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Related papers: Detection/estimation of the modulus of a vector. A…

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We consider a set of M images, whose pixel intensities at a common point can be treated as the components of a M-dimensional vector. We are interested in the estimation of the modulus of such a vector associated to a compact source. For…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-05 F. Argueso , J. L. Sanz , D. Herranz

This paper considers the problem of compact source detection on a Gaussian background in 1D. Two aspects of this problem are considered: the design of the detector and the filtering of the data. Our detection scheme is based on local maxima…

Astrophysics · Physics 2009-11-10 M. Lopez-Caniego , D. Herranz , R. B. Barreiro , J. L. Sanz

Constraining the polarisation properties of extragalactic point sources is a relevant task not only because they are one of the main contaminants for primordial cosmic microwave background B-mode detection if the tensor-to-scalar ratio is…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 J. M. Casas , L. Bonavera , J. González-Nuevo , M. M. Cueli , D. Crespo , E. Goitia , C. González-Gutiérrez , J. D. Santos , M. L. Sánchez , F. J. de Cos

Procedures based on current methods to detect sources in X-ray images are applied to simulated XMM images. All significant instrumental effects are taken into account, and two kinds of sources are considered -- unresolved sources…

Astrophysics · Physics 2009-11-06 I. Valtchanov , M. Pierre , R. Gastaud

The detection of polarized sources in the WMAP 5-year data is a very difficult task. The maps are dominated by instrumental noise and only a handful of sources show up as clear peaks in the Q and U maps. Optimal linear filters applied at…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Lopez-Caniego , M. Massardi , J. Gonzalez-Nuevo , L. Lanz , D. Herranz , G. De Zotti , J. L. Sanz , F. Argueso

(Abridged) We present a new method for detecting and measuring compact sources in conditions of intense, and highly variable, fore/background. While all most commonly used packages carry out the source detection over the signal image, our…

Point Source (PS) detection is an important issue for future Cosmic Microwave Background (CMB) experiments since they are one of the main contaminants to the recovery of CMB signal at small scales. Improving its multifrequency detection…

Instrumentation and Methods for Astrophysics · Physics 2022-02-09 J. M. Casas , J. González-Nuevo , L. Bonavera , D. Herranz , S. L. Suárez Gómez , M. M. Cueli , D. Crespo , J. D. Santos , M. L. Sánchez , F. Sánchez-Lasheras , F. J. de Cos

This article considers the detection of point sources in two dimensional astronomical images. The detection scheme we propose is based on peak statistics. We discuss the example of the detection of far galaxies in Cosmic Microwave…

Astrophysics · Physics 2009-11-10 M. Lopez-Caniego , D. Herranz , J. L. Sanz , R. B. Barreiro

The estimation of the polarization $P$ of extragalactic compact sources in Cosmic Microwave Background images is a very important task in order to clean these images for cosmological purposes -- as, for example, to constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 D. Herranz , F. Argüeso , L. Toffolatti , A. Manjón-García , M. López-Caniego

Detection of templates (e.g., sources) embedded in low-number count Poisson noise is a common problem in astrophysics. Examples include source detection in X-ray images, gamma-rays, UV, neutrinos, and search for clusters of galaxies and…

Instrumentation and Methods for Astrophysics · Physics 2018-04-11 Eran O. Ofek , Barak Zackay

The detection of point-sources in microwave maps is a critical step in the analysis of the Cosmic Microwave Background (CMB) data. If not properly removed, these sources have adverse effects on the estimation of the power-spectrum and/or…

Astrophysics · Physics 2009-07-14 R. Vio , P. Andreani

In this paper we introduce a new linear filtering technique, the so-called matrix filters, that maximizes the signal-to-interference ratio of compact sources of unknown intensity embedded in a set of images by taking into account the…

Astrophysics · Physics 2009-11-13 D. Herranz , J. L. Sanz

We present preliminary results from our on-going study: Comparing and optimizing source detection procedures for XMM images. By constructing realistic spatial and spectral source distributions and ``observing'' these through the XMM Science…

Astrophysics · Physics 2007-05-23 Jesper Rasmussen , Kristian Pedersen , Martin Gotz

Detection of point sources in images is a fundamental operation in astrophysics, and is crucial for constraining population models of the underlying point sources or characterizing the background emission. Standard techniques fall short in…

Instrumentation and Methods for Astrophysics · Physics 2018-02-28 Tansu Daylan , Stephen K. N. Portillo , Douglas P. Finkbeiner

Observations of Cosmic Microwave Background (CMB) B-mode polarization provide a way to probe primordial gravitational waves and test inflationary predictions. Extragalactic point sources become a major source of contamination after…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-16 Yi-Ming Wang , Wen-Zheng Chen , Yang Liu , Si-Yu Li , Hong Li

We present stacking polarized intensity as a means to study the polarization of sources that are too faint to be detected individually in surveys of polarized radio sources. Stacking offers not only high sensitivity to the median signal of…

Astrophysics of Galaxies · Physics 2015-06-19 J. M. Stil , B. W. Keller , S. J. George , A. R. Taylor

Advances in radio spectro-polarimetry offer the possibility to disentangle complex regions where relativistic and thermal plasmas mix in the interstellar and intergalactic media. Recent work has shown that apparently simple Faraday Rotation…

Instrumentation and Methods for Astrophysics · Physics 2018-11-07 Shea Brown , Brandon Bergerud , Allison Costa , B. M. Gaensler , Jacob Isbell , Daniel LaRocca , Ray Norris , Cormac Purcell , Lawrence Rudnick , Xiaohui Sun

This paper considers filters (the Mexican hat wavelet, the matched and the scale-adaptive filters) that optimize the detection/separation of point sources on a background. We make a one-dimensional treatment, we assume that the sources have…

Astrophysics · Physics 2009-11-07 R. B. Barreiro , J. L. Sanz , D. Herranz , E. Martinez-Gonzalez

We calculate the detectability of the polarization of the cosmic microwave background (CMB) as a function of the sky coverage, angular resolution, and instrumental sensitivity for a hypothetical experiment. We consider the gradient…

Astrophysics · Physics 2009-10-31 Andrew H. Jaffe , Marc Kamionkowski , Limin Wang

We present X-sifter, a software package designed for near-optimal detection of sources in X-ray images and other forms of photon images in the Poisson-noise regime. The code is based on the Poisson-noise-matched filter (Ofek & Zackay),…

Instrumentation and Methods for Astrophysics · Physics 2024-12-12 Maayane T. Soumagnac , Eran O. Ofek , Shachar S. Israeli , Guy Nir , Imri A. Dickstein
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