps of dark matter using diffuse 21-cm radiation from the pre-reionization epoch using simulations. We improve on previous "optimal" quadratic lensing estimators by using shear and…

Astrophysics · Physics 2009-11-13 Tingting Lu , Ue-Li Pen

We outline the super-resolution reconstruction problem posed as a maximization of probability. We then introduce an interpolation method based on polygonal pixel overlap, express it as a linear operator, and use it to improve…

Computer Vision and Pattern Recognition · Computer Science 2012-10-17 Stéfan J. van der Walt , B. M. Herbst

I describe a new, open-source astronomical image-fitting program called Imfit, specialized for galaxies but potentially useful for other sources, which is fast, flexible, and highly extensible. A key characteristic of the program is an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Peter Erwin

Quasar microlensing is both a very useful tool in cosmology and astrophysics, and a source of uncertainty in some studies like the determination of the Hubble constant from lensed quasars. Microlensing probability and time-scales have been…

Astrophysics of Galaxies · Physics 2026-05-06 F. Ávila-Vera , V. Motta , E. Mediavilla

This paper presents a deep learning method for faster magnetic resonance imaging (MRI) by reducing k-space data with sub-Nyquist sampling strategies and provides a rationale for why the proposed approach works well. Uniform subsampling is…

Machine Learning · Statistics 2019-05-14 Chang Min Hyun , Hwa Pyung Kim , Sung Min Lee , Sungchul Lee , Jin Keun Seo

The matrix formation associated to high-order discretizations is known to be numerically demanding. Based on the existing procedure of interpolation and lookup, we design a multiscale assembly procedure to reduce the exorbitant assembly…

Numerical Analysis · Mathematics 2021-07-21 Thibaut Hirschler , Pablo Antolin , Annalisa Buffa