Related papers: High redshift Fermi blazars
We study the general physical properties of Fermi blazars using the Fermi fourth source catalog data (4FGL-DR2). The quasi-simultaneous multiwavelength data of Fermi blazar are fitted by using the one-zone leptonic model to obtain some…
I discuss the spectral energy distribution (SED) of all blazars with redshift detected by the {\it Fermi} satellite and listed in the 3LAC catalog. I will update the so called "blazar sequence" from the phenomenological point of view, with…
Blazars are sources whose jet is pointing to us. Since their jets are relativistic, the flux is greatly amplified in the direction of motion, making blazars the most powerful persistent objects in the Universe. This is true at all…
Many blazars detected by the Fermi satellite, observed spectroscopically in the optical, are line-less, and have been classified as BL Lac objects. Optical-UV photometry of nearly one hundred of them allowed to determine the redshift for a…
We present a temporal and spectral analysis of the gamma-ray flux from nine of the brightest flat spectrum radio quasars (FSRQs) detected with the Fermi Large Area Telescope (LAT) during its first eight years of operation, with the aim of…
High redshift blazars are among the most powerful non-explosive sources in the Universe and play a crucial role in understanding the evolution of relativistic jets. To understand these bright objects, we performed a detailed investigation…
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…
The detection of high-redshift ($z>$3) blazars enables the study of the evolution of the most luminous relativistic jets over cosmic time. More importantly, high-redshift blazars tend to host massive black holes and can be used to constrain…
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…
We report on HET and Palomar 5 m spectroscopy of recently identified $\gamma$-ray blazars in the {\it Fermi} LAT Bright Source List. These data provide identifications for 10 newly discovered $\gamma$-ray flat spectrum radio quasars (FSRQ)…
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 use 3 years of data from the Swift/BAT survey to select a complete sample of X-ray blazars above 15 keV. This sample comprises 26 Flat-Spectrum Radio Quasars (FSRQs) and 12 BL Lac objects detected over a redshift range of 0.03<z<4.0. We…
We present the results of a multi-frequency, time-averaged analysis of blazars included in the Candidate Gamma-ray Blazar Survey catalog. Our sample consists of 324 $\gamma$-ray detected ($\gamma$-ray loud) and 191 non $\gamma$-ray detected…
High-redshift ($z >3$) $\gamma$-ray blazars are rare, but they are crucial for our understanding of jet evolution, $\gamma$-ray production and propagation, and the growth of supermassive black holes in the early universe. A new analysis of…
Jet origination is one of the most important questions of AGN, yet it stays obscure. In this work, we made use of information of emission lines, spectral energy distributions (SEDs), \textit{Fermi}-LAT $\gamma$-ray emission, construct a…
Blazars radiate from relativistic jets launched by a supermassive black hole along our line of sight; the subclass of FSRQs exhibits broad emission lines, a telltale sign of a gas-rich environment and high accretion rate, contrary to the…
We investigate the physical properties of the 10 blazars at redshift greater than 2 detected in the 3-years all sky survey performed by the Burst Alert Telescope (BAT) onboard the Swift satellite. We find that the jets of these blazars are…
We report on optical spectroscopy of 165 Flat Spectrum Radio Quasars (FSRQs) in the Fermi 1LAC sample, which have helped allow a nearly complete study of this population. Fermi FSRQ show significant evidence for non-thermal emission even in…
High-redshift blazars are among the most powerful objects in the Universe. The spectral and temporal properties of thirty-three distant blazars ($z>2.5$) detected in the high energy $\gamma$-ray band are investigated by analyzing the {\it…
We revisit the blazar sequence exploiting the complete, flux limited sample of blazars with known redshift detected by the Fermi satellite after 4 years of operations (the 3LAC sample). We divide the sources into gamma-ray luminosity bins,…