English
Related papers

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

200 papers

LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides excellent short…

Modern radio telescope surveys, capable of detecting billions of galaxies in wide-field surveys, have made manual morphological classification impracticable. This applies in particular when the Square Kilometre Array Observatory (SKAO)…

Astrophysics of Galaxies · Physics 2026-01-09 Philipp Denzel , Manuel Weiss , Elena Gavagnin , Frank-Peter Schilling

Winged radio sources are a small sub-class of extragalactic radio sources which display a pair of low surface brightness radio lobes, known as `wings' aligned at a certain angle with the primary jets. Depending on the location of wings,…

Astrophysics of Galaxies · Physics 2021-04-02 Sabyasachi Pal , Shobha Kumari

A fraction of galaxy clusters harbor diffuse radio sources known as radio halos. The currently adopted scenario for their formation is based on second-order Fermi re-acceleration of seed electrons that is driven by merger-driven turbulence…

A large fraction of Fermi-Large Area Telescope (LAT) sources in the fourth Fermi-LAT 14 yr catalog (4FGL) still remain unidentified (unIDed). We continued to improve our machine-learning pipeline and used it to classify 1206 X-ray sources…

High Energy Astrophysical Phenomena · Physics 2024-08-20 Hui Yang , Jeremy Hare , Oleg Kargaltsev

Blazars are among the most studied sources in high-energy astrophysics as they form the largest fraction of extragalactic gamma-ray sources and are considered prime candidates for being the counterparts of high-energy astrophysical…

We carry out a shape and weak lensing analysis of Low Frequency Array (LOFAR) radio sources and Hyper Suprime-Cam (HSC) optical sources within the European Large Area Infrared Space Observatory Survey-North 1 (ELAIS-N1) field. Using HSC…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 Jinyi Liu , Reinout van Weeren , Huub Rottgering , Konrad Kuijken

We proposed a machine learning approach to identify and distinguish dusty stellar sources employing supervised and unsupervised methods and categorizing point sources, mainly evolved stars, using photometric and spectroscopic data collected…

We report on optical searches in the error circles of 93 ROSAT survey sources located at low galactic latitudes (|b| < 20 deg). These sources were extracted from the ROSAT Galactic Plane Survey using various selection criteria on hardness…

Lensed quasars are key to many areas of study in astronomy, offering a unique probe into the intermediate and far universe. However, finding lensed quasars has proved difficult despite significant efforts from large collaborations. These…

Vision Transformers are used via a customized TransUNet architecture, which is a hybrid model combining Transformers into a U-Net backbone, to achieve precise, automated, and fast segmentation of radio astronomy data affected by calibration…

Instrumentation and Methods for Astrophysics · Physics 2025-08-14 Nicoletta Sanvitale , Claudio Gheller , Franco Vazza , Annalisa Bonafede , Virginia Cuciti , Emanuele De Rubeis , Federica Govoni , Matteo Murgia , Valentina Vacca

We measure the harmonic-space auto-power spectrum of the galaxy overdensity in the LOFAR Two-metre Sky Survey (LoTSS) First Data Release and its cross correlation with the map of the lensing convergence of the cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-20 David Alonso , Emilio Bellini , Catherine Hale , Matt J. Jarvis , Dominik J. Schwarz

Large-scale sky surveys at low frequencies, like the LOFAR Two-metre Sky Survey (LoTSS), allow for the detection and characterisation of unprecedented numbers of giant radio galaxies (GRGs, or 'giants'). In this work, by automating the…

The Low Frequency Array (LOFAR) is an ideal instrument to conduct deep extragalactic surveys. It has a large field of view and is sensitive to large scale and compact emission. It is, however, very challenging to synthesize thermal noise…

Classification of sources is one of the most important tasks in astronomy. Sources detected in one wavelength band, for example using gamma rays, may have several possible associations in other wavebands, or there may be no plausible…

High Energy Astrophysical Phenomena · Physics 2022-04-19 Aakash Bhat , Dmitry Malyshev

Blazars are radio-loud Active Galactic Nuclei (AGN) whose jets have a very small angle to our line of sight. Observationally, the radio emission are mostly compact or a compact-core with a 1-sided jet. With 2.5$^{\prime\prime}$ resolution…

The Cosmic Lens All-Sky Survey (CLASS) is an international collaborative program which has obtained high-resolution radio images of over 10000 flat-spectrum radio sources in order to create the largest and best studied statistical sample of…

Point source detection at low signal-to-noise is challenging for astronomical surveys, particularly in radio interferometry images where the noise is correlated. Machine learning is a promising solution, allowing the development of…

Instrumentation and Methods for Astrophysics · Physics 2019-04-02 A. Vafaei Sadr , Etienne. E. Vos , Bruce A. Bassett , Zafiirah Hosenie , N. Oozeer , Michelle Lochner

With the availability of multiwavelength, multiscale and multiepoch astronomical catalogues, the number of features to describe astronomical objects has increases. The better features we select to classify objects, the higher the…

Astrophysics · Physics 2009-09-29 Y. Zhang , Y. Zhao , D. Gao