Results 101 to 110 of about 23,536 (235)

ROXA: a new multi-frequency selected large sample of blazars with SDSS and 2dF optical spectroscopy

, 2007
Context. Although Blazars are a small fraction of the overall AGN population they are expected to be the dominant population of extragalactic sources in the hard X-ray and gamma-ray bands and have been shown to be the largest contaminant of CMB ...
Abazajian, Adelman-McCarthy, Becker, Bennett, Colless, Condon, E. Cavazzuti, Giommi, Giommi, Gregory, Griffith, Landt, Marchã, McLean, Monet, P. Giommi, Padovani, Perlman, Richards, S. Turriziani, Scarpa, Sowards-Emmerd, Sowards-Emmerd, Sowards-Emmerd, Spergel, Voges, White   +26 more
core   +1 more source

Hunting Very High-energy-emitting (>100 GeV) High-synchrotron-peaked Blazars

The Astrophysical Journal Supplement Series
Very high-energy (VHE; >100 GeV) γ -ray emission originates via some of the most extreme particle acceleration processes in the Universe. Considering beamed active galactic nuclei, i.e., blazars, only a small fraction, mainly high-synchrotron-peaked BL ...
Sushmita Agarwal, Vaidehi S. Paliya
doaj   +1 more source

Sharp Polarimetric Eyes: More Trees than Forest?

Galaxies, 2016
The Fermi Gamma-ray Space Telescope (Fermi) has focused the intensive multi-wavelength and international observational effort on blazars since it was launched in 2008. Part of this effort involves systematic monitoring of the highly variable polarization
Paul S. Smith
doaj   +1 more source

Incidence of MgII absorbers towards Blazars and the GRB/QSO puzzle

, 2010
In order to investigate the origin of the excess of strong MgII systems towards GRB afterglows as compared to QSO sightlines, we have measured the incidence of MgII absorbers towards a third class of objects: the Blazars.
Abdo, Angel, B. Ménard, Bartelmann, Becker, Bergeron, Bergeron, Bergeron, Blades, Choi, Cohen, Collinge, Conselice, Drinkwater, Ellison, Elvis, Falle, Fan, Fan, Fragile, Frank, Gehrels, Giovannini, Hall, Hao, Heidt, Impey, Impey, J. Bergeron, Jannuzi, Kaiser, Kanekar, Komissarov, Londish, Londish, Mellema, Mukherjee, Ménard, Ménard, Narayan, Nestor, P. Boissé, Padovani, Padovani, Pian, Piner, Piner, Plotkin, Pontzen, Porciani, Prochter, Prochter, Rao, Rao, Rector, Sbarufatti, Sbarufatti, Scranton, Smith, Steidel, Steidel, Steidel, Stickel, Stocke, Sudilovsky, Sudilovsky, Tavecchio, Tejos, Tejos, Vergani, Wild, Wolfe, Young   +72 more
core   +2 more sources

Variability of Blazars and Blazar Models over 38 Years [PDF]

Galaxies, 2016
Since 1978, when BL Lac objects and violently variable quasars were married to become “blazars”, physical interpretations of the phenomenon have evolved. Remarkably, though, the general picture of relativistic jets beaming their radiation in our direction, proposed that year by Blandford and Rees, remains intact.
openaire   +2 more sources

Blazars (VLBA & Glast)

, 2003
This review paper discusses the past and present observations of gamma-ray blazars with both space and ground-based gamma-ray telescopes (such as EGRET and current TeV telescopes), and with the VLBA. I also discuss the more sensitive gamma-ray telescopes such as AGILE and GLAST that will become available over the next several years, and how ...
openaire   +2 more sources

Optical Outburst of the Blazar S4 0954+658 in Early 2015

Galaxies, 2016
We analyze the behavior of the BL Lac object S4 0954+658 during an unprecedented bright optical flare in early 2015. The optical flare was accompanied by a powerful γ -ray flare and the detection of very-high-energy γ -ray emission.
Daria Morozova, Valeri Larionov, Svetlana Jorstad, Alan Marscher, Yulia Troitskaya, Ivan Troitskiy, Dmitriy Blinov, Georg Borman, Mark Gurwell   +8 more
doaj   +1 more source

Long-Term Multi-Band and Polarimetric View of Mkn 421: Motivations for an Integrated Open-Data Platform for Blazar Optical Polarimetry

Galaxies, 2017
In this work, by making use of the large software and database resources made available through online facilities such as the ASI Science Data Center (ASDC), we present a novel approach to the modelling of blazar emission whereby the multi-epoch SED for ...
Ulisses Barres de Almeida, Bernardo M. O. Fraga, Paolo Giommi, Narek Sahakyan, Sargis Gasparyan, Carlos H. Brandt   +5 more
doaj   +1 more source

Fermi detected blazars seen by INTEGRAL

, 2009
Multiwavelength observations are essential to constrain physical parameters of the blazars observed by Fermi/LAT. Among the 187 AGN significantly detected in public INTEGRAL data above 20 keV by the imager IBIS/ISGRI, 20 blazars were detected.
Beckmann, V., Ricci, C., Soldi, S.
core   +1 more source

Assigning Degrees of Stochasticity to Blazar Light Curves in the Radio Band Using Complex Networks. [PDF]

Entropy (Basel), 2022
Acosta-Tripailao B, Max-Moerbeck W, Pastén D, Moya PS.   +3 more
europepmc   +1 more source