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相关论文: KaRMMa -- Kappa Reconstruction for Mass Mapping

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We present MambaCSR, a simple but effective framework based on Mamba for the challenging compressed image super-resolution (CSR) task. Particularly, the scanning strategies of Mamba are crucial for effective contextual knowledge modeling in…

计算机视觉与模式识别 · 计算机科学 2024-11-27 Yulin Ren , Xin Li , Mengxi Guo , Bingchen Li , Shijie Zhao , Zhibo Chen

To take full advantage of the unprecedented power of upcoming weak lensing surveys, understanding the noise, such as cosmic variance and geometry/mask effects, is as important as understanding the signal itself. Accurately quantifying the…

宇宙学与河外天体物理 · 物理学 2016-10-26 Yu Yu , Pengjie Zhang , Yipeng Jing

The ability to obtain reliable point estimates of model parameters is of crucial importance in many fields of physics. This is often a difficult task given that the observed data can have a very high number of dimensions. In order to…

宇宙学与河外天体物理 · 物理学 2021-12-15 Janis Fluri , Aurelien Lucchi , Tomasz Kacprzak , Alexandre Refregier , Thomas Hofmann

Purpose: Undersampling is used to reduce the scan time for high-resolution 3D magnetic resonance imaging. In order to achieve better image quality and avoid manual parameter tuning, we propose a probabilistic Bayesian approach to recover…

图像与视频处理 · 电气工程与系统科学 2022-10-20 Shuai Huang , James J. Lah , Jason W. Allen , Deqiang Qiu

The acquisition of Magnetic Resonance Imaging (MRI) is inherently slow. Inspired by recent advances in deep learning, we propose a framework for reconstructing MR images from undersampled data using a deep cascade of convolutional neural…

计算机视觉与模式识别 · 计算机科学 2017-03-03 Jo Schlemper , Jose Caballero , Joseph V. Hajnal , Anthony Price , Daniel Rueckert

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…

天体物理学 · 物理学 2009-11-13 Tingting Lu , Ue-Li Pen

In many cosmological inference problems, the likelihood (the probability of the observed data as a function of the unknown parameters) is unknown or intractable. This necessitates approximations and assumptions, which can lead to incorrect…

宇宙学与河外天体物理 · 物理学 2020-12-02 Niall Jeffrey , Justin Alsing , François Lanusse

Weak gravitational lensing has proven to be a powerful tool to map directly the distribution of dark matter in the Universe. The technique, currently used, relies on the accurate measurement of the gravitational shear that corresponds to…

宇宙学与河外天体物理 · 物理学 2015-05-19 S. Pires , A. Amara

We have developed a new technique called Direct Shear Mapping (DSM) to measure gravitational lensing shear directly from observations of a single background source. The technique assumes the velocity map of an un-lensed, stably-rotating…

宇宙学与河外天体物理 · 物理学 2015-05-26 Catherine O. de Burgh-Day , Edward N. Taylor , Rachel L. Webster , Andrew M. Hopkins

Dark matter cannot be observed directly, but its weak gravitational lensing slightly distorts the apparent shapes of background galaxies, making weak lensing one of the most promising probes of cosmology. Several observational studies have…

宇宙学与河外天体物理 · 物理学 2018-12-18 Dezső Ribli , Bálint Ármin Pataki , István Csabai

We present a Bayesian reconstruction algorithm that infers the three-dimensional large-scale matter distribution from the weak gravitational lensing effects measured in the image shapes of galaxies. The algorithm is designed to also work…

宇宙学与河外天体物理 · 物理学 2017-12-20 Vanessa Böhm , Stefan Hilbert , Maksim Greiner , Torsten A. Enßlin

Skew-spectra allow us to extract non-Gaussian information by taking the square of a map and finding the power spectrum of this new map with the original map. This allows us to use much of the infrastructure of power spectra and avoid the…

宇宙学与河外天体物理 · 物理学 2026-03-26 Alexander Roskill , Sara Maleubre , David Alonso , Pedro G. Ferreira

Galactic all-sky maps at very disparate frequencies, like in the radio and $\gamma$-ray regime, show similar morphological structures. This mutual information reflects the imprint of the various physical components of the interstellar…

Different options can be used in order to measure the shear from observations in the context of weak lensing. Here we introduce new methods where the isotropy assumption for the distribution of the source galaxies is implemented directly on…

天体物理学 · 物理学 2008-02-03 Marco Lombardi , Giuseppe Bertin

The purpose of image inpainting is to recover scratches and damaged areas using context information from remaining parts. In recent years, thanks to the resurgence of convolutional neural networks (CNNs), image inpainting task has made…

计算机视觉与模式识别 · 计算机科学 2022-05-17 Zeyu Lu , Junjun Jiang , Junqin Huang , Gang Wu , Xianming Liu

We explore the stability of the variance and skewness of the cosmic gravitational convergence field, using two different approaches: first we simulate a whole MEGACAM survey (100 sq. degrees). The reconstructed mass map, obtained from a…

天体物理学 · 物理学 2007-05-23 A. Thion , Y. Mellier , F. Bernardeau , E. Bertin , T. Erben , L. van Waerbeke

The technique of non-redundant masking (NRM) transforms a conventional telescope into an interferometric array. In practice, this provides a much better constrained point spread function than a filled aperture and thus higher resolution…

天体物理仪器与方法 · 物理学 2017-11-29 Steph Sallum , Josh Eisner

Compressive sensing (CS) is a new methodology to capture signals at lower rate than the Nyquist sampling rate when the signals are sparse or sparse in some domain. The performance of CS estimators is analyzed in this paper using tools from…

信息论 · 计算机科学 2014-09-09 Solomon A. Tesfamicael , Bruhtesfa E. Godana , Faraz Barzideh

We revise the Bayesian inference steps required to analyse the cosmological large-scale structure. Here we make special emphasis in the complications which arise due to the non-Gaussian character of the galaxy and matter distribution. In…

宇宙学与河外天体物理 · 物理学 2015-06-03 Francisco-Shu Kitaura

Optimal extraction of cosmological information from observations of the Cosmic Microwave Background critically relies on our ability to accurately undo the distortions caused by weak gravitational lensing. In this work, we demonstrate the…

宇宙学与河外天体物理 · 物理学 2024-06-07 Thomas Flöss , William R. Coulton , Adriaan J. Duivenvoorden , Francisco Villaescusa-Navarro , Benjamin D. Wandelt