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Related papers: Intermittent radio galaxies and source statistics

200 papers

The time evolution of giant lobe-dominated radio galaxies (with projected linear size D>1 Mpc if H_{0}=50 km/s/Mpc and q_{0}=0.5 is analysed on the basis of dynamical evolution of the entire FRII-type population. Two basic physical…

Astrophysics · Physics 2007-05-23 J. Machalski , K. T. Chyzy , M. Jamrozy

There is mounting evidence that mechanical radio source feedback is important in galaxy evolution and in order to quantify this feedback, detailed models of radio source evolution are required. We present an extension to current analytic…

Astrophysics of Galaxies · Physics 2015-06-19 Tamela Maciel , Paul Alexander

The electron-cyclotron maser instability is widespread in the Universe, producing, e.g., radio emission of the magnetized planets and cool substellar objects. Diagnosing the parameters of astrophysical radio sources requires comprehensive…

Solar and Stellar Astrophysics · Physics 2015-06-04 A. A. Kuznetsov , V. G. Vlasov

Unraveling the origins of radio emissions from radio-quiet active galactic nuclei (RQ AGNs) remains a pivotal challenge in astrophysics. One potential source of this radiation is the shock interaction between AGN disk winds and the…

High Energy Astrophysical Phenomena · Physics 2024-04-09 Tomoya Yamada , Nobuyuki Sakai , Yoshiyuki Inoue , Tomonari Michiyama

We present simultaneous dual-frequency radio observations of Cygnus X-3 during a phase of low-level activity. We constrain the minimum variability timescale to be 20 minutes at 43 GHz and 30 minutes at 15 GHz, implying source sizes of 2 to…

We present some first results on the variability, polarization and general properties of radio sources selected in a blind survey at 20 GHz, the highest frequency at which a sensitive radio survey has been carried out over a large area of…

Infrared-faint radio sources (IFRS) are objects that have flux densities of several mJy at 1.4GHz, but that are invisible at 3.6um when using sensitive Spitzer observations with uJy sensitivities. Their nature is unclear and difficult to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Enno Middelberg , Ray P. Norris , Christopher A. Hales , Nick Seymour , Melanie Johnston-Hollitt , Minh T. Huynh , Emil Lenc , Minnie Y. Mao

Supernovae and their remnants are believed to be prodigious sources of Galactic cosmic rays and interstellar dust. Understanding the mechanisms behind their surprisingly high production rate is helped by the study of nearby young supernova…

High Energy Astrophysical Phenomena · Physics 2015-06-17 L. Staveley-Smith , T. M. Potter , G. Zanardo , B. M. Gaensler , C. -Y. Ng

We present a search for transient and highly variable sources at low radio frequencies (150-200 MHz) that explores long timescales of 1-3 years. We conducted this search by comparing the TIFR GMRT Sky Survey Alternative Data Release 1 (TGSS…

Fast radio bursts (FRBs) are highly dispersed millisecond-duration radio bursts. Recent observations of a Galactic FRB suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here…

Radio observations of the afterglow of the gamma-ray burst GRB970508 provide unique new constraints on afterglow models. The quenching of diffractive scintillation at 4 week delay provides the first direct estimate of source size and…

Astrophysics · Physics 2011-03-17 Eli Waxman , Shri R. Kulkarni , Dale A. Frail

Fast radio bursts (FRBs) are millisecond-duration, bright ($\sim$Jy) extragalactic bursts, whose production mechanism is still unclear. Recently, two repeating FRBs were found to have a physically associated persistent radio source of…

Context. The repeating FRB121102 is so far the only extra-galactic Fast Radio Burst found to be associated with a counterpart, a steady radio source with a nearly flat spectral energy distribution (SED) in centimeter wavelengths. Aims.…

High Energy Astrophysical Phenomena · Physics 2021-12-01 L Resmi , J Vink , C H Ishwara-Chandra

The generally familiar notion that the conservation of energy requires the intensity of the radiation generated by a localized finite-duration source to decay like the inverse square of the distance from the source is not necessarily true.…

Astrophysics · Physics 2009-09-25 H. Ardavan , J. E. Ffowcs Williams

A reexamination of the correspondence between 6 cm radio continuum sources and young star clusters in the Antennae galaxies indicates that 85 % of the strong thermal sources have optical counterparts, once the optical image is shifted 1.2…

Astrophysics · Physics 2009-11-07 B. C. Whitmore , Q. Zhang

According to a generally accepted paradigm, small intrinsic sizes of Compact Steep Spectrum (CSS) radio sources are a direct consequence of their youth, but in later stages of their evolution they are believed to become large-scale sources.…

Astrophysics · Physics 2009-11-13 Andrzej Marecki , Magdalena Kunert-Bajraszewska , Ralph E. Spencer

The Odd Radio Circles are newly identified diffuse radio sources at ~1 GHz frequency, with edge-brightened nearly circular morphology, which is remarkably similar to supernova remnants although a physical association with previous…

High Energy Astrophysical Phenomena · Physics 2022-05-20 Amitesh Omar

Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes. Their physical origin remains unknown, but dozens of possible models have been postulated. Some FRB sources exhibit repeat bursts. Though over a hundred FRB sources…

The universe is filled with a diffuse and isotropic extragalactic background of gamma-ray radiation, containing roughly equal energy flux per decade in photon energy between 3 MeV-100 GeV. The origin of this background is one of the…

Astrophysics · Physics 2011-05-05 Abraham Loeb , Eli Waxman

The contribution of an extent component of source radio emission is estimated for quasars and galaxies. The consideration of source radio structures at kiloparsec scales is used at the decameter and the higher frequency bands. The…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-20 Alla P. Miroshnichenko