Related papers: Testing the blazar spectral sequence: X-ray select…
X-ray observations are essential to achieve a deeper understanding of the broadband emission mechanism in blazars. Here, we present a long-term spectral and temporal analysis of X-ray and optical observations of 1E 0229+200 collected with…
Extreme high-frequency peaked BL Lac objects (EHBLs) are blazars which exhibit extremely energetic synchrotron emission. They also feature non-thermal gamma-ray emission whose peak lies in the very high-energy (VHE, E > 100 GeV) range, and…
The physics-determined broadband spectral energy distributions (SEDs) of blazars have been widely used to study the property during their flaring/outburst states, while the non-flaring state takes up most of their lifetime and the general…
In 2023 October-November, the blazar BL Lacertae underwent a very large-amplitude submm outburst. The usual single-zone leptonic model with the lower energy peak of the spectral energy distribution (SED) fit by the synchrotron emission from…
We combined multi-wavelength data for blazars from the Roma-BZCAT catalog and analyzed hundreds of X-ray spectra. We present the fluxes and Spectral Energy Distributions (SEDs), in 12 frequency bands from radio to $\gamma$-rays, for a final…
We present the results of an extensive analysis of the optical, ultraviolet, X-ray and $\gamma$-ray data collected from the observations of the BL Lac objects prototype BL Lacertae carried out over a period of nearly 13 years, between…
We show that a blazar classification in BL Lacs and Flat Spectrum Radio Quasars may not be adequate when it relies solely on the equivalent widths (EWs) of optical lines. In fact, depending on redshift, some strong emission lines can fall…
Nearly 50% of all sources detected by the Fermi Large Area Telescope are classified as blazars or blazar candidates, one of the most elusive classes of active galaxies. Additional blazars can also be hidden within the sample of unidentified…
Both leptonic and hadronic emission processes may contribute to blazar jet emission; which dominates in blazars's high energy emission component remains an open question. Some intermediate synchrotron peaked blazars transition from their…
Single-zone synchrotron self-Compton and external Compton models are widely used to explain broad-band Spectral Energy Distributions (SEDs) of blazars from infrared to gamma-rays. These models bear obvious similarities to the homogeneous…
The infrared properties of blazars can be studied from the statistical point of view with the help of sky surveys, like that provided by the Wide-field Infrared Survey Explorer (WISE) and the Two Micron All Sky Survey (2MASS). However,…
We started a follow-up investigation of the Deep X-ray Radio Blazar Survey objects with declination >-10 deg. We undertook a survey with the EVN at 5GHz to make the first images of a complete sample of weak blazars, aiming at a comparison…
Our understanding of the unification of jetted AGNs has advanced greatly as the size of extragalactic sources increased. In the present paper, based on the large sample of radio sources, we compiled 680 blazars (279 FSRQs and 401 BL Lacs)…
The extragalactic $\gamma$-ray sky is dominated by blazars and their study plays an important role in understanding jet physics, cosmic evolution history and origin of ultra high energy cosmic rays. In this work, we study a large sample of…
We present $\gamma$-ray, X-ray, ultraviolet, optical, and near-infrared light curves of 33 $\gamma$-ray bright blazars over four years that we have been monitoring since 2008 August with multiple optical, ground-based telescopes and the…
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…
We present simultaneous multifrequency radio observations for a complete subsample of 26 XBLs from the Einstein Extended Medium-Sensitivity Survey, obtained with the Very Large Array (VLA). Spectra are computed using fluxes at 20, 6 and 3.6…
We compile from literature the broadband SEDs of twelve TeV blazars observed simultaneously or quasi-simultaneously with Fermi/LAT and other instruments. Two SEDs are available for each of the objects and the state is identified as a low or…
We are presenting a detailed parameter study of the time-dependent electron injection and kinematics and the self-consistent radiation transport in jets of intermediate and low-frequency peaked BL Lac objects. Using a time-dependent,…
The non-thermal spectra of blazars, observed from radio to GeV/TeV gamma-rays, reveal two pronounced components, both produced by radiation by energetic particles. One peaks in the IR - to soft X-ray band, radiating via the synchrotron…