English
Related papers

Related papers: LOFAR search for radio emission from galaxies host…

200 papers

Jellyfish galaxies, characterized by long filaments of stripped interstellar medium extending from their disks, are the prime laboratories to study the outcomes of ram pressure stripping. At radio wavelengths, they often show unilateral…

In recent years, giant amplitude X-ray flares have been observed from a handful of non-active galaxies. The most plausible scenario of these unusual phenomena is tidal disruption of a star by a quiescent supermassive black hole at the…

Many decades of observations of active galactic nuclei and X-ray binaries have shown that relativistic jets are ubiquitous when compact objects accrete. One could therefore anticipate the launch of a jet after a star is disrupted and…

High Energy Astrophysical Phenomena · Physics 2013-03-14 Sjoert van Velzen , Dale A. Frail , Elmar Koerding , Heino Falcke

We discuss possible radio bursts which can be generated during binary neutron stars mergers associated with short gamma-ray bursts. Low-frequency radio band appear to be advantageous due to the time delay of a radio signal propagating in…

High Energy Astrophysical Phenomena · Physics 2010-04-30 K. A. Postnov , M. S. Pshirkov

We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The data were…

High Energy Astrophysical Phenomena · Physics 2016-06-21 A. J. Stewart , R. P. Fender , J. W. Broderick , T. E. Hassall , T. Muñoz-Darias , A. Rowlinson , J. D. Swinbank , T. D. Staley , G. J. Molenaar , B. Scheers , T. L. Grobler , M. Pietka , G. Heald , J. P. McKean , M. E. Bell , A. Bonafede , R. P. Breton , D. Carbone , Y. Cendes , A. O. Clarke , S. Corbel , F. de Gasperin , J. Eislöffel , H. Falcke , C. Ferrari , J. -M. Grießmeier , M. J. Hardcastle , V. Heesen , J. W. T. Hessels , A. Horneffer , M. Iacobelli , P. Jonker , A. Karastergiou , G. Kokotanekov , V. I. Kondratiev , M. Kuniyoshi , C. J. Law , J. van Leeuwen , S. Markoff , J. C. A. Miller-Jones , D. Mulcahy , E. Orru , M. Pandey-Pommier , L. Pratley , E. Rol , H. J. A. Röttgering , A. M. M. Scaife , A. Shulevski , C. A. Sobey , B. W. Stappers , C. Tasse , A. J. van der Horst , S. van Velzen , R. J. van Weeren , R. A. M. J. Wijers , R. Wijnands , M. Wise , P. Zarka , A. Alexov , J. Anderson , A. Asgekar , I. M. Avruch , M. J. Bentum , G. Bernardi , P. Best , F. Breitling , M. Brüggen , H. R. Butcher , B. Ciardi , J. E. Conway , A. Corstanje , E. de Geus , A. Deller , S. Duscha , W. Frieswijk , M. A. Garrett , A. W. Gunst , M. P. van Haarlem , M. Hoeft , J. Hörandel , E. Juette , G. Kuper , M. Loose , P. Maat , R. McFadden , D. McKay-Bukowski , J. Moldon , H. Munk , M. J. Norden , H. Paas , A. G. Polatidis , D. Schwarz , J. Sluman , O. Smirnov , M. Steinmetz , S. Thoudam , M. C. Toribio , R. Vermeulen , C. Vocks , S. J. Wijnholds , O. Wucknitz , S. Yatawatta

In some clusters of galaxies, a diffuse non-thermal emission is present, not obviously associated with any individual galaxy. These sources have been identified as relics, mini-halos, and halos according to their properties and position…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 G. Giovannini , A. Bonafede , L. Feretti , F. Govoni , M. Murgia

Radio halos are extended ($\sim{\rm Mpc}$), steep-spectrum sources found in the central region of dynamically disturbed clusters of galaxies. Only a handful of radio halos have been reported to reside in galaxy clusters with a mass…

Large-amplitude, high-luminosity soft X-ray flares were detected by the ROSAT All-Sky Survey in several galaxies with no evidence of Seyfert activity in their ground-based optical spectra. These flares had the properties predicted for a…

Astrophysics · Physics 2016-08-30 J. P. Halpern , S. Gezari , S. Komossa

LOFAR (Low Frequency Array) is an innovative radio telescope optimized for the frequency range 30-240 MHz. The telescope is realized as a phased aperture array without any moving parts. Digital beam forming allows the telescope to point to…

Remnant radio galaxies represent the final dying phase of radio galaxy evolution, in which the jets are no longer active. Due to their rarity in flux limited samples and the difficulty of identification, this dying phase remains poorly…

We present LOFAR High-Band Array (HBA) observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 square degrees of sky in the frequency range…

