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Related papers: A machine learning classifier for LOFAR radio gala…

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We present DECORAS, a deep learning based approach to detect both point and extended sources from Very Long Baseline Interferometry (VLBI) observations. Our approach is based on an encoder-decoder neural network architecture that uses a low…

Instrumentation and Methods for Astrophysics · Physics 2022-07-25 S. Rezaei , J. P. McKean , M. Biehl , A. Javadpour

In the context of radio galaxy classification, most state-of-the-art neural network algorithms have been focused on single survey data. The question of whether these trained algorithms have cross-survey identification ability or can be…

Instrumentation and Methods for Astrophysics · Physics 2019-07-31 Hongming Tang , Anna M. M. Scaife , J. P. Leahy

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

We study a sample of 883 sources detected in a deep Very Large Array survey at 1.4 GHz in the Extended Chandra Deep Field South. The paper focuses on the identification of their optical and infrared (IR) counterparts. We use a likelihood…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 M. Bonzini , V. Mainieri , P. Padovani , K. I. Kellermann , N. Miller , P. Rosati , P. Tozzi , S. Vattakunnel , I. Balestra , W. N. Brandt , B. Luo , Y. Q. Xue

Context. In modern astronomy, machine learning has proved to be efficient and effective to mine the big data from the newesttelescopes. Spectral surveys enable us to characterize millions of objects, while long exposure time observations…

Context. Cosmic rays and magnetic fields are key ingredients in galaxy evolution, regulating both stellar feedback and star formation. Their properties can be studied with low-frequency radio continuum observations, free from thermal…

Extended radio sources are an important minority population in modern deep radio surveys, because they enable detailed investigation of the physics governing radio-emitting regions such as active galaxies and their environments.…

We present a new algorithm designed to improve the signal to noise ratio (SNR) of point and extended source detections in direct imaging data. The novel part of our method is that it finds the linear combination of the science images that…

We positionally match the 6 cm GB6, 20 cm FIRST and NVSS, and 92 cm WENSS radio catalogs and find 16,500 matches in ~3,000 deg2 of sky. Using this unified radio database, we construct radio "color-magnitude-morphology" diagrams and find…

Transient radio signals of astrophysical origin present an avenue for studying the dynamic universe. With the next generation of radio interferometers being planned and built, there is great potential for detecting and studying large…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Cathryn M. Trott , Randall B. Wayth , Jean-Pierre R. Macquart , Steven J. Tingay

We present a detailed study of the cosmic star formation history over $90$ per cent of cosmic time ($0\lesssim z\lesssim4$), using deep, radio continuum observations that probe star formation activity independent of dust. The Low Frequency…

With the advent of deep, all-sky radio surveys, the need for ancillary data to make the most of the new, high-quality radio data from surveys like the Evolutionary Map of the Universe (EMU), GLEAM-X, VLASS and LoTSS is growing rapidly.…

Instrumentation and Methods for Astrophysics · Physics 2023-07-13 Kieran J. Luken , Ray P. Norris , X. Rosalind Wang , Laurence A. F. Park , Ying Guo , Miroslav D. Filipovic

Using radio sources from the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey, and optical counterparts in the Sloan Digital Sky Survey (SDSS), we have identified a large number of galaxy clusters. The radio sources within these…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-03 Joshua D. Wing , Elizabeth L. Blanton

We have compiled a sample of 234 ultra-steep-spectrum (USS) selected radio sources in order to find high-redshift radio galaxies. The sample covers the declination range -40deg < DEC < -30deg in the overlap region between the 1400-MHz NRAO…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 J. J. Bryant , J. W. Broderick , H. M. Johnston , R. W. Hunstead , B. M. Gaensler , C. De Breuck

We present a pilot study on the host galaxy environments of CHIME/FRBs by cross-matching baseband-localised events with the LOFAR Two-metre Sky Survey Data Release 2 (LoTSS DR2) at 144 MHz. Unlike traditional methods reliant on optical…

We consider the statistical problem of catalogue matching from a machine learning perspective with the goal of producing probabilistic outputs, and using all available information. A framework is provided that unifies two existing…

Astrophysics · Physics 2009-11-11 D. J. Rohde , M. R. Gallagher , M. J. Drinkwater , K. A. Pimbblet

We have conducted two pilot surveys for radio pulsars and fast transients with the Low-Frequency Array (LOFAR) around 140 MHz and here report on the first low-frequency fast-radio burst limit and the discovery of two new pulsars. The first…

Novel techniques are indispensable to process the flood of data from the new generation of radio telescopes. In particular, the classification of astronomical sources in images is challenging. Morphological classification of radio galaxies…

Instrumentation and Methods for Astrophysics · Physics 2022-10-10 Janis Kummer , Lennart Rustige , Florian Griese , Kerstin Borras , Marcus Brüggen , Patrick L. S. Connor , Frank Gaede , Gregor Kasieczka , Peter Schleper

Context. The identification of bright QSOs is of great importance to probe the intergalactic medium and address open questions in cosmology. Several approaches have been adopted to find such sources in currently available photometric…

We present the second ROSAT all-sky survey source catalogue, hereafter referred to as the 2RXS catalogue. This is the second publicly released ROSAT catalogue of point-like sources obtained from the ROSAT all-sky survey (RASS) observations…

High Energy Astrophysical Phenomena · Physics 2016-09-30 Th. Boller , M. J. Freyberg , J. Truemper , F. Haberl , W. Voges , K. Nandra
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