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Related papers: An evolutionary scenario for blazar unification

200 papers

We present the first measurement of the projected correlation function of 485 gamma-ray selected Blazars, divided in 175 BLLacertae (BL Lacs) and 310 Flat Spectrum Radio Quasars (FSRQs) detected in the 2-year all-sky survey by Fermi-Large…

Astrophysics of Galaxies · Physics 2015-06-23 Viola Allevato , Alexis Finoguenov , Nico Cappelluti

The high-luminosity blazar OQ 334 is a leading exponent of the intriguing rare phenomenon of alternating between a flat-spectrum radio quasar (FSRQ) and a BL Lac (BLL) states. Its two optical continuum outbursts observed during the $\sim$…

High Energy Astrophysical Phenomena · Physics 2025-05-23 Krishan Chand , Gopal-Krishna

I study the location of the $\gamma$-ray emission in blazar jets by creating a Compton-scattering approximation valid for all anisotropic radiation fields in the Thomson through Klein-Nishina regimes, which is highly accurate and can speed…

High Energy Astrophysical Phenomena · Physics 2020-03-04 Justin D. Finke

With the release of the first year Fermi catalogue, the number of blazars detected above 100 MeV lying at high redshift has been largely increased. There are 28 blazars at z>2 in the "clean" sample. All of them are Flat Spectrum Radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Ghisellini , G. Tagliaferri , L. Foschini , G. Ghirlanda , F. Tavecchio , R. Della Ceca , F. Haardt , M. Volonteri , N. Gehrels

Multi-Messenger observations and theory of astrophysical objects is fast becoming a critical research area in the astrophysics scientific community. In particular, point-like objects like that of BL Lac, flat spectrum radio quasars (FSRQ),…

High Energy Astrophysical Phenomena · Physics 2024-05-24 Ronald Gamble , Jordan Forman , Amethyst Barnes , Gokul Srinivasaragavan , Isiah Holt , Marvin Jones

We explore the viability of the unification of BL Lacs and FR I radio galaxies by comparing the core emission of radio galaxies with those of BL Lacs of similar extended radio power, taking advantage of the newly measured optical nuclear…

Astrophysics · Physics 2007-05-23 Marco Chiaberge , Annalisa Celotti , Alessandro Capetti , Gabriele Ghisellini

This paper presents a detailed analysis of the temporal and spectral variability of the low-energy peaked BL Lac object S5 0716+714 with a long (~74 ks)X-ray observation performed by XMM-Newton on 2007 September 24-25. The source…

High Energy Astrophysical Phenomena · Physics 2015-05-18 You-Hong Zhang

Fermi-LAT analyses show that the gamma-ray photon spectral indices Gamma_gamma of a large sample of blazars correlate with the vFv peak synchrotron frequency v_s according to the relation Gamma_gamma = d - k log v_s. The same function, with…

High Energy Astrophysical Phenomena · Physics 2015-09-09 Charles D. Dermer , Dahai Yan , Li Zhang , Justin D. Finke , Benoit Lott

We investigate the previously proposed possibility that multi-epoch broadband polarimetry could act as a complement or limited proxy for VLBI observations of blazars, in that the number of polarised emission components in the jet, and some…

Astrophysics of Galaxies · Physics 2019-02-20 C. S. Anderson , S. P. O'Sullivan , G. H. Heald , T. Hodgson , A. Pasetto , B. M. Gaensler

Relativistic jets from accreting supermassive black holes at cosmological distances can be powerful emitters of $\gamma$-rays. However, the precise mechanisms and locations responsible for the dissipation of energy within these jets,…

High Energy Astrophysical Phenomena · Physics 2025-01-03 Sushmita Agarwal , Amit Shukla , Karl Mannheim , Bhargav Vaidya , Biswajit Banerjee

The X-ray spectrum of extreme HBL type blazars is located in the synchrotron branch of the broadband spectral energy distribution (SED), at energies below the peak. A joint fit of the extrapolated X-ray spectra together with a host galaxy…

High Energy Astrophysical Phenomena · Physics 2020-06-10 Alicja Wierzcholska , Stefan Wagner

The gamma-ray emission offers a powerful diagnostic tool to probe jets and their surroundings in flat spectrum radio quasars (FSRQ). In particular, sources emitting at high energies (>10 GeV) give us the strongest constraints. This…

High Energy Astrophysical Phenomena · Physics 2015-06-18 L. Pacciani , F. Tavecchio , I. Donnarumma , A. Stamerra , L. Carrasco , E. Recillas , A. Porras , M. Uemura

Detection of Gamma-ray emission from a class of active galactic nuclei (viz blazars), has been one of the important findings from the Compton Gamma Ray Observatory (CGRO). However, their Gamma-ray luminosity function has not been well…

Astrophysics · Physics 2009-12-17 D. Bhattacharya , P. Sreekumar , R. Mukherjee

High-energy observations of extreme BL Lac objects, such as 1ES0229+200 or 1ES 0347-121, recently focused interest both for blazar and jet physics and for the implication on the extragalactic background light and intergalactic magnetic…

High Energy Astrophysical Phenomena · Physics 2015-12-17 F. Tavecchio , G. Bonnoli

We derive quantitative predictions of the optical and X-ray luminosity functions (LF) for QSs in the redshift range $z<3$. Based on BH paradigm, we investigate how the accretion is controlled by the surrounding structures, as these grow…

Astrophysics · Physics 2009-10-31 A. Cavaliere , V. Vittorini

We present data for 18 blazars observed with ASCA, half of which were also observed contemporaneously with EGRET as parts of multi-wavelength campaigns. The observations show a clear difference in the spectra between three subclasses of…

Astrophysics · Physics 2011-06-21 H. Kubo , T. Takahashi , G. Madejski , M. Tashiro , F. Makino , S. Inoue , F. Takahara

The broadband SEDs of blazars show two distinct components which in leptonic models are associated with synchrotron and SSC emission of highly relativistic electrons. In some sources the SSC component dominates the synchrotron peak by one…

High Energy Astrophysical Phenomena · Physics 2011-06-17 M. Zacharias , R. Schlickeiser

A time-dependent Synchrotron Self Compton model (SSC) which is able to motivate the used electron spectra of many SSC models as a balance of acceleration and radiative losses is introduced. Using stochastic acceleration as well as Fermi-I…

High Energy Astrophysical Phenomena · Physics 2010-08-02 Matthias Weidinger , Felix Spanier

The flat spectrum radio quasar (FSRQ) PKS 0208-512 underwent three outbursts at the optical-near-infrared (OIR) wavelengths during 2008-2011. The second OIR outburst did not have a gamma-ray counterpart despite being comparable in…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Ritaban Chatterjee , Krzysztof Nalewajko , Adam D. Myers

Context. Blazar AO 0235+164, located at redshift z = 0.94, has undergone several sharp multi-spectral-range flaring episodes during the last decades. In particular, the episodes peaking in 2008 and 2015, that received extensive…

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