Context. Radio halos are megaparsec-scale diffuse radio sources{ mostly} located at the centres of merging galaxy clusters. The common mechanism invoked to explain their origin is the re-acceleration of relativistic particles caused by…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-27 G. Di Gennaro , R. J. van Weeren , R. Cassano , G. Brunetti , M. Brüggen , M. Hoeft , E. Osinga , A. Botteon , V. Cuciti , F. de Gasperin , H. J. A. Röttgering , C. Tasse

The low frequency array (LOFAR), is the first radio telescope designed with the capability to measure radio emission from cosmic-ray induced air showers in parallel with interferometric observations. In the first $\sim 2\,\mathrm{years}$ of…

Instrumentation and Methods for Astrophysics · Physics 2014-06-27 P. Schellart , A. Nelles , S. Buitink , A. Corstanje , J. E. Enriquez , H. Falcke , W. Frieswijk , J. R. Hörandel , A. Horneffer , C. W. James , M. Krause , M. Mevius , O. Scholten , S. ter Veen , S. Thoudam , M. van den Akker , A. Alexov , J. Anderson , I. M. Avruch , L. Bähren , R. Beck , M. E. Bell , P. Bennema , M. J. Bentum , G. Bernardi , P. Best , J. Bregman , F. Breitling , M. Brentjens , J. Broderick , M. Brüggen , B. Ciardi , A. Coolen , F. de Gasperin , E. de Geus , A. de Jong , M. de Vos , S. Duscha , J. Eislöffel , R. A. Fallows , C. Ferrari , M. A. Garrett , J. Grießmeier , T. Grit , J. P. Hamaker , T. E. Hassall , G. Heald , J. W. T. Hessels , M. Hoeft , H. A. Holties , M. Iacobelli , E. Juette , A. Karastergiou , W. Klijn , J. Kohler , V. I. Kondratiev , M. Kramer , M. Kuniyoshi , G. Kuper , P. Maat , G. Macario , G. Mann , S. Markoff , D. McKay-Bukowski , J. P. McKean , J. C. A. Miller-Jones , J. D. Mol , D. D. Mulcahy , H. Munk , R. Nijboer , M. J. Norden , E. Orru , R. Overeem , H. Paas , M. Pandey-Pommier , R. Pizzo , A. G. Polatidis , A. Renting , J. W. Romein , H. Röttgering , A. Schoenmakers , D. Schwarz , J. Sluman , O. Smirnov , C. Sobey , B. W. Stappers , M. Steinmetz , J. Swinbank , Y. Tang , C. Tasse , C. Toribio , J. van Leeuwen , R. van Nieuwpoort , R. J. van Weeren , N. Vermaas , R. Vermeulen , C. Vocks , C. Vogt , R. A. M. J. Wijers , S. J. Wijnholds , M. W. Wise , O. Wucknitz , S. Yatawatta , P. Zarka , A. Zensus

A star that passes too close to a massive black hole will be torn apart by tidal forces. The flare of photons emitted during the accretion of the stellar debris is predicted to be observable and candidates of such events have been observed…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-23 Sjoert van Velzen , Elmar Koerding , Heino Falcke

It has long been known that luminous, ultra-steep spectrum radio sources are preferentially associated with massive galaxies at high redshifts. Here we describe a pilot project directed at such objects, to demonstrate the feasibility and…

Astrophysics of Galaxies · Physics 2023-08-02 C. M. Cordun , R. Timmerman , G. K. Miley , R. J. van Weeren , F. Sweijen , L. K. Morabito , H. J. A. Röttgering

In this paper we present a large sample of jellyfish galaxies in low redshift clusters (z<0.05), identified through 120-168 MHz radio continuum from the LOFAR Two-metre Sky Survey (LoTSS). From a parent sample of 29 X-ray-detected SDSS…

Low-mass ($M_{\rm{500}}<5\times10^{14}{\rm{M_\odot}}$) galaxy clusters have been largely unexplored in radio observations, due to the inadequate sensitivity of existing telescopes. However, the upgraded GMRT (uGMRT) and the Low Frequency…

We investigate the number and type of pulsars that will be discovered with the low-frequency radio telescope LOFAR. We consider different search strategies for the Galaxy, for globular clusters and for other galaxies. We show that a 25-day…

Astrophysics of Galaxies · Physics 2015-05-14 Joeri van Leeuwen , Ben Stappers

Aims. We aim to understand the nature of the diffuse radio emission surrounding the massive galaxy cluster PSZ2 G083.29-31.03, at z=0.412, already known to host a radio halo. Our investigation was triggered by Radio U-Net, a novel machine…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-19 C. Stuardi , A. Botteon , M. Sereno , K. Umetsu , R. Gavazzi , A. Bonafede , C. Gheller

We present the astrometric identification of 80 known radio pulsars as unresolved continuum sources detected at 144 MHz in the second data release of the LOFAR Two-metre Sky Survey (LoTSS DR2), which covers 27% of the Northern hemisphere.…

High Energy Astrophysical Phenomena · Physics 2026-02-18 G. A. C. Rijkers , C. G. Bassa , J. R. Callingham , T. Shimwell