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Title: Modeling the Delayed Emission in the 2005 Mkn 501 Very-High-Energy Gamma-Ray Flare

Abstract

Recently, the MAGIC collaboration reported evidence for a delay in the arrival times of photons of different energies during a {gamma}-ray flare from the blazar Markarian 501 on 2005 July 9. We describe the observed delayed high-energy emission by applying a homogeneous synchrotron self-Compton (SSC) model under the assumption that the blob, containing relativistic electrons, was observed in its acceleration phase. This modified SSC model predicts the appearance of a {gamma}-ray flare first at lower energies and subsequently at higher energies. Based on the reported time delay, we predict a delay on the order of 1 h if observed between 10 GeV and 100 GeV, which can be tested in the future by simultaneous flare observations using, e.g., the Fermi Gamma-Ray Telescope and Cerenkov telescopes.

Authors:
 [1];  [2]
  1. University of Lodz, Department of Experimental Physics, PL-90-236 Lodz (Poland)
  2. Max-Planck-Institut fuer Physik, D-80805 Muenchen (Germany)
Publication Date:
OSTI Identifier:
21255165
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1085; Journal Issue: 1; Conference: 4. international meeting on high energy gamma-ray astronomy, Heidelberg (Germany), 7-11 Jul 2008; Other Information: DOI: 10.1063/1.3076705; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ACCELERATION; COSMIC GAMMA SOURCES; ELECTRONS; GAMMA RADIATION; GEV RANGE 10-100; PHOTON EMISSION; PHOTONS; QUASARS; RELATIVISTIC RANGE; SIMULATION; TELESCOPES; TIME DELAY

Citation Formats

Bednarek, Wlodek, and Wagner, Robert. Modeling the Delayed Emission in the 2005 Mkn 501 Very-High-Energy Gamma-Ray Flare. United States: N. p., 2008. Web. doi:10.1063/1.3076705.
Bednarek, Wlodek, & Wagner, Robert. Modeling the Delayed Emission in the 2005 Mkn 501 Very-High-Energy Gamma-Ray Flare. United States. doi:10.1063/1.3076705.
Bednarek, Wlodek, and Wagner, Robert. 2008. "Modeling the Delayed Emission in the 2005 Mkn 501 Very-High-Energy Gamma-Ray Flare". United States. doi:10.1063/1.3076705.
@article{osti_21255165,
title = {Modeling the Delayed Emission in the 2005 Mkn 501 Very-High-Energy Gamma-Ray Flare},
author = {Bednarek, Wlodek and Wagner, Robert},
abstractNote = {Recently, the MAGIC collaboration reported evidence for a delay in the arrival times of photons of different energies during a {gamma}-ray flare from the blazar Markarian 501 on 2005 July 9. We describe the observed delayed high-energy emission by applying a homogeneous synchrotron self-Compton (SSC) model under the assumption that the blob, containing relativistic electrons, was observed in its acceleration phase. This modified SSC model predicts the appearance of a {gamma}-ray flare first at lower energies and subsequently at higher energies. Based on the reported time delay, we predict a delay on the order of 1 h if observed between 10 GeV and 100 GeV, which can be tested in the future by simultaneous flare observations using, e.g., the Fermi Gamma-Ray Telescope and Cerenkov telescopes.},
doi = {10.1063/1.3076705},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1085,
place = {United States},
year = 2008,
month =
}
  • As one of the brightest active blazars in both X-ray and very high energy {gamma}-ray bands, Mrk 501, is very useful for physics associated with jets from active galactic nuclei. The ARGO-YBJ experiment has monitored Mrk 501 for {gamma}-rays above 0.3 TeV since 2007 November. The largest flare since 2005 was observed from 2011 October and lasted until about 2012 April. In this paper, a detailed analysis of this event is reported. During the brightest {gamma}-ray flaring episodes from 2011 October 17 to November 22, an excess of the event rate over 6{sigma} is detected by ARGO-YBJ in the directionmore » of Mrk 501, corresponding to an increase of the {gamma}-ray flux above 1 TeV by a factor of 6.6 {+-} 2.2 from its steady emission. In particular, the {gamma}-ray flux above 8 TeV is detected with a significance better than 4{sigma}. Based on time-dependent synchrotron self-Compton (SSC) processes, the broadband energy spectrum is interpreted as the emission from an electron energy distribution parameterized with a single power-law function with an exponential cutoff at its high-energy end. The average spectral energy distribution for the steady emission is well described by this simple one-zone SSC model. However, the detection of {gamma}-rays above 8 TeV during the flare challenges this model due to the hardness of the spectra. Correlations between X-rays and {gamma}-rays are also investigated.« less
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