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We propose a new detection technique in the plane based on an isotropic wavelet family. This family is naturally constructed as an extension of the Gaussian-Mexican Hat Wavelet pair and for that reason we call it the Mexican Hat Wavelet…

In this draft we comment on the results concerning the performances of matched filters, scale adaptive filters and Mexican hat wavelet that recently appeared in literature in the context of point source detection in Cosmic Microwave…

Astrophysics · Physics 2009-11-07 Roberto Vio , Paola Andreani , Willelm Wamsteker

In this work we analyze the effect of smoothing maps containing arrival directions of cosmic rays with a gaussian kernel and kernels of the mexican hat wavelets of orders 1, 2 and 3. The analysis is performed by calculating the…

Instrumentation and Methods for Astrophysics · Physics 2012-03-26 Rafael A. Batista , Ernesto Kemp , Rogerio M. de Almeida , Bruno Daniel

It is the aim of this paper to introduce the use of isotropic wavelets to detect and determine the flux of point sources appearing in CMB maps. The most suited wavelet to detect point sources filtered with a Gaussian beam is the Mexican…

The arguments presented by Gonzalez-Nuevo et. al (2006) in favour of the Mexican Hat Wavelet Family (MHWF) are critically discussed here. These authors allege the optimal properties of this new class of filters in the detection of point…

Astrophysics · Physics 2007-05-23 Roberto Vio , Paola Andreani

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

In this work we analyze the effect of smoothing maps containing arrival directions of cosmic rays with a gaussian kernel and kernels of the mexican hat wavelets of orders 1, 2 and 3. The analysis is performed by calculating the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Rafael Alves Batista , Ernesto Kemp , Bruno Daniel

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

Point-source contamination in high-precision Cosmic Microwave Background (CMB) maps severely affects the precision of cosmological parameter estimates. Among the methods that have been proposed for source detection, wavelet techniques based…

Astrophysics · Physics 2009-11-07 R. Vio , L. Tenorio , W. Wamsteker

We present the results of a search for bright high-redshift galaxies in two large SCUBA scan-maps of Galactic regions. A Mexican Hat Wavelet technique was used to locate point sources in these maps, which suffer high foreground…

We study the detection of extragalactic point sources in two-dimensional flat simulations for all the frequencies of the forthcoming ESA's Planck mission. In this work we have used the most recent available templates of the microwave sky:…

We present an estimation of the point source (PS) catalogue that could be extracted from the forthcoming ESA Planck mission data. We have applied the Spherical Mexican Hat Wavelet (SMHW) to simulated all-sky maps that include CMB, Galactic…

Astrophysics · Physics 2009-11-07 P. Vielva , E. Martinez-Gonzalez , J. E. Gallegos , L. Toffolatti , J. L. Sanz

Cosmic microwave background (CMB) temperature anisotropies follow a Gaussian statistical distribution in the standard inflationary model, but there are non-Gaussian contributions due to astrophysical foregrounds. The detection of the…

Astrophysics · Physics 2009-11-11 F. Argueso , J. L. Sanz , R. B. Barreiro , D. Herranz , J. Gonzalez-Nuevo

We present an improved approach for constructing the UV source catalogs using observations from the UltraViolet Imaging Telescope (UVIT) onboard AstroSat, by considering the Poisson distribution of the UV background. The method is tested…

Instrumentation and Methods for Astrophysics · Physics 2025-11-19 B. Ananthamoorthy , Debbijoy Bhattacharya , P. Sreekumar , Swathi B

In this article we consider the detection of compact sources in maps of the Cosmic Microwave Background radiation (CMB) following the philosophy behind the Mexican Hat Wavelet Family (MHWn) of linear filters. We present a new analytical…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 M. López-Caniego , P. Vielva

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

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 a new approach for the identification of ultra-high energy cosmic rays from sources using dynamic graph convolutional neural networks. These networks are designed to handle sparsely arranged objects and to exploit their short-…

High Energy Astrophysical Phenomena · Physics 2020-12-09 Teresa Bister , Martin Erdmann , Jonas Glombitza , Niklas Langner , Josina Schulte , Marcus Wirtz

In this work we address the problem of simultaneous multi-frequency detection of extragalactic point sources in maps of the Cosmic Microwave Background. We apply a new linear filtering technique, the so called `matched matrix filters', that…

Astrophysics · Physics 2009-11-13 D. Herranz , M. Lopez-Caniego , J. L. Sanz , J. Gonzalez-Nuevo

Wavelet-related techniques have proven useful in the processing and analysis of one and two dimensional data sets (spectra in the former case, images in the latter). In this work we apply adaptive filters, introduced in a previous work…

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