Fast Variability of Tera–Electron Volt γ Rays from the Radio Galaxy M87

  title={Fast Variability of Tera–Electron Volt $\gamma$ Rays from the Radio Galaxy M87},
  author={Felix Aharonian and A. G. Akhperjanian and A. R. Bazer-Bachi and Matthias Beilicke and W. Benbow and David Berge and Konrad Bernl{\"o}hr and Catherine Boisson and O. Bolz and V. Borrel and Ilana M. Braun and A. M. Brown and Rolf B{\"u}hler and I. B{\"u}sching and Svenja Carrigan and Paula M Chadwick and L. M. Chounet and Nicolas Produit and R. Cornils and L Costamante and B. Degrange and Hugh Dickinson and Arache Djannati-Ata{\"i} and Luke O'c. Drury and Guillaume Dubus and Kathrin Egberts and D. Emmanoulopoulos and P. Espigat and Fabrice Feinstein and Enrico Ferrero and A. Fiasson and Gilles Fontaine and S. Funk and S. Funk and Matthias F{\"u}{\ss}ling and Yves A. Gallant and Berrie Giebels and J. F. Glicenstein and Philippe Goret and C. Hadjichristidis and Dominik Hauser and Marcus Hauser and G{\"o}tz Heinzelmann and Gilles Henri and German Hermann and J. A. Hinton and A. Hoffmann and W. Hofmann and M. Holleran and Silke Hoppe and Dieter Horns and A. Jacholkowska and O. C. de Jager and Eckhard Kendziorra and Matthias Kerschhaggl and B. Kh{\'e}lifi and Nu. Komin and Alexander K. Konopelko and K. Kosack and Giovanni Lamanna and I. J. Latham and R. Le Gallou and Anne Lemi{\`e}re and M. Lemoine-Goumard and J.-P. Lenain and Thomas Lohse and J. M. Martin and Olivier Martineau-Huynh and Alexandre Marcowith and Conor Masterson and Gilles Maurin and T. J. L. Mccomb and Emmanuel Moulin and Mathieu de Naurois and Dalibor Nedbal and S. J. Nolan and Aristeidis Noutsos and K. J. Orford and J. L. Osborne and M. Ouchrif and Mike Panter and Guy B. Pelletier and Santiago Pita and Gerd P{\"u}hlhofer and M. Punch and S. Ranchon and B. C. Raubenheimer and Martin Raue and Stephen Mark Rayner and A. Reimer and Joachim Ripken and L. Rob and Lo{\"i}c Rolland and S. Rosier-Lees and Gavin Rowell and Vardan Sahakian and A. Santangelo and Ludovic Sauge and Stefan Schlenker and Reinhard Schlickeiser and R. Schr{\"o}der and U. Schwanke and Stefan Schwarzburg and Stefanie Schwemmer and Andreas Shalchi and H'elene Sol and D. Spangler and Felix Spanier and Riaan Steenkamp and Christian M Stegmann and Giulia Superina and P. H. Thomas Tam and J-P. Tavernet and R. Terrier and Martin Tluczykont and C. van Eldik and Georges Vasileiadis and Christo Venter and J. P. Vialle and Pascal Vincent and H. J. V{\"o}lk and Stefan J. Wagner and Martin J. Ward},
  pages={1424 - 1427}
The detection of fast variations of the tera–electron volt (TeV) (1012 eV) γ-ray flux, on time scales of days, from the nearby radio galaxy M87 is reported. These variations are about 10 times as fast as those observed in any other wave band and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central black hole. We thus can exclude several other sites and processes of the γ-ray production. The observations confirm that TeV γ rays are emitted by… Expand
Gamma-ray emission in radio galaxies, from MeV to TeV
  • E. Torresi
  • Physics
  • Proceedings of the International Astronomical Union
  • 2018
Abstract Thanks to the Fermi λ-ray satellite and the current Imaging Atmospheric Cherenkov Telescopes, radio galaxies have arisen as a new class of high- and very-high energy emitters. The favourableExpand
The giant radio galaxy M 87 is located 16.7 Mpc away and harbours a supermassive black hole in its center. Structures of its relativistic plasma jet are resolved at radio, optical and X–ray energies.Expand
Very-High Energy Processes in Black Hole Magnetosphere: the Case of M87
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M87 is a nearby radio galaxy that has been detected at energies ranging from radio to very high energy (VHE) gamma-rays. Its proximity and its jet, misaligned from the line of sight allow detailedExpand
Radio Galaxies—The TeV Challenge
Over the past decade, our knowledge of the γ -ray sky has been revolutionized by ground- and space-based observatories by detecting photons up to several hundreds of tera-electron volt (TeV)Expand
Interpretation of the Flares of M87 at TeV Energies in the Cloud-Jet Interaction Scenario
Active galactic nuclei with misaligned jets have been recently established as a class of high-energy gamma-ray sources. M87, a nearby representative of this class, shows fast TeV variability onExpand
Synoptic studies of 17 blazars detected in very high-energy γ-rays
Since 2002, the number of detected blazars at γ-ray energies above 100 GeV has more than doubled. I study 17 blazars currently known to emit E > 100 GeV γ-rays. Their intrinsic energy spectra areExpand
Detecting axionlike particles with gamma ray telescopes.
We propose that axionlike particles (ALPs) with a two-photon vertex, consistent with all astrophysical and laboratory bounds, may lead to a detectable signature in the spectra of high-energyExpand


On the Magnetic Field in the Kiloparsec-Scale Jet of Radio Galaxy M87
Several low-power kiloparsec-scale jets in nearby radio galaxies are known for their synchrotron radiation extending up to optical and X-ray photon energies. Here we comment on high-energy γ-rayExpand
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We combined deep Chandra, ROSAT HRI, and XMM-Newton observations of M87 to study the impact of active galactic nucleus (AGN) outbursts on its gaseous atmosphere. Many X-ray features appear to be aExpand
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We present Chandra X-ray monitoring of the M87 jet in 2002, which shows that the intensity of HST-1, an optical knot 08 from the core, increased by a factor of 2 in 116 days and a factor of 4 in 2Expand
The Outburst of HST-1 in the M87 Jet
The X-ray intensity of knot HST-1, 085 from the nucleus of the radio galaxy M87, has increased by more than a factor of 50 during the last 5 yr. The optical increase is similar, and our more limitedExpand