English
Related papers

Related papers: Artificial Neural Network Classification of 4FGL S…

200 papers

A majority of blazars exhibit variable emission across the entire electromagnetic spectrum, observed over various time scales. In particular, discernible periodic patterns are detected in the $\gamma$-ray light curves of a few blazars, such…

High Energy Astrophysical Phenomena · Physics 2025-06-18 Alba Rico , A. Domínguez , P. Peñil , M. Ajello , S. Buson , S. Adhikari , M. Movahedifar

This work investigates the multi-wavelength properties of 165 4FGL blazars from the Fermi-LAT fourth source catalogue, looking for with counterparts in the Australian SKA Pathfinder (ASKAP) First Large Absorption Survey in HI (FLASH)…

We are starting a project to find $\gamma$-ray millisecond pulsars (MSPs) among the unidentified sources detected by the Large Area Telescope (LAT) onboard the {Fermi Gamma-Ray Space Telescope (Fermi)}, by radio observations. The selection…

High Energy Astrophysical Phenomena · Physics 2019-03-04 Xuejie Dai , Zhongxiang Wang , Jithesh Vadakkumthani

We present a new catalogue of blazars based on multi-frequency surveys and on an extensive review of the literature. Blazars are classified as BL Lacertae objects, as flat spectrum radio quasars or as blazars of uncertain/transitional type.…

Astrophysics · Physics 2009-11-13 E. Massaro , P. Giommi , C. Leto , P. Marchegiani , A. Maselli , M. Perri , S. Piranomonte , S. Sclavi

Here we report the results of searching millisecond pulsar (MSP) candidates from the Fermi LAT second source catalog (2FGL). Seven unassociated $\gamma-$ray sources in this catalog are identified as promising MSP candidates based on their…

High Energy Astrophysical Phenomena · Physics 2015-08-19 C. Y. Hui , S. M. Park , C. P. Hu , L. C. C. Lin , K. L. Li , A. K. H. Kong , P. H. T. Tam , J. Takata , K. S. Cheng , Ruolan Jin , T. -C. Yen , Chunglee Kim

Using the 100-m Effelsberg radio telescope operating at 1.36 GHz, we have performed a targeted radio pulsar survey of 289 unassociated gamma-ray sources discovered by the Large Area Telescope (LAT) aboard the Fermi satellite and published…

With a decade of gamma-ray data from the Fermi-LAT telescope, we can now hope to answer how well we know the local Universe at gamma-ray frequencies. On the other hand, with gamma-ray data alone it is not possible to directly access the…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-27 Simone Ammazzalorso , Nicolao Fornengo , Shunsaku Horiuchi , Marco Regis

High-redshift radio sources provide plentiful opportunities for studying the formation and evolution of early galaxies and supermassive black holes. However, the number of known radio-loud active galactic nuclei (AGN) above redshift 4 is…

Astrophysics of Galaxies · Physics 2022-06-29 M. Krezinger , K. Perger , K. É. Gabányi , S. Frey , L. I Gurvits , Zs. Paragi , T. An , Y. Zhang , H. Cao , T. Sbarrato

We present a catalog of gamma-ray sources at energies above 10 GeV based on data from the Large Area Telescope (LAT) accumulated during the first three years of the Fermi Gamma-ray Space Telescope mission. The first Fermi-LAT catalog of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 LAT Collaboration

This catalog summarizes 117 high-confidence > 0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT data, through…

High Energy Astrophysical Phenomena · Physics 2013-09-25 LAT collaboration

The study of machine learning (ML) techniques for the autonomous classification of astrophysical sources is of great interest, and we explore its applications in the context of a multifrequency data-frame. We test the use of supervised ML…

High Energy Astrophysical Phenomena · Physics 2020-10-07 Bruno Arsioli , Pedro Dedin

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

We report the results of searching pulsar-like candidates from the unidentified objects in the $3^{\rm rd}$ Catalog of Hard Fermi-LAT sources (3FHL). Using a machine-learning based classification scheme with a nominal accuracy of…

High Energy Astrophysical Phenomena · Physics 2020-05-01 C. Y. Hui , Jongsu Lee , K. L. Li , Sangin Kim , Kwangmin Oh , Shengda Luo , Alex P. Leung , A. K. H. Kong , J. Takata , K. S. Cheng

In our previous work in Xiao et al. (2019), we suggested that 6 superluminal sources could be gamma-ray candidates, and in fact 5 of them have been confirmed in the fourth Fermi-LAT source catalogue (4FGL). In this work, based on the 4FGL,…

High Energy Astrophysical Phenomena · Physics 2020-07-15 Hubing Xiao , Junhui Fan , Riccardo Rando , Jingtian Zhu , Liangjun Hu

About one third of Fermi Large Area Telescope (LAT) sources are unassociated. We perform multi-class classification of Fermi-LAT sources using machine learning with the goal of probabilistic classification of the unassociated sources. A…

High Energy Astrophysical Phenomena · Physics 2025-03-07 Dmitry V. Malyshev

We selected a sample of 437 BL Lac objects, taken from the RomaBZCat catalogue, for which spectroscopic information and SDSS photometry is available. We propose a new classification of BL Lacs in which the sources' type is not defined only…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Enrico Massaro , Roberto Nesci , Silvia Piranomonte

The large majority of sources detected by the Fermi Gamma-ray Space Telescope are blazars, belonging in particular to the blazar subclass of BL Lacertae objects (BL Lacs). BL Lacs often have featureless optical spectra, which make it…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Hermine Landt

In this work, we make use of a supervised machine learning algorithm based on Logistic Regression (LR) to select TeV blazar candidates from the 4FGL-DR2 / 4LAC-DR2, 3FHL, 3HSP, and 2BIGB catalogs. LR constructs a hyperplane based on a…

High Energy Astrophysical Phenomena · Physics 2023-06-28 J. T. Zhu , C. Lin , H. B. Xiao , J. H. Fan , D. Bastieri , G. G. Wang

B2013+370 and B2023+336 are two blazars at low-galactic latitude that were previously proposed to be the counterparts for the EGRET unidentified sources, 3EG J2016+3657 and 3EG J2027+3429. Gamma-ray emission associated with the EGRET…

High Energy Astrophysical Phenomena · Physics 2015-06-03 E. Kara , M. Errando , W. Max-Moerbeck , E. Aliu , M. Bottcher , P. Fortin , J. P. Halpern , R. Mukherjee , A. C. S. Readhead , J. L. Richards

A sample of 312 low-frequency peaked BL Lacertae objects (LBLs) and 694 flat spectrum radio quasars (FSRQs) with the parameters both redshift and $\gamma$-ray photon spectral index ($\Gamma _\gamma$) is compiled from the active galactic…

High Energy Astrophysical Phenomena · Physics 2025-03-31 S. Liang , W. G. Yang , Y. G. Zheng , S. J. Kang