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Related papers: Modelling the spectral evolution of classical doub…

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We study the emission of X-rays from lobes of FR-II radio galaxies by inverse Compton scattering of microwave background photons. Using a simple model that takes into account injection of relativistic electrons, their energy losses through…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Biman B. Nath

The broad-band spectral distributions of non-thermal sources, such as those of several known blazars, are well described by a log-parabolic fit. The second degree term in these fits measures the curvature in the spectrum. In this paper we…

High Energy Astrophysical Phenomena · Physics 2015-05-28 A. Tramacere , E. Massaro , A. M. Taylor

We present Chandra observations of a small sample of nearby classical double radio galaxies which have more than one radio hotspot in at least one of their lobes. The X-ray emission from the hotspots of these comparatively low-power objects…

Astrophysics · Physics 2009-11-13 M. J. Hardcastle , J. H. Croston , R. P. Kraft

The electron spectrum exhibits a complex structure and has controversially proposed origins. This work reproduce the evolution of the electron spectrum based on a spatially dependent propagation (SDP) model. The key point is that our SPD…

High Energy Physics - Phenomenology · Physics 2025-01-22 Xu-Lin Dong , Shu-Wei Ma , Yi-Qing Guo , Shu-Wang Cui

Solar flares are efficient particle accelerators with a large fraction of released magnetic energy (10-50%) converted into energetic particles such as hard X-ray producing electrons. This energy transfer process is not well constrained,…

Solar and Stellar Astrophysics · Physics 2023-04-12 Morgan Stores , Natasha L. S. Jeffrey , James A. McLaughlin

The prompt emission phase of gamma-ray bursts (GRBs) exhibits two distinct patterns of the peak-energy ($E_p$) evolution, i.e., time-resolved spectral analyses of $\nu F_{\nu}$ spectra of broad pulses reveal (1) "hard-to-soft" and (2)…

High Energy Astrophysical Phenomena · Physics 2018-12-26 Z. Lucas Uhm , Bing Zhang , Judith Racusin

Relativistic and magnetised plasma ejected by radio loud AGNs through jets form the diffuse lobes of radio galaxies. The radiating particles (electron/electron-positron) in lobes emit in radio via the synchrotron process and X-ray via…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-06 C. Konar , M. Jamrozy , M. J. Hardcastle , J. H. Croston , S. Nandi , D. J. Saikia , J. Machalski

The KDA (Kaiser, Dennett-Thorpe & Alexander, 1997) EXT model, that is, the extension of the KDA model of FR (Faranoff & Riley) II-type source evolution, is applied and confronted with the observational data for selected FR II-type radio…

Astrophysics of Galaxies · Physics 2018-04-18 Elżbieta Kuligowska

Determining the energy spectrum of an electron population can give key insights into the underlying physics of a radio source; however, the lack of high resolution, broad-bandwidth observations has left many ambiguities in our understanding…

Astrophysics of Galaxies · Physics 2014-05-01 J. J. Harwood , M. J. Hardcastle , J. H. Croston , A. Stroe , R. Morganti , E. Orru

Extragalactic jets exhibit a wide range of propagation orientations relative to the host galaxy's principal axis. This study investigate the spatiotemporal evolution of jets as a function of their propagation direction within their triaxial…

We describe the pitfalls encountered in deducing from classical double radio source observables (luminosity, spectral index, redshift and linear size) the essential nature of how these objects evolve. We discuss the key role played by…

Astrophysics · Physics 2009-10-31 Katherine Blundell , Steve Rawlings , Chris Willott , Namir Kassim , Rick Perley

There are two different evolution patterns of the peak energy ($E_\text{p}$) exhibited during the prompt emission phase of gamma-ray bursts (GRBs), i.e., hard-to-soft and intensity-tracking, of which the physical origin remains unknown.…

High Energy Astrophysical Phenomena · Physics 2021-12-20 Hao-Xuan Gao , Jin-Jun Geng , Yong-Feng Huang

The characteristics of the spectral evolution of the prompt emission of gamma-ray bursts (GRBs), which are closely related to the radiation mechanism (synchrotron or photosphere), are still an unsolved subject. Here, by performing the…

High Energy Astrophysical Phenomena · Physics 2019-11-12 Liang Li , Jin-Jun Geng , Yan-Zhi Meng , Xue-Feng Wu , Yong-Feng Huang , Yu Wang , Rahim Moradi , Z. Lucas Uhm , Bing Zhang

We present a study of the trends in luminosity, linear size, spectral index, and redshift of classical double radio sources from three complete samples selected at successively fainter low radio-frequency flux-limits. We have been able to…

Astrophysics · Physics 2010-04-06 Katherine M. Blundell , Steve Rawlings , Chris J. Willott

Extremely flat and inverted radio spectra as observed in galactic nuclei and BL Lac sources are still a challenge for fast particle acceleration models. Continuous acceleration by electric fields in reconnection regions can result in almost…

Astrophysics · Physics 2009-11-06 G. T. Birk , A. R. Crusius--Waetzel , H. Lesch

Context. Radio relics in galaxy clusters are known to be good laboratories for verification of the applicability of the diffusive shock acceleration (DSA) model in its canonical version. The need for such verification stems from the…

High Energy Astrophysical Phenomena · Physics 2021-03-17 Grazyna Siemieniec-Ozieblo , Mariia Bilinska

We present a method for applying spatially resolved adiabatic and radiative loss processes to synthetic radio emission from hydrodynamic simulations of radio sources from active galactic nuclei (AGN). Lagrangian tracer particles, each…

High Energy Astrophysical Phenomena · Physics 2022-02-23 Patrick M. Yates-Jones , Ross J. Turner , Stanislav S. Shabala , Martin G. H. Krause

Matched resolution multi-frequency VLA observations of four radio galaxies are used to derive the asymptotic low energy slope of the relativistic electron distribution. Where available, low energy slopes are also determined for other…

Radio relics are diffuse synchrotron sources that illuminate shock waves in the intracluster medium. In recent years, radio telescopes have provided detailed observations about relics. Consequently, cosmological simulations of radio relics…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-02 Denis Wittor , Matthias Hoeft , Marcus Brüggen

We show that a dual-population unification scheme provides a successful paradigm with which to describe the evolution and beaming of all bright extragalactic radio sources. The paradigm consists of two intrinsic radio-source populations,…

Astrophysics · Physics 2009-10-30 C A Jackson , J V Wall