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In this paper we consider the problem of localizing a set of broadband sources from a finite window of measurements. In the case of narrowband sources this can be reduced to the problem of spectral line estimation, where our goal is simply…

Signal Processing · Electrical Eng. & Systems 2022-10-24 Coleman DeLude , Rakshith Sharma , Santhosh Karnik , Christopher Hood , Mark Davenport , Justin Romberg

Extracting sources with low signal-to-noise from maps with structured background is a non-trivial task which has become important in studying the faint end of the submillimetre number counts. In this article we study source extraction from…

As most optical satellites remotely acquire multispectral images (MSIs) with limited spatial resolution, multispectral unmixing (MU) becomes a critical signal processing technology for analyzing the pure material spectra for high-precision…

Image and Video Processing · Electrical Eng. & Systems 2026-03-27 Chia-Hsiang Lin , Si-Sheng Young

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

We present a pilot search for variable and transient sources at 1.4 GHz with the Australian Square Kilometre Array Pathfinder (ASKAP). The search was performed in a 30 deg$^{2}$ area centred on the NGC 7232 galaxy group over 8 epochs and…

The upcoming Square Kilometer Array (SKA) is expected to produce humongous amount of data for undertaking H{\sc i}~science. We have developed an MPI-based {\sc Python} pipeline to deal with the large data efficiently with the present…

Instrumentation and Methods for Astrophysics · Physics 2022-12-28 Abinash Kumar Shaw , Manoj Jagannath , Aishrila Mazumder , Arnab Chakraborty , Narendra Nath Patra , Rajesh Mondal , Samir Choudhuri

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

In this paper we introduce a reliable, fully automated and fast algorithm to detect extended extragalactic radio sources (cluster of galaxies, filaments) in existing and forthcoming surveys (like LOFAR and SKA). The proposed solution is…

Instrumentation and Methods for Astrophysics · Physics 2018-09-11 Claudio Gheller , Franco Vazza , Annalisa Bonafede

This paper introduces an adaptive filtering process based on shrinking wavelet coefficients from the corresponding signal wavelet representation. The filtering procedure considers a threshold method determined by an iterative algorithm…

Methodology · Statistics 2023-07-21 F. M. Bayer , A. J. Kozakevicius , R. J. Cintra

Phased microphone arrays are used widely in the applications for acoustic source localization. Deconvolution approaches such as DAMAS successfully overcome the spatial resolution limit of the conventional delay-and-sum (DAS) beamforming…

Sound · Computer Science 2017-02-14 Wei Ma , Xun Liu

We present a filtering technique that can be applied to individual baselines of wide-bandwidth, wide-field interferometric data to geometrically select regions on the celestial sphere that contain primary calibration sources. The technique…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Aaron R. Parsons , Donald C. Backer

We present an automated, DAOFind-based pipeline developed to reprocess J-band Atlas All Sky Release Survey Images from the Two Micron All Sky Survey (2MASS). By optimizing the detection parameters and implementing a screening procedure that…

Instrumentation and Methods for Astrophysics · Physics 2026-01-27 Zehao Liu , Xiyan Peng , Zhenghong Tang , Zhaoxiang Qi , Shilong Liao , Yong Yu

The new generation radio telescopes, such as the Square Kilometre Array (SKA), are expected to reach sufficient sensitivity and resolution to provide large number densities of resolved faint sources, and therefore to open weak gravitational…

Instrumentation and Methods for Astrophysics · Physics 2022-04-12 Marzia Rivi , Lance Miller

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…

Medical imaging modalities including magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound are essential for accurate diagnosis and treatment planning in modern healthcare. However, noise contamination during image…

Image and Video Processing · Electrical Eng. & Systems 2025-08-22 Asadullah Bin Rahman , Masud Ibn Afjal , Md. Abdulla Al Mamun

A new method for removing point radio sources and other non-Gaussian noise is proposed as a means of improving the accuracy of estimates of the angular power spectrum of the cosmic microwave background (CMB). The main idea of the method is…

Astrophysics · Physics 2009-11-13 Anisa T. Bajkova

We present a new technique for overcoming confusion noise in deep far-infrared \Herschel space telescope images making use of prior information from shorter $\lambda<2$\micron wavelengths. For the deepest images obtained by \Herschels, the…

Astrophysics of Galaxies · Physics 2015-06-17 Mohammadtaher Safarzadeh , Henry C. Ferguson , Yu Lu , Hanae Inami , Rachel S. Somerville

The wavelet transform has been used for numerous studies in astrophysics, including signal--noise periodicity and decomposition as well as the signature of differential rotation in stellar light curves. In the present work, we apply the…

Solar and Stellar Astrophysics · Physics 2010-09-28 D. B. de Freitas , I. de C. Leão , B. L. Canto Martins , J. R. De Medeiros

Analysing extended emission in photometric observations of star-forming regions requires maps free from compact foreground, embedded, and background sources, which can interfere with various techniques used to characterise the interstellar…

Instrumentation and Methods for Astrophysics · Physics 2025-04-02 M. Madarász , G. Marton , I. Gezer , S. Lehner , J. Roquette , M. Audard , D. Hernandez , O. Dionatos

In this article we give an account of a method of smoothing spatial inhomogeneous data sets by using wavelet reconstruction on a regular grid in an auxilliary space onto which the original data is mapped. In a previous paper by the present…

Astrophysics · Physics 2009-10-28 S. Rauzy , M. Lachièze-Rey , R. N. Henriksen