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Related papers: Gamma-ray emission from globular clusters

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We present the results of a photon cluster search in the gamma-ray sky observed by the Fermi Large Area Telescope, using the new Pass 8 dataset, at energies higher than 10 GeV. By means of the Minimum Spanning Tree (MST) algorithm, we found…

High Energy Astrophysical Phenomena · Physics 2016-11-07 R. Campana , E. Massaro , E. Bernieri

In the last few years, the Fermi-LAT telescope has discovered over a 100 pulsars at energies above 100 MeV, increasing the number of known gamma-ray pulsars by an order of magnitude. In parallel, imaging Cherenkov telescopes, such as MAGIC…

High Energy Astrophysical Phenomena · Physics 2019-08-14 T. Hassan , S. Bonnefoy , M. Lopez , N. Mirabal , J. A. Barrio , J. L. Contreras , R. de los Reyes , E. O. Wilhelmi , B. Rudak

Pulsed emission from almost one hundred millisecond pulsars (MSPs) has been detected in $\gamma$-rays by the Fermi Large-Area Telescope. The global properties of this population remain relatively unconstrained despite many attempts to model…

High Energy Astrophysical Phenomena · Physics 2018-09-25 R. T. Bartels , T. D. P. Edwards , C. Weniger

The majority of galactic gamma rays are produced by interaction of cosmic rays with matter or radiation fields. This results in a diffuse radiation concentrated in the galactic plane where the flux of cosmic rays and the density of material…

Astrophysics · Physics 2009-09-29 R. Fleysher

Gamma-ray photons from young pulsars allow the deepest insight into the properties and interactions of high-energy particles with magnetic and photon fields in a pulsar magnetosphere. Measurements with the Compton Gamma-Ray Observatory have…

Astrophysics · Physics 2009-09-29 Gottfried Kanbach

FERMI (formely GLAST) will shortly provide crucial information on relativistic particles in galaxy clusters. We discuss non-thermal emission in the context of general calculations in which relativistic particles (protons and secondary…

Astrophysics · Physics 2009-02-19 G. Brunetti , P. Blasi , R. Cassano , S. Gabici

Millisecond pulsars (MSPs) are a leading explanation of the Galactic Center excess (GCE) observed in Fermi-LAT data. We constrain this scenario by jointly modeling prompt and inverse-Compton $\gamma$ rays from MSP-injected $e^\pm$ on the…

High Energy Astrophysical Phenomena · Physics 2026-05-27 Jordan Koechler , Pedro De la Torre Luque , Mattia Di Mauro

We present spectra of pulsed gamma-ray emission expected from millisecond pulsars within the framework of polar-cap models. The spectra are a superposition of three components due to curvature (CR), synchrotron (SR), and Compton…

Astrophysics · Physics 2007-05-23 Tomasz Bulik , Bronislaw Rudak

High-energy gamma-ray emission from the Galactic plane above ~100 MeV is composed of three main contributions: diffuse emission from cosmic ray interactions in the interstellar medium, emission from extended sources, such as supernova…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Neronov , D. Malyshev , M. Chernyakova , A. Lutovinov

Very high-energy (VHE; E>100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as pulsar wind nebulae (PWNe), supernova remnants (SNRs), giant molecular clouds, gamma-ray binaries, the Galactic Center,…

High Energy Astrophysical Phenomena · Physics 2015-03-13 P. H. Thomas Tam , Stefan Wagner , Omar Tibolla , Ryan Chaves

Around 160 gamma-ray pulsars were discovered by the Fermi Large Area Telescope (LAT) since 2008. The most energetic of them, 12 objects with emission above 25 GeV, are suitable candidates for the detection with the current and future…

High Energy Astrophysical Phenomena · Physics 2017-08-09 A. Burtovoi , T. Y. Saito , L. Zampieri , T. Hassan

The seven known gamma-ray pulsars represent a very small fraction of the more than 1000 presently known radio pulsars, yet they can give us valuable information about pulsar particle acceleration and energetics. Although the theory of…

Astrophysics · Physics 2007-05-23 Alice K. Harding

The Large Area Telescope (LAT) on the Fermi satellite is the first gamma-ray instrument to discover pulsars directly via their gamma-ray emission. Roughly one third of the 117 gamma-ray pulsars detected by the LAT in its first three years…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Pablo M. Saz Parkinson

The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST), with its improved sensitivity relative to previous generation gamma-ray telescopes, is significantly increasing the number of known gamma-ray sources in…

Astrophysics of Galaxies · Physics 2019-08-13 P. M. Saz Parkinson , M. Dormody , M. Ziegler

Analysing 9 years of Fermi-LAT observations, we recently studied the spectral properties of the prominent globular cluster 47 Tuc (Brown et al. 2018). In particular, we investigated several models to explain the observed gamma-ray emission,…

High Energy Astrophysical Phenomena · Physics 2019-10-23 Anthony M. Brown , Thomas Lacroix , Sheridan Lloyd , Celine Boehm , Paula Chadwick

The Fermi Gamma-ray Observatory discovered about a thousand extragalactic sources emitting energy from 100 MeV to 100 GeV. The majority of these sources belong to the class of blazars characterized by a quasi-featureless optical spectrum…

Astrophysics of Galaxies · Physics 2017-11-02 Simona Paiano , Renato Falomo , Marco Landoni , Aldo Treves , Riccardo Scarpa

