English
Related papers

Related papers: BAT AGN Spectroscopic Survey: XVI. General Physica…

200 papers

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-ray continuum, together with Fermi/LAT data allows us to…

High Energy Astrophysical Phenomena · Physics 2019-07-10 G. Ghisellini , M. L. Perri , G. Costamante , G. Tagliaferri , T. Sbarrato , S. Campitiello , G. Madejski , F. Tavecchio , G. Ghirlanda

The Swift Burst Alert Telescope (BAT) survey of Active Galactic Nuclei (AGN) is providing an unprecedented view of local AGNs (<z> = 0.03) and their host galaxy properties. In this paper, we present an analysis of the optical spectra of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Lisa M. Winter , Karen T. Lewis , Michael Koss , Sylvain Veilleux , Brian Keeney , Richard F. Mushotzky

We present the analysis of 2.1 years of Fermi/LAT data on 491 Seyfert galaxies detected by the Swift/BAT survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi First-year Catalog, are detected. Using…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Stacy H. Teng , Richard F. Mushotzky , Rita M. Sambruna , David S. Davis , Christopher S. Reynolds

In three years of observations since the beginning of nominal science operations in August 2008, the Large Area Telescope (LAT) on board the Fermi Gamma Ray Space Telescope has observed high-energy (>20 MeV) \gamma-ray emission from 35…

High Energy Astrophysical Phenomena · Physics 2015-06-15 LAT Collaboration

We present a multi wavelength analysis of 28 of the most luminous low-redshift narrow-line, ultra-hard X-ray selected active galactic nuclei (AGN) drawn from the 70 month Swift/BAT all-sky survey, with bolometric luminosities of…

We report the results from our analysis of a large set of archival data acquired with the X-ray telescope (XRT) onboard Swift, covering the sky region surrounding objects from the first Fermi Large Area Telescope (LAT) catalogue of…

High Energy Astrophysical Phenomena · Physics 2015-09-16 R. Landi , L. Bassani , J. B. Stephen , N. Masetti , A. Malizia , P. Ubertini

Active galactic nuclei (AGNs) make up about 35 per cent of the more than 250 sources detected in very-high-energy (VHE) gamma rays to date with Imaging Atmospheric Cherenkov Telescopes. Apart from four nearby radio galaxies and two AGNs of…

The X-ray, Ultraviolet, Optical emission from radio-quiet AGNs, black hole binaries, and other compact sources, in general, follow a lognormal flux distribution, a linear rms-flux relation, and a (broken) power-law power spectral densities…

High Energy Astrophysical Phenomena · Physics 2020-03-04 Pankaj Kushwaha , Atreyee Sinha , Ranjeev Misra , K. P. Singh , E. M. de Gouveia Dal Pino

Aims. We use a sample of 83 core-dominated active galactic nuclei (AGN) selected from the MOJAVE (Monitoring of Jets in AGN with VLBA Experiments) radio-flux-limited sample and detected with the Fermi Large Area Telescope (LAT) to study the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 T. G. Arshakian , J. León-Tavares , M. Boettcher , J. Torrealba , V. H. Chavushyan , M. L. Lister , E. Ros , J. A. Zensus

The nature of a substantial percentage (about one fifth) of hard X-ray sources discovered with the BAT instrument onboard the Neil Gehrels Swift Observatory (hereafter Swift) is unknown because of the lack of an identified longer-wavelength…

Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 M. Ajello , D. M. Alexander , J. Greiner , G. M. Madejski , N. Gehrels , D. Burlon

Hard X-ray surveys are an important tool for the study of active galactic nuclei (AGN): they provide almost an unbiased view of absorption in the extragalactic population, allow the study of spectral features such as reflection and high…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Loredana Bassani , M. Molina , A. Malizia , F. Panessa , R. Landi , A. Bazzano , P. Ubertini , A. J. Bird , J. B. Stephen

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…

High Energy Astrophysical Phenomena · Physics 2024-01-29 N. Sahakyan , G. Harutyunyan , S. Gasparyan , D. Israyelyan

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)…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Michael S. Shaw , Roger W. Romani , Stephen E. Healey , Garret Cotter , Peter F. Michelson , Anthony C. S. Readhead

Using blazar light curves from the optical All-Sky Automated Survey for Supernovae (ASAS-SN) and the $\gamma$-ray \textit{Fermi}-LAT telescope, we performed the most extensive statistical correlation study between both bands, using a sample…

High Energy Astrophysical Phenomena · Physics 2023-01-18 T. de Jaeger , B. J. Shappee , C. S. Kochanek , J. T. Hinkle , S. Garrappa , I. Liodakis , A. Franckowiak , K. Z. Stanek , J. F. Beacom , J. L. Prieto

Blazars are the brightest and most abundant persistent sources in the extragalactic gamma-ray sky. Due to their significance, they are often observed across various energy bands to explore potential correlations between emissions at…

High Energy Astrophysical Phenomena · Physics 2024-01-22 P. Giommi , N. Sahakyan , D. Israyelyan , M. Manvelyan

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. Focusing on the 36 sources with measured redshift, we compute…

High Energy Astrophysical Phenomena · Physics 2021-04-07 Luca Giuliani , Gabriele Ghisellini , Tullia Sbarrato

While waiting for new gamma-ray burst detections, the Burst Alert Telescope (BAT) on board Swift covers each day ~50% of the sky in the hard X-ray band (``Survey data''). The large field of view (FOV), high sensitivity and good angular…

Astrophysics · Physics 2009-11-13 F. Senziani , G. Novara , A. De Luca , P. A. Caraveo , T. Belloni , G. F. Bignami

We study a sample of 30 high-redshift blazars ($z>2.5$) by means of spectra and the radiation mechanism with Fermi Large Area Telescope $\gamma$-ray observations spanning 15 years. Three models -- the power law, power law with an…

High Energy Astrophysical Phenomena · Physics 2025-01-27 Fan Wu , Benzhong Dai

The extragalactic $\gamma$-rays sky observed by Fermi-Large Area Telescope (LAT) is dominated by blazars. In the fourth release of the Fermi-LAT Point Source Catalog (4FGL), are sources showing a multifrequency behavior similar to that of…