English
Related papers

Related papers: The blazar sequence revised

200 papers

The extreme variability of blazars, in both timescale and amplitude, is generally explained as the effect of a relativistic jet closely aligned to the observer's line-of-sight. Due to causality arguments, variability characteristics…

We attempt to present a multiwavelength variability and correlation study as well as detailed multi-waveband spectral characteristics of the May 2021 $\gamma$-ray flare of the blazar source TXS 1700+685. The multi-wavelength observation…

High Energy Astrophysical Phenomena · Physics 2022-08-03 Anuvab Banerjee , Prantik Nandi , Raj Prince , Rukaiya Khatoon , Debanjan Bose

We have utilized the largest sample of $\gamma$-ray selected Fermi flat-spectrum radio quasars (FSRQs) ever used (519 sources) to construct the luminosity function and its evolution through the cosmic history. In addition to spanning large…

High Energy Astrophysical Phenomena · Physics 2025-12-02 Garima Rajguru , Lea Marcotulli , Marco Ajello , Mattia Di Mauro , Meg Urry

We present models to predict high frequency counts of extragalactic radio sources using physically grounded recipes to describe the complex spectral behaviour of blazars, that dominate the mm-wave counts at bright flux densities. We show…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Tucci , L. Toffolatti , G. De Zotti , E. Martinez-Gonzalez

Despite their different nature and physics, blazars and gamma-ray bursts have in common very powerful relativistic jets, which make them the most luminous sources in the Universe. The energy extraction from the central compact object, the…

High Energy Astrophysical Phenomena · Physics 2015-12-15 Elena Pian

Flat spectrum radio quasars (FSRQs) are a particular class of blazars rich of optical/ultraviolet photons inside the broad line region (BLR), necessarily implying a huge optical depth for $\gamma$ rays above 20 GeV. As a consequence,…

High Energy Astrophysical Phenomena · Physics 2014-09-16 Giorgio Galanti , Marco Roncadelli , Fabrizio Tavecchio , Giacomo Bonnoli

Observational and theoretical studies point to microquasars (MQs) as possible counterparts of a significant fraction of the unidentified gamma-ray sources detected so far. At present, a proper scenario to explain the emission beyond soft…

Astrophysics · Physics 2009-11-11 V. Bosch-Ramon , G. E. Romero , J. M. Paredes

The high frequency component in blazars is thought to be due to inverse Compton scattered radiation. Recent observations by Fermi-LAT are used to evaluate the details of the scattering process. A comparison is made between the usually…

High Energy Astrophysical Phenomena · Physics 2015-05-19 C. -I. Björnsson

The LAT instrument, onboard the Fermi satellite, in its first three months of operation detected more than 100 blazars at more than the 10 sigma level. This is already a great improvement with respect to its predecessor, the instrument…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-18 G. Ghisellini

Most of the electromagnetic output of blazars (BL Lac objects and Flat Spectrum Radio Quasars) comes out in the gamma-ray band, making the Large Area Telescope [0.1-100 GeV] onboard the Fermi satellite and the Cherenkov telescopes crucial…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 G. Ghisellini

The knowledge of the physical conditions occurring in the relativistic jet of radio-loud active galactic nuclei (AGNs) is important to understand the mechanisms at the basis of their multiband emission. From parsec-scale radio observations…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-29 M. Orienti , G. Giovannini , D. Dallacasa , M. Giroletti , T. Venturi , F. D'Ammando , S. Vercellone , M. Tavani

Blazars host the most powerful persistent relativistic conical jet -- a highly collimated anisotropic flow of material/plasma. Motivated by this, we explore the blazar's broadband spectral energy distribution (SED) in an anisotropic flow of…

High Energy Astrophysical Phenomena · Physics 2021-06-14 Nagendra Kumar , Pankaj Kushwaha

Gamma-ray bursts (GRBs) and GeV-TeV selected radio loud Active Galactic Nuclei (AGNs) are compared based on our systematic modeling of the observed spectral energy distributions of a sample of AGNs with a single-zone leptonic model. We show…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Jin Zhang , En-Wei Liang , Xiao-Na Sun , Bing Zhang , Ye Lu , Shuang-Nan Zhang

We collect the 2LAC and MOJAVE quasi-simultaneous data to investigate the radio-gamma connection of blazars. The cross sample contains 166 sources. The statistic analysis based on this sample confirms positive correlations between these two…

High Energy Astrophysical Phenomena · Physics 2014-09-03 Fan Xu-Liang , Bai Jin-Ming , Liu Hong-Tao , Chen Liang , Liao Neng-Hui

We extend a method for modeling synchrotron and synchrotron self-Compton radiations in blazar jets to include external Compton processes. The basic model assumption is that the blazar radio through soft X-ray flux is nonthermal synchrotron…

Astrophysics · Physics 2009-07-07 Charles D. Dermer , Justin D. Finke , Hannah Krug , Markus Boettcher

The spectral energy distribution and variability of several blazars (Mkn 501, 1 ES 2344+51.4, PKS 2155-30.4, 1 ES 1218+30.4, 3C 454.3) along the blazar sequence is investigated using a selfconsistent and timedependent lepto-hadronic hybrid…

High Energy Astrophysical Phenomena · Physics 2011-09-12 Matthias Weidinger , Felix Spanier

Context: Being dominated by non-thermal emission from aligned relativistic jets, blazars allow us to elucidate the physics of extragalactic jets, and, ltimately, how the energy is extracted from the central black hole in radio-loud active…

We study particle acceleration and radiative processes in Blazar jets under recurring conditions set by gravitational perturbations in supermassive binary systems. We consider the action from a companion orbiting a primary black hole of…

High Energy Astrophysical Phenomena · Physics 2017-03-08 A. Cavaliere , M. Tavani , V. Vittorini

The concept of the evolutionary sequence of jetted active galactic nuclei (AGNs) has been challenged in the last few decades since AGN subclasses are considered to be different due to their viewing angle. In this paper, we collected a…

Astrophysics of Galaxies · Physics 2022-01-26 Evaristus U. Iyida , Christian I. Eze , Finbarr C. Odo

In this study, we conducted a systematic analysis of long-term Fermi-LAT \gamma-ray data for a sample of blazars, including FSRQs, BL\,Lacs, and BCUs, to investigate their $\gamma$-ray variability. We focused on light curves binned in 3-,…