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Related papers: Radio Galaxy Detection in the Visibility Domain

200 papers

We present a new cluster-finding algorithm based on a combination of the Voronoi Tessellation and Friends-Of-Friends methods. The algorithm utilises probability distribution functions derived from a photometric redshift analysis and is…

Astrophysics · Physics 2007-05-23 Lee Clewley , Caroline van Breukelen , David Bonfield

We propose a new method for identifying active galactic nuclei (AGN) in low mass ($\rm M_*\leq10^{10}M_\odot$) galaxies. This method relies on spectral energy distribution (SED) fitting to identify galaxies whose radio flux density has an…

We demonstrate two new approaches that have been developed to aid the production of future hard X-ray catalogs, and specifically to reduce the reliance on human intervention during the detection of faint excesses in maps that also contain…

High Energy Astrophysical Phenomena · Physics 2022-01-19 V. A. Lepingwell , A. J. Bird , S. R. Gunn

The next generation of observatories will facilitate the discovery of new types of astrophysical transients. The detection of such phenomena, whose characteristics are presently poorly constrained, will hinge on the ability to perform blind…

High Energy Astrophysical Phenomena · Physics 2019-02-15 Iftach Sadeh

We revisit the performance and biases of the two-dimensional approach to galaxy-galaxy lensing. This method exploits the information for the actual positions and ellipticities of source galaxies, rather than using only the ensemble…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-03 Andrej Dvornik , Sebastiaan L. Zoutendijk , Henk Hoekstra , Konrad Kuijken

We describe the process of stacking radio interferometry visibilities to form a deep composite image and its application to the observation of transient phenomena. We apply "visibility stacking" to 46 archival Very Large Array observations…

Solar and Stellar Astrophysics · Physics 2015-05-28 Paul Hancock , Bryan M. Gaensler , Tara Murphy

We introduce a novel machine learning framework for estimating the Bayesian posteriors of morphological parameters for arbitrarily large numbers of galaxies. The Galaxy Morphology Posterior Estimation Network (GaMPEN) estimates values and…

The distribution of galaxies in the Zone of Avoidance (ZoA) is incomplete due to the presence of our own Galaxy. Our research focused on the identification and characterisation of galaxies in the ZoA, using the new near-infrared data from…

Inferring sky surface brightness distributions from noisy interferometric data in a principled statistical framework has been a key challenge in radio astronomy. In this work, we introduce Imaging for Radio Interferometry with Score-based…

Instrumentation and Methods for Astrophysics · Physics 2025-01-07 Noé Dia , M. J. Yantovski-Barth , Alexandre Adam , Micah Bowles , Laurence Perreault-Levasseur , Yashar Hezaveh , Anna Scaife

We propose a machine-learning-based technique to determine the number density of radio sources as a function of their flux density, for use in next-generation radio surveys. The method uses a convolutional neural network trained on…

Instrumentation and Methods for Astrophysics · Physics 2024-01-17 Elisa Todarello , Andre Scaffidi , Marco Regis , Marco Taoso

We present a method for automatic detection and classification of galaxies which includes a novel data-augmentation procedure to make trained models more robust against the data taken from different instruments and contrast-stretching…

Instrumentation and Methods for Astrophysics · Physics 2018-09-07 Roberto E. González , Roberto P. Muñoz , Cristian A. Hernández

We present the results of a novel application of Bayesian modelling techniques, which, although purely data driven, have a physically interpretable result, and will be useful as an efficient data mining tool. We base our studies on the…

Astrophysics · Physics 2009-11-13 L. A. Nolan , M. O. Harva , A Kaban , S. Raychaudhury

While it is well known that galaxies are composites of many emission processes, quantifying the various contributions remains challenging. In this work, we use unsupervised machine learning based clustering algorithms to evaluate the…

Quantifying how the baryonic matter traces the underlying dark matter distribution is key to both understanding galaxy formation and our ability to constrain the cosmological model. Using the cross-correlation function of radio and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 S. N. Lindsay , M. J. Jarvis , K. McAlpine

The measurements of the number density of galaxy-galaxy strong lenses can be used to put statistical constraints on the foreground mass distributions. Dusty galaxies uncovered in submillimeter surveys are particularly useful in this regard…

We present a new method for the reconstruction of Sunyaev-Zel'dovich (SZ) galaxy clusters in future SZ-survey experiments using multiband bolometer cameras such as Olimpo, APEX, or Planck. Our goal is to optimise SZ-Cluster extraction from…

Astrophysics · Physics 2009-11-11 S. Pires , J. B. Juin , D. Yvon , Y. Moudden , S. Anthoine , E. Pierpaoli

We present a maximum-likelihood analysis of galaxy-galaxy lensing effects in galaxy clusters and in the field. The aim is to determine the accuracy and robustness of constraints that can be obtained on galaxy halo properties in both…

Astrophysics · Physics 2009-11-10 Marceau Limousin , Jean Paul Kneib , Priyamvada Natarajan

This work proposes a saliency-based attribution framework to evaluate and compare 10 state-of-the-art explainability methods for deep learning models in astronomy, focusing on the classification of radio galaxy images. While previous work…

Instrumentation and Methods for Astrophysics · Physics 2025-02-25 M. T. Atemkeng , C. Chuma , S. Zaza , C. D. Nunhokee , O. M. Smirnov

Context. Filaments are ubiquitous in the Galaxy, and they host star formation. Detecting them in a reliable way is therefore key towards our understanding of the star formation process. Aims. We explore whether supervised machine learning…

To understand the feedback of black holes on their environment or the acceleration of ultra-high energy cosmic rays in the present cosmic epoch, a systematic, all-sky inventory of radio galaxies in the local universe is needed. Here we…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-23 Sjoert van Velzen , Heino Falcke , Pim Schellart , Nils Nierstenhoefer , Karl-Heinz Kampert
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