English
Related papers

Related papers: Optimizing neural network techniques in classifyin…

200 papers

Machine learning has emerged as a powerful tool in the field of gamma-ray astrophysics. The algorithms can distinguish between different source types, such as blazars and pulsars, and help uncover new insights into the high-energy universe.…

High Energy Astrophysical Phenomena · Physics 2024-01-05 Gopal Bhatta , Sarvesh Gharat , Abhimanyu Borthakur , Aman Kumar

The Fermi Large Area Telescope (LAT) has detected more than 5000 gamma-ray sources in its first 8 years of operation. More than 3000 of them are blazars. About 60 per cent of the Fermi-LAT blazars are classified as BL Lacertae objects (BL…

High Energy Astrophysical Phenomena · Physics 2020-06-22 Miloš Kovačević , Graziano Chiaro , Sara Cutini , Gino Tosti

Since 2008 August the Fermi Large Area Telescope (LAT) has provided continuous coverage of the gamma-ray sky yielding more than 5000 gamma-ray sources, but 54% of the detected sources remain with no certain or unknown association with a low…

High Energy Astrophysical Phenomena · Physics 2020-12-01 Chiaro G. , Kovacevic M. , La Mura G

The Fermi Large Area Telescope (Fermi-LAT) has detected more than 7,000 gamma-ray sources, a significant fraction of which are identified as blazars, while a comparable number remain classified as blazars of uncertain type (BCUs) or are…

High Energy Astrophysical Phenomena · Physics 2026-02-03 Saqlain Afroz , Titir Mukherjee , Raj Prince

The use of Bayesian neural networks is a novel approach for the classification of gamma-ray sources. We focus on the classification of Fermi-LAT blazar candidates, which can be divided into BL Lacertae objects and Flat Spectrum Radio…

High Energy Astrophysical Phenomena · Physics 2022-05-13 Anja Butter , Thorben Finke , Felicitas Keil , Michael Krämer , Silvia Manconi

The Fermi Large Area Telescope (LAT) is currently the most important facility for investigating the GeV $\gamma$-ray sky. With Fermi LAT more than three thousand $\gamma$-ray sources have been discovered so far. 1144 ($\sim40\%$) of the…

High Energy Astrophysical Phenomena · Physics 2016-09-07 G. Chiaro , D. Salvetti , G. La Mura , M. Giroletti , D. J. Thompson , D. Bastieri

The Fermi Gamma-ray Space Telescope is producing the most detailed inventory of the gamma-ray sky to date. Despite tremendous achievements approximately 25% of all Fermi extragalactic sources in the Second Fermi LAT Catalogue (2FGL) are…

High Energy Astrophysical Phenomena · Physics 2012-12-12 T. Hassan , N. Mirabal , J. L. Contreras , I. Oya

The recently published fourth Fermi Large Area Telescope source catalog (4FGL) reports 5065 gamma-ray sources in terms of direct observational gamma-ray properties. Among the sources, the largest population is the Active Galactic Nuclei…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Shi-Ju Kang , Enze Li , Wujing Ou , Kerui Zhu , Jun-Hui Fan , Qingwen Wu , Yue Yin

Machine learning based approaches are emerging as very powerful tools for many applications including source classification in astrophysics research due to the availability of huge high quality data from different surveys in observational…

High Energy Astrophysical Phenomena · Physics 2023-07-05 A. Tolamatti , K. K. Singh , K. K. Yadav

Despite the growing number of gamma-ray sources detected by Fermi-LAT, about one third of the sources in each survey remains of uncertain type. We present a new deep neural network approach for the classification of unidentified or…

High Energy Astrophysical Phenomena · Physics 2021-09-28 Thorben Finke , Michael Krämer , Silvia Manconi

Among the ~2157 unassociated sources in the third data release (DR3) of the fourth Fermi catalog, ~1200 were observed with the Neil Gehrels Swift Observatory pointed instruments. These observations yielded 238 high S/N X-ray sources within…

High Energy Astrophysical Phenomena · Physics 2023-02-15 Amanpreet Kaur , Stephen Kerby , Abraham D. Falcone

We apply a number of statistical and machine learning techniques to classify and rank gamma-ray sources from the Third Fermi Large Area Telescope (LAT) Source Catalog (3FGL), according to their likelihood of falling into the two major…

High Energy Astrophysical Phenomena · Physics 2016-03-23 P. M. Saz Parkinson , H. Xu , P. L. H. Yu , D. Salvetti , M. Marelli , A. D. Falcone

We have investigated a number of factors that can have significant impacts on the classification performance of $\gamma$-ray sources detected by Fermi Large Area Telescope (LAT) with machine learning techniques. We show that a framework of…

Instrumentation and Methods for Astrophysics · Physics 2020-01-29 Shengda Luo , Alex P. Leung , C. Y. Hui , K. L. Li

The latest $\textit{Fermi}$-LAT gamma-ray catalog, 4FGL-DR3, presents a large fraction of sources without clear association to known counterparts, i.e., unidentified sources (unIDs). In this paper, we aim to classify them using machine…

High Energy Astrophysical Phenomena · Physics 2023-04-03 Javier Coronado-Blázquez

In this work, Machine Learning (ML) methods are used to efficiently identify the unassociated sources and the Blazar Candidate of Uncertain types (BCUs) in the Fermi-LAT Third Source Catalog (3FGL). The aims are twofold: 1) to distinguish…

High Energy Astrophysical Phenomena · Physics 2020-05-08 Hubing Xiao , Haitao Cao , Junhui Fan , Denise Costantin , Gaoyong Luo , Zhiyuan Pei

In the third catalog of active galactic nuclei detected by the Fermi-LAT (3LAC) Clean Sample, there are 402 blazars candidates of uncertain type (BCU). Due to the limitations of astronomical observation or intrinsic properties, it is…

High Energy Astrophysical Phenomena · Physics 2019-03-06 Shi-Ju Kang , Junhui Fan , Weiming Mao , Qingwen Wu , Jianchao Feng , Yue Yin

Significant progress in the classification of Fermi unassociated sources , has led to an increasing number of blazars are being found. The optical spectrum is effectively used to classify the blazars into two groups such as BL Lacs and flat…

Instrumentation and Methods for Astrophysics · Physics 2020-06-10 Yijun Xu , Weirong Huang , Hui Deng , Ying Mei , Feng Wang

The Fermi fourth catalog of active galactic nuclei (AGNs) data release 3 (4LAC-DR3) contains 3407 AGNs, out of which 755 are flat spectrum radio quasars (FSRQs), 1379 are BL Lacertae objects (BL Lacs), 1208 are blazars of unknown (BCUs)…

High Energy Astrophysical Phenomena · Physics 2023-04-12 Aditi Agarwal

The deepest all-sky survey available in the $\gamma$-ray band - the last release of the Fermi-LAT catalogue (4FGL-DR3) based on the data accumulated in 12 years, contains more than 6600 sources. The largest population among the sources is…

High Energy Astrophysical Phenomena · Physics 2022-12-28 N. Sahakyan , V. Vardanyan , M. Khachatryan

The Fermi-LAT DR1 and DR2 4FGL catalogues feature more than 5000 gamma-ray sources of which about one fourth are not associated with already known objects, and approximately one third are associated with blazars of uncertain nature. We…

High Energy Astrophysical Phenomena · Physics 2021-06-30 S. Germani , G. Tosti , . Lubrano , S. Cutini , I. Mereu , A. Berretta
‹ Prev 1 2 3 10 Next ›