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We present detailed analysis of the two gamma-ray sources,1FGL J1801.3-2322c and 1FGL J1800.5-2359c,that have been found toward the supernova remnant(SNR) W28 with the Large Area Telescope(LAT) on board the Fermi Gamma-ray Space…

High Energy Astrophysical Phenomena · Physics 2016-04-13 LAT Collaboration , A. A. Abdo

Deconvolution of large survey images with millions of galaxies requires to develop a new generation of methods which can take into account a space variant Point Spread Function (PSF) and have to be at the same time accurate and fast. We…

Instrumentation and Methods for Astrophysics · Physics 2020-09-16 Florent Sureau , Alexis Lechat , Jean-Luc Starck

Supernovae (SNe) exploding in a dense circumstellar medium (CSM) are predicted to accelerate cosmic rays in collisionless shocks and emit GeV gamma rays and TeV neutrinos on a time scale of several months. Here we summarize the results of…

High Energy Astrophysical Phenomena · Physics 2015-07-15 A. Franckowiak , K. Murase , E. O. Ofek

We present 0.5-2 keV, 2-8 keV, 4-8 keV, and 0.5-8 keV cumulative and differential number counts (logN-logS) measurements for the recently completed ~4 Ms Chandra Deep Field-South (CDF-S) survey, the deepest X-ray survey to date. We…

Line intensity mapping is emerging as a novel method that can measure the collective intensity fluctuations of atomic/molecular line emission from distant galaxies. Several observational programs with various wavelengths are ongoing and…

Astrophysics of Galaxies · Physics 2021-12-15 Kana Moriwaki , Naoki Yoshida

In order to retrieve cosmological parameters from photometric surveys, we need to estimate the distribution of the photometric redshift in the sky with excellent accuracy. We use and apply three different machine learning methods to…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 Elcio Abdalla , Filipe B. Abdalla , Alessandro Marins , Amilcar Queiroz , Rafael M. Ribeiro , Alex S. C. Souza

Learning to generate a task-aware base learner proves a promising direction to deal with few-shot learning (FSL) problem. Existing methods mainly focus on generating an embedding model utilized with a fixed metric (eg, cosine distance) for…

Computer Vision and Pattern Recognition · Computer Science 2020-12-04 Lei Zhang , Fei Zhou , Wei Wei , Yanning Zhang

We present the first Fermi Large Area Telescope (LAT) catalog of long-term $\gamma$-ray transient sources (1FLT). This comprises sources that were detected on monthly time intervals during the first decade of Fermi-LAT operations. The…

High Energy Astrophysical Phenomena · Physics 2021-09-29 L. Baldini , J. Ballet , D. Bastieri , J. Becerra Gonzalez , R. Bellazzini , A. Berretta , E. Bissaldi , R. D. Blandford , E. D. Bloom , R. Bonino , E. Bottacini , P. Bruel , S. Buson , R. A. Cameron , P. A. Caraveo , E. Cavazzuti , S. Chen , G. Chiaro , D. Ciangottini , S. Ciprini , P. Cristarella Orestano , M. Crnogorcevic , S. Cutini , F. D'Ammando , P. de la Torre Luque , F. de Palma , S. W. Digel , N. Di Lalla , F. Dirirsa , L. Di Venere , A. Domínguez , A. Fiori , H. Fleischhack , A. Franckowiak , Y. Fukazawa , S. Funk , P. Fusco , F. Gargano , D. Gasparrini , S. Germani , N. Giglietto , F. Giordano , M. Giroletti , D. Green , I. A. Grenier , S. Griffin , S. Guiriec , M. Gustafsson , J. W. Hewitt , D. Horan , R. Imazawa , G. Jóhannesson , M. Kerr , D. Kocevski , M. Kuss , S. Larsson , L. Latronico , J. Li , I. Liodakis , F. Longo , F. Loparco , M. N. Lovellette , P. Lubrano , S. Maldera , A. Manfreda , G. Martí-Devesa , H. Matake , M. N. Mazziotta , I. Mereu , M. Meyer , N. Mirabal , W. Mitthumsiri , T. Mizuno , M. E. Monzani , A. Morselli , I. V. Moskalenko , S. Nagasawa , M. Negro , R. Ojha , M. Orienti , E. Orlando , M. Palatiello , V. Paliya , D. Paneque , Z. Pei , M. Persic , M. Pesce-Rollins , V. Petrosian , H. Poon , T. A. Porter , G. Principe , J. L. Racusin , S. Rainò , R. Rando , B. Rani , M. Razzano , S. Razzaque , A. Reimer , O. Reimer , P. M. Saz Parkinson , L. Scotton , D. Serini , C. Sgrò , E. J. Siskind , G. Spandre , P. Spinelli , D. J. Suson , H. Tajima , D. Tak , D. F. Torres , G. Tosti , E. Troja , K. Wood , M. Yassine , G. Zaharijas

