English
Related papers

Related papers: Digital Deblurring of CMB Maps II: Asymmetric Poin…

200 papers

Image deblurring aims to restore the detailed texture information or structures from blurry images, which has become an indispensable step in many computer vision tasks. Although various methods have been proposed to deal with the image…

Computer Vision and Pattern Recognition · Computer Science 2024-10-28 Yanni Zhang , Qiang Li , Miao Qi , Di Liu , Jun Kong , Jianzhong Wang

We have compared the cosmic microwave background (CMB) temperature anisotropy maps made from one-year time ordered data (TOD) streams that simulated observations of the originally planned 100 GHz Planck Low Frequency Instrument (LFI). The…

We present a method of centroiding undersampled point spread functions (PSFs) that may be useful, especially when dithering is not an option. If the profile of the expected PSF is known fairly well through characterization of the telescope…

Instrumentation and Methods for Astrophysics · Physics 2025-03-05 Kevin J. Ludwick , Ashley Mazingo

A major problem in Cosmic Microwave Background (CMB) anisotropy mapping, especially in a total-power mode, is the presence of low-frequency noise in the data streams. If unproperly processed, such low-frequency noise leads to striping in…

Astrophysics · Physics 2009-10-31 B. Revenu , A. Kim , R. Ansari , F. Couchot , J. Delabrouille , J. Kaplan

Accurate astrometry and photometry of saturated and coronagraphic point spread functions (PSFs) are fundamental to both ground- and space-based high contrast imaging projects. For ground-based adaptive optics imaging, differential…

Astrophysics · Physics 2008-11-26 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

Point Spread Function (PSF) modeling is a central part of any astronomy data analysis relying on measuring the shapes of objects. It is especially crucial for weak gravitational lensing, in order to beat down systematics and allow one to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Joel Bergé , Sedona Price , Adam Amara , Jason Rhodes

Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even on a full sky map, point source masks can…

Astrophysics · Physics 2009-11-06 Sudeep Das , Amir Hajian , David N. Spergel

Precise measurement of the angular power spectrum of the Cosmic Microwave Background (CMB) temperature and polarization anisotropy can tightly constrain many cosmological models and parameters. However, accurate measurements can only be…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 S. Mitra , G. Rocha , K. M. Górski , K. M. Huffenberger , H. K. Eriksen , M. A. J. Ashdown , C. R. Lawrence

This paper deals with the detection problem of extragalactic point-sources in multi-frequency, microwave sky maps that will be obtainable in future cosmic microwave background radiation (CMB) experiments with instruments capable of very…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 R. Vio , P. Andreani , E. P. R. G. Ramos , A. da Silva

In experimental microwave maps, point-sources can strongly affect the estimation of the power-spectrum and/or the test of Gaussianity of the Cosmic Microwave Background (CMB) component. As a consequence, their removal from the sky maps…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Elsa Patricia R. G. Ramos , Roberto Vio , Paola Andreani

Spectroastrometry is a technique which has the potential to resolve flux distributions on scales of milliarcseconds. In this study, we examine the application of spectroastrometry to binary point sources which are spatially unresolved due…

Astrophysics · Physics 2009-11-10 John M. Porter , Rene D. Oudmaijer , Debbie Baines

Deconvolution microscopy has been extensively used to improve the resolution of the widefield fluorescent microscopy. Conventional approaches, which usually require the point spread function (PSF) measurement or blind estimation, are…

Machine Learning · Computer Science 2019-04-08 Sungjun Lim , Sang-Eun Lee , Sunghoe Chang , Jong Chul Ye

We introduce a pixel space method to detect dipole modulation or hemispherical power asymmetry in the cosmic microwave background (CMB) polarization. The method relies on the use of squared total polarized flux whose ensemble average picks…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Shamik Ghosh , Pankaj Jain

A point spread function (PSF) describes the distribution of light for a pure point source in an astronomical image due to the optics of the instrument. An accurate PSF is key for deconvolution, point source photometry and source removal.…

Instrumentation and Methods for Astrophysics · Physics 2025-07-28 Ava Polzin

A functional approximation to implement Bayesian source separation analysis is introduced and applied to separation of the Cosmic Microwave Background (CMB) using WMAP data. The approximation allows for tractable full-sky map…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Simon P. Wilson , Jiwon Yoon

Removing the aberrations introduced by the Point Spread Function (PSF) is a fundamental aspect of astronomical image processing. The presence of noise in observed images makes deconvolution a nontrivial task that necessitates the use of…

Instrumentation and Methods for Astrophysics · Physics 2017-05-03 Samuel Farrens , Jean-Luc Starck , Fred Maurice Ngolè Mboula

High-fidelity simulated astronomical images are an important tool in developing and measuring the performance of image-processing algorithms, particularly for high precision measurements of cosmic shear -- correlated distortions of images…

Instrumentation and Methods for Astrophysics · Physics 2024-03-25 Claire-Alice Hébert , Joshua E. Meyers , My H. Do , Patricia R. Burchat , the LSST Dark Energy Science Collaboration

We consider a cosmological model with non-Gaussian initial perturbations, which in principle could be generated in non-standard inflationary scenarios with two or more scalar fields. In particular we focus our attention on the model…

Astrophysics · Physics 2011-05-10 Dmitri Novikov , Jens Schmalzing , Viatcheslav F. Mukhanov

The presence of astrophysical emissions in microwave observations forces us to perform component separation to extract the Cosmic Microwave Background (CMB) signal. However, even in the most optimistic cases, there are still strongly…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-26 C. Gimeno-Amo , E. Martínez-González , R. B. Barreiro

We discuss a new procedure to search for point sources in Cosmic Microwave background maps; in particular, we aim at controlling the so-called False Discovery Rate, which is defined as the expected value of false discoveries among pixels…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-01 Javier Carrón Duque , Alessandro Buzzelli , Yabebal Fantaye , Domenico Marinucci , Armin Schwartzman , Nicola Vittorio