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Related papers: Correlation-based Beam Calibration of 21cm Intensi…

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The high dynamic range between contaminating foreground emission and the fluctuating 21cm brightness temperature field is one of the most problematic characteristics of 21cm intensity mapping data. While these components would ordinarily…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-13 Melis O. Irfan , Philip Bull

We outline a new method for estimating the cosmic infrared background using the spatial and spectral correlation properties of infrared maps. The cosmic infrared background from galaxies should have a minimum fluctuation of the order of…

Astrophysics · Physics 2015-06-24 A. Kashlinsky , J. C. Mather , S. Odenwald , M. G. Hauser

Time-dependent and systematic variations in band gain and central frequencies of instruments used to study the Cosmic Microwave Background are important factors in the data-to-map analysis pipeline. If not properly characterized, they could…

Instrumentation and Methods for Astrophysics · Physics 2018-07-25 J. T. Ward , D. Alonso , J. Errard , M. J. Devlin , M. Hasselfield

We model a 21 cm intensity mapping survey in the redshift range 0.01<z<1.5 designed to simulate the skies as seen by future radio telescopes such as the Square Kilometre Array (SKA), including instrumental noise and Galactic foregrounds. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-27 L. Wolz , F. B. Abdalla , C. Blake , J. R. Shaw , E. Chapman , S. Rawlings

Quantum metrology deals with improving the resolution of instruments that are otherwise limited by shot noise and it is therefore a promising avenue for enabling scientific breakthroughs. The advantage can be even more striking when quantum…

Calibrating out per-antenna signal chain effects is an essential step in analyzing radio interferometric data. For drift-scanning arrays, robustly calibrating the data is especially challenging due to the lack of the ability to track a…

Instrumentation and Methods for Astrophysics · Physics 2026-02-09 Robert Pascua , Jonathan Sievers , Adrian Liu

Current and upcoming 21-cm experiments will soon be able to map 21-cm spatial fluctuations in three dimensions for a wide range of redshifts. However, bright foreground contamination and the nature of radio interferometry create significant…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 Shu-Fan Chen , Kai-Feng Chen , Cora Dvorkin

We report an improved technique for diffuse foreground minimization from Cosmic Microwave Background (CMB) maps using a new multi-phase iterative internal-linear-combination (ILC) approach in harmonic space. The new procedure consists of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-18 Vipin Sudevan , Pavan K. Aluri , Sarvesh Kumar Yadav , Rajib Saha , Tarun Souradeep

Intensity mapping is a promising technique for surveying the large scale structure of our Universe from $z=0$ to $z \sim 150$, using the brightness temperature field of spectral lines to directly observe previously unexplored portions of…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Adrian Liu , Yunfan Zhang , Aaron R. Parsons

A procedure is presented to map from the spatial correlation parameters of a turbulent density field (the radial and binormal correlation lengths and wavenumbers, and the fluctuation amplitude) to correlation parameters that would be…

Plasma Physics · Physics 2017-04-05 M. F. J. Fox , A. R. Field , F. van Wyk , Y. -c. Ghim , A. A. Schekochihin , the MAST Team

Accurate beam modeling is important in many radio astronomy applications. In this paper, we focus on beam modeling for 21-cm intensity mapping experiments using radio interferometers, though the techniques also apply to single dish…

Instrumentation and Methods for Astrophysics · Physics 2025-09-16 Michael J. Wilensky , Philip Bull , Nicolas Fagnoni

Benefiting from its ability to efficiently learn how an object is changing, correlation filters have recently demonstrated excellent performance for rapidly tracking objects. Designing effective features and handling model drifts are two…

Computer Vision and Pattern Recognition · Computer Science 2020-11-26 Xizhe Xue , Ying Li , Qiang Shen

One of the main challenges for future 21 cm observations is to remove foregrounds which are several orders of magnitude more intense than the HI signal. We propose a new technique for removing foregrounds of the redshifted 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jungyeon Cho , A. Lazarian , P. Timbie

Cross-correlation is a popular signal processing technique used in numerous location tracking systems for obtaining reliable range information. However, its efficient design and practical implementation has not yet been achieved on mote…

Other Computer Science · Computer Science 2016-06-14 Prasant Misra , Wen Hu , Mingrui Yang , Marco Duarte , Sanjay Jha

The Virtual Image Correlation method applies for the measurement of silhouettes boundaries with sub-pixel precision. It consists in a correlation between the image of interest and a virtual image based on a parametrized curve. Thanks to a…

Computer Vision and Pattern Recognition · Computer Science 2020-09-11 M. L. M. François

We proposed a novel approach to coherent imaging of dynamic samples. The inter-frame similarity of the sample's local structures is found to be a powerful constraint in phasing a sequence of diffraction patterns. We devised a new image…

Optics · Physics 2024-07-11 Pengju Sheng , Fucai Zhang

Upcoming 21-cm intensity surveys will use the hyperfine transition in emission to map out neutral hydrogen in large volumes of the universe. Unfortunately, large spatial scales are completely contaminated with spectrally smooth…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-27 Chirag Modi , Martin White , Anze Slosar , Emanuele Castorina

Instruments targeting 21~cm emission at high redshifts need a spectral dynamic range of better than ten thousand to distinguish the 21~cm background against bright foregrounds. Systematics arising from the antenna pattern are a leading…

Instrumentation and Methods for Astrophysics · Physics 2026-05-21 Daniel C. Jacobs

We consider imaging of fast moving small objects in space, such as low earth orbit satellites, which are also rotating around a fixed axis. The imaging system consists of ground based, asynchronous sources of radiation and several passive…

Signal Processing · Electrical Eng. & Systems 2021-11-03 Matan Leibovich , George Papanicolaou , Chrysoula Tsogka

Extracting accurate foreground objects from a scene is an essential step for many video applications. Traditional background subtraction algorithms can generate coarse estimates, but generating high quality masks requires professional…

Computer Vision and Pattern Recognition · Computer Science 2020-09-29 Xiran Wang , Jason Juang , Stanley H. Chan