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

We present a new approach for the identification of ultra-high energy cosmic rays from sources using dynamic graph convolutional neural networks. These networks are designed to handle sparsely arranged objects and to exploit their short-…

High Energy Astrophysical Phenomena · Physics 2020-12-09 Teresa Bister , Martin Erdmann , Jonas Glombitza , Niklas Langner , Josina Schulte , Marcus Wirtz

Cold dark matter subhalos are expected to populate galaxies in numbers. If dark matter self-annihilates, these objects turn into prime targets for indirect searches, in particular with gamma-ray telescopes. Incidentally, the Fermi-LAT…

High Energy Astrophysical Phenomena · Physics 2022-10-31 Gaétan Facchinetti , Julien Lavalle , Martin Stref

Supernova remnants (SNRs) have been regarded for many decades as the sources of Galactic cosmic rays (CRs) up to a few PeV. However, only with the advent of Fermi-LAT it has been possible to detect - at least in some SNRs - \gamma-rays…

High Energy Astrophysical Phenomena · Physics 2013-03-12 Damiano Caprioli

Studies of Fermi-Large Area Telescope (LAT) data coincident with dwarf spheroidal satellite galaxies (dSphs) of the Milky Way (MW) have put the most stringent constraints on models of annihilating dark matter (DM) with candidate masses in…

High Energy Astrophysical Phenomena · Physics 2026-05-26 A. Circiello , M. Di Mauro , M. Ajello , C. Karwin , A. Drlica-Wagner , M. Á. Sánchez-Conde

We train deep learning models on thousands of galaxy catalogues from the state-of-the-art hydrodynamic simulations of the CAMELS project to perform regression and inference. We employ Graph Neural Networks (GNNs), architectures designed to…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-10 Pablo Villanueva-Domingo , Francisco Villaescusa-Navarro

Weak lensing maps contain information beyond two-point statistics on small scales. Much recent work has tried to extract this information through a range of different observables or via nonlinear transformations of the lensing field. Here…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Arushi Gupta , José Manuel Zorrilla Matilla , Daniel Hsu , Zoltán Haiman

We present a search for spatial extension in high-latitude ($|b|>5^\circ$) sources in recent Fermi point source catalogs. The result is the Fermi High-Latitude Extended Sources Catalog, which provides source extensions (or upper limits…

High Energy Astrophysical Phenomena · Physics 2018-09-13 LAT Collaboration , Jonathan Biteau

In the past decade, deep neural networks (DNNs) came to the fore as the leading machine learning algorithms for a variety of tasks. Their raise was founded on market needs and engineering craftsmanship, the latter based more on trial and…

Machine Learning · Computer Science 2021-04-14 Omry Cohen , Or Malka , Zohar Ringel

Deep neural networks (DNNs) for supervised learning can be viewed as a pipeline of a feature extractor (i.e. last hidden layer) and a linear classifier (i.e. output layer) that is trained jointly with stochastic gradient descent (SGD). In…

Machine Learning · Computer Science 2020-02-28 Xiangrui Li , Deng Pan , Xin Li , Dongxiao Zhu

Employing Fermi-LAT gamma ray observations, several independent groups have found excess extended gamma ray emission at the Galactic center (GC). Both, annihilating dark matter (DM) or a population of $\sim 10^3$ unresolved millisecond…

High Energy Astrophysical Phenomena · Physics 2013-12-12 Chris Gordon , Oscar Macias

With the development of deep learning, supervised learning has frequently been adopted to classify remotely sensed images using convolutional networks (CNNs). However, due to the limited amount of labeled data available, supervised learning…

Computer Vision and Pattern Recognition · Computer Science 2017-11-22 Daoyu Lin , Kun Fu , Yang Wang , Guangluan Xu , Xian Sun