593 citations · 2.5k across the 53 of their papers we have counts for
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Optical and infrared photometry of the blazar PKS0537-441
D. Impiombato, S. Covino, A. Treves +6
We present a large collection of photometric data on the Blazar PKS 0537-441 in the VRIJHK bands taken in 2004-2009. At least three flare-like episodes with months duration, and >3…
The first gamma-ray outburst of a Narrow-Line Seyfert 1 Galaxy: the case of PMN J0948+0022 in July 2010
L. Foschini, G. Ghisellini, Y. Y. Kovalev +24
We report on a multiwavelength campaign on the radio-loud Narrow-Line Seyfert 1 (NLS1) Galaxy PMN J0948+0022 (z=0.5846) performed in 2010 July-September and triggered by a high-ene…
High redshift Fermi blazars
G. Ghisellini, G. Tagliaferri, L. Foschini +6
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 t…
Relativistic jets in Narrow-Line Seyfert 1
L. Foschini, E. Angelakis, G. Bonnoli +20
Narrow-Line Seyfert 1 (NLS1) class of active galactic nuclei (AGNs) is generally radio-quiet, but a small percent of them are radio-loud. The recent discovery by Fermi/LAT of high-…
Does the gamma-ray flux of the blazar 3C 454.3 vary on sub-hour timescales?
L. Foschini, G. Tagliaferri, G. Ghisellini +3
In the early days of April 2010, the blazar 3C 454.3 (z=0.859) underwent a strong gamma-ray outburst, reaching fluxes (E > 100 MeV) in excess of 10^-5 ph cm^-2 s^-1. The Fermi Gamm…
The intergalactic magnetic field constrained by Fermi/LAT observations of the TeV blazar 1ES 0229+200
F. Tavecchio, G. Ghisellini, L. Foschini +3
TeV photons from blazars at relatively large distances, interacting with the optical-IR cosmic background, are efficiently converted into electron-positron pairs. The produced pair…
Correlation of Fermi-LAT sources with the AT20GHz radio survey
G. Ghirlanda, G. Ghisellini, F. Tavecchio +1
We cross correlate the Fermi 11 months survey catalogue (1FGL) with the 20 GHz Australia Telescope Compact Array radio survey catalogue (AT20G) composed by 5890 sources at declinat…
Chasing the heaviest black holes of jetted Active Galactic Nuclei
G. Ghisellini, R. Della Ceca, M. Volonteri +7
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…