The H.E.S.S. very-high-energy (VHE, E > 0.1 TeV) gamma-ray telescope system has discovered a new source, HESS J1747-248. The measured integral flux is (1.2 +/- 0.3) \times 10^-12 cm-2 s-1 above 440 GeV for a power-law photon spectral index…

High Energy Astrophysical Phenomena · Physics 2015-05-28 HESS Collaboration , A. Abramowski , F. Acero , F. Aharonian , A. G. Akhperjanian , G. Anton , A. Balzer , A. Barnacka , U. Barres de Almeida , Y. Becherini , J. Becker , B. Behera , K. Bernloehr , A. Bochow , C. Boisson , J. Bolmont , P. Bordas , J. Brucker , F. Brun , P. Brun , T. Bulik , I. Buesching , S. Carrigan , S. Casanova , M. Cerruti , P. M. Chadwick , A. Charbonnier , R. C. G. Chaves , A. Cheesebrough , L. -M. Chounet , A. C. Clapson , G. Coignet , G. Cologna , J. Conrad , M. Dalton , M. K. Daniel , I. D. Davids , B. Degrange , C. Deil , H. J. Dickinson , A. Djannati-Atai , W. Domainko , L. O'C. Drury , F. Dubois , G. Dubus , K. Dutson , J. Dyks , M. Dyrda , K. Egberts , P. Eger , P. Espigat , L. Fallon , C. Farnier , S. Fegan , F. Feinstein , M. V. Fernandes , A. Fiasson , G. Fontaine , A. Foerster , M. Fuessling , Y. A. Gallant , H. Gast , L. Gerard , D. Gerbig , B. Giebels , J. F. Glicenstein , B. Glueck , P. Goret , D. Goering , S. Haeffner , J. D. Hague , D. Hampf , M. Hauser , S. Heinz , G. Heinzelmann , G. Henri , G. Hermann , J. A. Hinton , A. Hoffmann , W. Hofmann , P. Hofverberg , M. Holler , D. Horns , A. Jacholkowska , O. C. de Jager , C. Jahn , M. Jamrozy , I. Jung , M. A. Kastendieck , K. Katarzynski , U. Katz , S. Kaufmann , D. Keogh , D. Khangulyan , B. Khelifi , D. Klochkov , W. Kluzniak , T. Kneiske , Nu. Komin , K. Kosack , R. Kossakowski , H. Laffon , G. Lamanna , D. Lennarz , T. Lohse , A. Lopatin , C. -C. Lu , V. Marandon , A. Marcowith , J. Masbou , D. Maurin , N. Maxted , T. J. L. McComb , M. C. Medina , J. Mehault , N. Nguyen , R. Moderski , E. Moulin , C. L. Naumann , M. Naumann-Godo , M. de Naurois , D. Nedbal , D. Nekrassov , B. Nicholas , J. Niemiec , S. J. Nolan , S. Ohm , E. de Ona Wilhelmi , B. Opitz , M. Ostrowski , I. Oya , M. Panter , M. Paz Arribas , G. Pedaletti , G. Pelletier , P. -O. Petrucci , S. Pita , G. Puehlhofer , M. Punch , A. Quirrenbach , M. Raue , S. M. Rayner , A. Reimer , O. Reimer , M. Renaud , R. de los Reyes , F. Rieger , J. Ripken , L. Rob , S. Rosier-Lees , G. Rowell , B. Rudak , C. B. Rulten , J. Ruppel , F. Ryde , V. Sahakian , A. Santangelo , R. Schlickeiser , F. M. Schoeck , A. Schulz , U. Schwanke , S. Schwarzburg , S. Schwemmer , M. Sikora , J. L. Skilton , H. Sol , G. Spengler , L. Stawarz , R. Steenkamp , C. Stegmann , F. Stinzing , K. Stycz , I. Sushch , A. Szostek , J. -P. Tavernet , R. Terrier , M. Tluczykont , K. Valerius , C. van Eldik , G. Vasileiadis , C. Venter , J. P. Vialle , A. Viana , P. Vincent , H. J. Voelk , F. Volpe , S. Vorobiov , M. Vorster , S. J. Wagner , M. Ward , R. White , A. Wierzcholska , M. Zacharias , A. Zajczyk , A. A. Zdziarski , A. Zech , H. -S. Zechlin

We investigate the $\gamma$-ray emission from 38 millisecond pulsars using 15 years of Fermi-LAT Pass 8 data in the 0.3--500 GeV range. Off-pulse intervals defined objectively with the Bayesian Blocks algorithm reveal significant off-pulse…

High Energy Astrophysical Phenomena · Physics 2026-02-17 Ming-Yu Lei , Zhao-Qiang Shen , Zi-Qing Xia , Xiaoyuan Huang

In a recent paper Brown et al. (2018) analyze the spectral properties of the globular cluster 47 Tucanae (47 Tuc) using 9 years of Fermi-LAT data. Brown et al. (2018) argue that the emission from 47 Tuc cannot be explained by millisecond…

High Energy Astrophysical Phenomena · Physics 2019-10-02 Richard Bartels , Thomas Edwards

The Large Area Telescope on the Fermi gamma-ray Space Telescope provides unprecedented sensitivity for all-sky monitoring of gamma-ray activity. It has detected a few Galactic sources, including 2 gamma-ray binaries and a microquasar. In…

High Energy Astrophysical Phenomena · Physics 2016-11-15 Sylvain Chaty