Details

Autor(en) / Beteiligte

• Ackermann, M.
• Asano, K.
• Baldini, L.
• Barbiellini, G.
• Bastieri, D.
• Bellazzini, R.
• Bissaldi, E.
• Blandford, R. D.
• Bloom, E. D.
• Bonino, R.
• Bottacini, E.
• Bruel, P.
• Buehler, R.
• Caliandro, G. A.
• Cameron, R. A.
• Caragiulo, M.
• Caraveo, P. A.
• Cecchi, C.
• Cheung, C. C.
• Chiang, J.
• Chiaro, G.
• Ciprini, S.
• Cohen-Tanugi, J.
• Costanza, F.
• Cutini, S.
• D'Ammando, F.
• Palma, F. de
• Desiante, R.
• Digel, S. W.
• Lalla, N. Di
• Mauro, M. Di
• Venere, L. Di
• Drell, P. S.
• Favuzzi, C.
• Fegan, S. J.
• Ferrara, E. C.
• Fukazawa, Y.
• Gargano, F.
• Gasparrini, D.
• Giglietto, N.
• Giordano, F.
• Grenier, I. A.
• Guillemot, L.
• Guiriec, S.
• Hayashida, M.
• Hays, E.
• Horan, D.
• Jóhannesson, G.
• Kensei, S.
• Kocevski, D.
• Kuss, M.
• Mura, G. La
• Larsson, S.
• Latronico, L.
• Li, J.
• Longo, F.
• Loparco, F.
• Lott, B.
• Lubrano, P.
• Madejski, G. M.
• Magill, J. D.
• Maldera, S.
• Manfreda, A.
• Mayer, M.
• Mazziotta, M. N.
• Michelson, P. F.
• Mirabal, N.
• Mizuno, T.
• Monzani, M. E.
• Morselli, A.
• Moskalenko, I. V.
• Nalewajko, K.
• Negro, M.
• Nuss, E.
• Ohsugi, T.
• Orlando, E.
• Paneque, D.
• Perkins, J. S.
• Pesce-Rollins, M.
• Pivato, G.
• Porter, T. A.
• Principe, G.
• Rando, R.
• Razzano, M.
• Razzaque, S.
• Reimer, A.
• Scargle, J. D.
• Sgrò, C.
• Sikora, M.
• Simone, D.
• Siskind, E. J.
• Spada, F.
• Spinelli, P.
• Stawarz, L.
• Thayer, J. B.
• Thompson, D. J.
• Torres, D. F.
• Troja, E.
• Uchiyama, Y.
• Zimmer, S.

Titel

MINUTE-TIMESCALE >100 MeV γ-RAY VARIABILITY DURING THE GIANT OUTBURST OF QUASAR 3C 279 OBSERVED BY FERMI-LAT IN 2015 JUNE

Ist Teil von

• Astrophysical journal. Letters, 2016-06, Vol.824 (2), p.L20-L20

Ort / Verlag

United States: The American Astronomical Society

Erscheinungsjahr

2016

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• ABSTRACT On 2015 June 16, Fermi-LAT observed a giant outburst from the flat spectrum radio quasar 3C 279 with a peak >100 MeV flux of ∼3.6 × 10−5 photons cm−2 s−1, averaged over orbital period intervals. It is historically the highest γ-ray flux observed from the source, including past EGRET observations, with the γ-ray isotropic luminosity reaching ∼1049 erg s−1. During the outburst, the Fermi spacecraft, which has an orbital period of 95.4 minutes, was operated in a special pointing mode to optimize the exposure for 3C 279. For the first time, significant flux variability at sub-orbital timescales was found in blazar observations by Fermi-LAT. The source flux variability was resolved down to 2-minute binned timescales, with flux doubling times of less than 5 minutes. The observed minute-scale variability suggests a very compact emission region at hundreds of Schwarzschild radii from the central engine in conical jet models. A minimum bulk jet Lorentz factor (Γ) of 35 is necessary to avoid both internal γ-ray absorption and super-Eddington jet power. In the standard external radiation Comptonization scenario, Γ should be at least 50 to avoid overproducing the synchrotron self-Compton component. However, this predicts extremely low magnetization (∼5 × 10−4). Equipartition requires Γ as high as 120, unless the emitting region is a small fraction of the dissipation region. Alternatively, we consider γ rays originating as synchrotron radiation of γe ∼ 1.6 × 106 electrons, in a magnetic field B ∼ 1.3 kG, accelerated by strong electric fields E ∼ B in the process of magnetoluminescence. At such short distance scales, one cannot immediately exclude the production of γ-rays in hadronic processes.