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BLAZ4R and the eROSITA view of z>4 blazars
Tullia Sbarrato, Silvia Belladitta, Julien Wolf +8
We present BLAZ4R, the first living catalog of confirmed blazars, with a focus on the contribution of eROSITA, on board of the Spectrum Roentgen Gamma (SRG) spacecraft. Blaza…
BL Lac host galaxies: how to systematically characterise them in optical-NIR spectroscopy
Gaia Delucchi, Tullia Sbarrato, Giorgio Calderone +3
Host galaxies of Active Galactic Nuclei give crucial information on the interaction between accreting Supermassive Black Holes and their surroundings, and on their common evolution…
The IXPE and multifrequency polarimetric view of the extreme blazars 1ES 1101-232 and RGB J0710+591
Fabrizio Tavecchio, Dawoon E. Kim, Gabriel Emery +53
Multiwavelength polarimetry is a powerful tool to probe magnetic field and flow geometries in the relativistic jets of blazars. In this respect, particularly interesting are the so…
Ultra-extreme high-frequency-peaked BL Lacs: A potential population of MeV synchrotron blazars
A. Sciaccaluga, F. Tavecchio, T. Sbarrato +1
We investigate the potential existence of a new population of BL Lacs, called ultra-extreme high-energy-peaked BL Lacs (UEHBLs), whose synchrotron emission component peaks in the M…
BlazEr1: The eROSITA Blazar Catalog. Blazars and Blazar Candidates in the First eROSITA Survey
S. Haemmerich, A. Gokus, F. McBride +28
Aims. eROSITA, on board the Spectrum Roentgen Gamma (SRG) spacecraft, performed its first X-ray all-sky survey (eRASS1) between December 2019 and June 2020. It detected about 93000…
Supermassive black holes and their surroundings: MeV signatures
Tullia Sbarrato, Marco Ajello, Sara Buson +5
The gravitational potential of supermassive black holes is so powerful that it triggers some of the most intense phenomena in the Universe. Accretion onto these objects and relativ…
NVSS J151002+570243: accretion and spin of a z > 4 Fermi detected blazar
Gabriele Alzati, Tullia Sbarrato, Gabriele Ghisellini
Active galactic nuclei formation and evolution is currently an open puzzle. Their enormous mass is not explainable via sub-Eddington accretion and the frequent presence of relativi…
The High Energy X-ray Probe (HEX-P): the most powerful jets through the lens of a superb X-ray eye
Lea Marcotulli, Marco Ajello, Markus Böttcher +20
A fraction of the active supermassive black holes at the centers of galaxies in our Universe are capable of launching extreme kiloparsec-long relativistic jets. These jets are know…
A search for the afterglows, kilonovae, and host galaxies of two short GRBs: GRB 211106A and GRB 211227A
M. Ferro, R. Brivio, P. D'Avanzo +30
Context: GRB 211106A and GRB 211227A are recent gamma-ray bursts (GRBs) with initial X-ray positions suggesting associations with nearby galaxies (z < 0.7). Their prompt emission c…
Subarcsecond view on the high-redshift blazar GB 1508+5714 by the International LOFAR Telescope
A. Kappes, P. R. Burd, M. Kadler +14
Studies of the most distant AGNs allow us to test our current understanding of the physics present in radio-jetted AGNs across a range of environments. The decrease in apparent lum…
Blazar nature of high-z radio-loud quasars
Tullia Sbarrato, Gabriele Ghisellini, Gianpiero Tagliaferri +3
We report on the Swift/XRT observation and classification of eleven blazar candidates at . These sources were selected as part of a sample of extremely radio-loud quasars, in…
Direct observation of an extended X-ray jet at =6.1
L. Ighina, A. Moretti, F. Tavecchio +6
We report on the direct observation of an extended X-ray jet in the =6.1 radio-loud Active Galactic Nucleus PSO J030947.49+271757.31 from a deep Chandra X-ray observation (128 k…
Jetted radio-quiet quasars at z>5
Tullia Sbarrato, Gabriele Ghisellini, Gabriele Giovannini +1
We report on the JVLA observations of three high redshift Active Galactic Nuclei (AGN), having a black hole mass estimated to be among the largest known. Two of them, SDSS J0100+28…
The disk-torus system in active galactic nuclei: possible evidence of highly spinning black holes
Samuele Campitiello, Annalisa Celotti, Gabriele Ghisellini +1
We study the ratio between the luminosity of the torus and that of the accretion disk, inferred from the relativistic model KERRBB for a sample of approximately 2000 luminosity…
Big and young supermassive black holes in the early Universe
Tullia Sbarrato
Blazars are Active Galactic Nuclei characterized by relativistic jets launched in the vicinity of the central engine (i.e. a supermassive black hole), that are oriented close to ou…
Minute-timescale variability in the X-ray emission of the highest redshift blazar
Alberto Moretti, Gabriele Ghisellini, Alessandro Caccianiga +9
We report on two Chandra observations of the quasar PSO J0309+27, the most distant blazar observed so far (z=6.1), performed eight months apart, in March and November 2020. Previou…
A new panchromatic classification of unclassified Burst Alert Telescope active galactic nuclei
Luca Giuliani, Gabriele Ghisellini, Tullia Sbarrato
We collect data at all frequencies for the new sources classified as unknown active galactic nuclei (AGNs) in the latest Burst Alert Telescope (BAT) all-sky hard X-ray catalog. Foc…
Estimating black hole masses: Accretion disk fitting versus reverberation mapping and single epoch
Samuele Campitiello, Annalisa Celotti, Gabriele Ghisellini +1
We selected a sample of 28 Type 1 AGNs for which a black hole mass has been inferred using the reverberation mapping technique and single epoch scaling relations. All 28 sources sh…
A NuSTAR view of powerful gamma-ray loud blazars
G. Ghisellini, M. L. Perri, G. Costamante +6
We observed with the NuSTAR satellite 3 blazars at z>2, detected in gamma-rays by Fermi/LAT and in the soft X-rays, but not yet observed above 10 keV. The flux and slope of their X…
Black hole mass and spin estimates of the most distant quasars
Samuele Campitiello, Annalisa Celotti, Gabriele Ghisellini +1
We investigate the properties of the most distant quasars ULASJ134208.10+092838.61 (), ULASJ112001.48+064124.3 () and DELSJ003836.10-152723.6 () study…
Science with e-ASTROGAM (A space mission for MeV-GeV gamma-ray astrophysics)
A. De Angelis, V. Tatischeff, I. A. Grenier +248
e-ASTROGAM (enhanced ASTROGAM) is a breakthrough Observatory space mission, with a detector composed by a Silicon tracker, a calorimeter, and an anticoincidence system, dedicated t…
How to constrain mass and spin of supermassive black holes through their disk emission
S. Campitiello, G. Ghisellini, T. Sbarrato +1
We investigate the global properties of the radiation emitted by the accretion disk around Kerr black holes. Using the Kerr blackbody (KERRBB) numerical model, we build an analytic…
QSFit: Automatic analysis of optical AGN spectra
G. Calderone, L. Nicastro, G. Ghisellini +4
We present QSFit, a new software package to automatically perform the analysis of Active Galactic Nuclei (AGN) optical spectra. The software provides luminosity estimates for the A…
Extremes of the jet-accretion power relation of blazars, as explored by NuSTAR
T. Sbarrato, G. Ghisellini, G. Tagliaferri +9
Hard X-ray observations are crucial to study the non-thermal jet emission from high-redshift, powerful blazars. We observed two bright z>2 flat spectrum radio quasars (FSRQs) in ha…