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Related papers: Evaluating the classification of Fermi BCUs from t…

200 papers

We present a systematic reassessment of 5,062 high-Galactic latitude gamma-ray sources from the Fermi-LAT 4FGL-DR4 catalog using Firmamento, a web-based platform for multi-frequency source discovery and analysis. Our goal is to provide an…

Classification of sources is one of the most important tasks in astronomy. Sources detected in one wavelength band, for example using gamma rays, may have several possible associations in other wavebands, or there may be no plausible…

High Energy Astrophysical Phenomena · Physics 2022-04-19 Aakash Bhat , Dmitry Malyshev

We present an incremental version (4FGL-DR4, for Data Release 4) of the fourth Fermi-LAT catalog containing 7194 gamma-ray sources. Based on the first 14 years of science data in the energy range from 50 MeV to 1 TeV, it uses the same…

High Energy Astrophysical Phenomena · Physics 2024-07-25 J. Ballet , P. Bruel , T. H. Burnett , B. Lott , The Fermi-LAT collaboration

Despite the large number of discoveries made recently by Fermi, the origins of the so called unidentified gamma-ray sources remain unknown. The large number of these sources suggests that among them there could be a population that…

High Energy Astrophysical Phenomena · Physics 2015-06-04 F. Massaro , R. D'Abrusco , G. Tosti , M. Ajello , D. Gasparrini , J. E. Grindlay , Howard A. Smith

We present the results of our analysis devoted to the research of sources emitting in the energy bands surveyed by both the Swift-BAT and the Fermi-LAT telescopes. We cross-correlate the Fermi-LAT 1-year point source catalogue (1FGL) of…

High Energy Astrophysical Phenomena · Physics 2015-05-27 A. Maselli , G. Cusumano , E. Massaro , A. Segreto , V. La Parola , A. Tramacere , I. Donnarumma

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed contemporaneously by the Very Long Baseline Array (VLBA). In total, 232 sources were observed with…

Nearly one-third of the gamma-ray sources detected by Fermi are still unidentified, despite significant recent progress in this effort. On the other hand, all the gamma-ray extragalactic sources associated in the second Fermi-LAT catalog…

High Energy Astrophysical Phenomena · Physics 2019-08-19 F. Massaro , R. D'Abrusco , A. Paggi , N. Masetti , M. Giroletti , G. Tosti , Howard A. Smith , S. Funk

Blazars are jet-dominated extragalactic objects characterized by the emission of strongly variable non-thermal radiation across the entire electromagnetic spectrum. Therefore, the study of blazars (and in general of radio loud AGN) through…

High Energy Astrophysical Phenomena · Physics 2019-08-15 C. Monte , S. Raino , F. Gargano , S. Cutini , D. Gasparrini , J. Leon Tavares , G. Polenta

We analyse 77 \textit{Fermi} sources and their potential low-energy counterparts previously proposed in the literature. These sources were classified as active galactic nuclei, mainly blazars, based on optical spectroscopy. The main goals…

High Energy Astrophysical Phenomena · Physics 2025-09-03 Alberto Ulgiati , Paolo Padovani , Paolo Giommi , Simona Paiano , Ciro Pinto

Active Galactic Nuclei (AGNs) are characterized by strong temporal flux density variability across the electromagnetic spectrum, offering insights into the complex physical processes governing accretion and plasma outflows. To…

Astrophysics of Galaxies · Physics 2026-02-25 Lang Cui , Krishna Mohana A , Xin Wang , Ning Chang , Guiping Tan , Xiang Liu

For the duration of the Fermi Gamma-Ray Space Telescope's mission, approximately one-third of the point sources detected have been noted as "unassociated," meaning that they seem to have no known counterpart at any other…

High Energy Astrophysical Phenomena · Physics 2021-08-11 S. Bruzewski , F. K. Schinzel , G. B. Taylor , L. Petrov

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

In this study, we analyze the $\sim 16$ yr Fermi-LAT data of 160 blazars consisting of 92 flat-spectrum radio quasars (FSRQs), 64 BL Lacertae type objects (BL Lacs), and 4 blazar candidates of unknown type objects (BCU), and exhibit their…

High Energy Astrophysical Phenomena · Physics 2025-01-22 Junhao Deng , Yunguo Jiang

We find evidence for large-scale clustering amongst Fermi-selected BL Lac objects but not amongst Fermi-selected FSRQs. Using two-point correlation functions we have investigated the clustering properties of different classes of objects…

High Energy Astrophysical Phenomena · Physics 2021-11-08 M. J. M. Marcha , I. W. A. Browne

We present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), during the first 11 months of the science phase of the mission,…

High Energy Astrophysical Phenomena · Physics 2015-05-18 LAT Collaboration

We searched for gamma-ray blazar candidates among the 382 unidentified hard X-ray sources of the 3rd Palermo BAT Catalog (3PBC) obtained from the analysis of 66 months of SWIFT-BAT survey data and listing 1586 sources. We adopted a recently…

High Energy Astrophysical Phenomena · Physics 2015-06-16 A. Maselli , F. Massaro , G. Cusumano , R. D'Abrusco , V. La Parola , A. Paggi , A. Segreto , Howard A. Smith , G. Tosti

To fully exploit the scientific potential of the Fermi mission, we initiated the F-GAMMA program. Between 2007 and 2015 it was the prime provider of complementary multi-frequency monitoring in the radio regime. We quantify the radio…

The impact of the Fermi Gamma-ray Space Telescope on blazar research is reviewed. This includes a brief description of the Fermi Large Area Telescope, a summary of the various classes of extragalactic sources found in the First Large Area…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Charles D. Dermer

We report the results of our exploratory program carried out with the Southern Astrophysical Research (SOAR) telescope aimed at associating counterparts and establishing the nature of the Fermi Unidentified gamma-ray Sources (UGS). We…

High Energy Astrophysical Phenomena · Physics 2015-06-24 M. Landoni , F. Massaro , A. Paggi , R. D'Abrusco , D. Milisavljevic , N. Masetti , Howard. A. Smith , G. Tosti , L. Chomiuk , J. Strader , C. C. Cheung

The parsec-scale radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been investigated using observations with the Very Long Baseline Array (VLBA). Comparisons between LAT…

High Energy Astrophysical Phenomena · Physics 2012-05-04 J. D. Linford , G. B. Taylor , R. W. Romani , J. F. Helmboldt , A. C. S. Readhead , R. Reeves , J. L. Richards