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Title: Fermi Gamma-Ray Space Telescope Observations Of Gamma-Ray Outbursts From 3C 454.3 In 2009 December And 2010 April

Abstract

The flat spectrum radio quasar 3C 454.3 underwent an extraordinary outburst in December 2009 when it became the brightest -ray source in the sky for over one week. Its daily flux measured with the Fermi Large Area Telescope at photon energies E > 100 MeV reached F100 = 22 ± 1 × 10 -6 ph cm -2 s -1, representing the highest daily flux of any blazar ever recorded in high-energy -rays. It again became the brightest source in the sky in 2010 April, triggering a pointed-mode observation by Fermi. The correlated -ray temporal and spectral properties during these exceptional events are presented and discussed. The main results show flux variability over time scales less than 3 h and very mild spectral variability with an indication of gradual hardening preceding major flares. No consistent loop pattern emerged in the -ray spectral index vs flux plane. A minimum Doppler factor of ≈15 is derived, and the maximum energy of a photon from 3C 454.3 is ≈ 20 GeV. The spectral break at a few GeV is inconsistent with Klein-Nishina softening from power-law electrons scattering Lyα line radiation, and a break in the underlying electron spectrum in blazar leptonic models is implied.

Authors:
 [1]
  1. SLAC National Accelerator Lab., Menlo Park, CA (United States); et al.
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
Fermmi LAT Collaboration
OSTI Identifier:
1357526
Grant/Contract Number:  
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 721; Journal Issue: 2; Journal ID: ISSN 0004-637X
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Ackermann, M. Fermi Gamma-Ray Space Telescope Observations Of Gamma-Ray Outbursts From 3C 454.3 In 2009 December And 2010 April. United States: N. p., 2010. Web. doi:10.1088/0004-637X/721/2/1383.
Ackermann, M. Fermi Gamma-Ray Space Telescope Observations Of Gamma-Ray Outbursts From 3C 454.3 In 2009 December And 2010 April. United States. doi:10.1088/0004-637X/721/2/1383.
Ackermann, M. Thu . "Fermi Gamma-Ray Space Telescope Observations Of Gamma-Ray Outbursts From 3C 454.3 In 2009 December And 2010 April". United States. doi:10.1088/0004-637X/721/2/1383. https://www.osti.gov/servlets/purl/1357526.
@article{osti_1357526,
title = {Fermi Gamma-Ray Space Telescope Observations Of Gamma-Ray Outbursts From 3C 454.3 In 2009 December And 2010 April},
author = {Ackermann, M.},
abstractNote = {The flat spectrum radio quasar 3C 454.3 underwent an extraordinary outburst in December 2009 when it became the brightest -ray source in the sky for over one week. Its daily flux measured with the Fermi Large Area Telescope at photon energies E > 100 MeV reached F100 = 22 ± 1 × 10-6 ph cm-2 s-1, representing the highest daily flux of any blazar ever recorded in high-energy -rays. It again became the brightest source in the sky in 2010 April, triggering a pointed-mode observation by Fermi. The correlated -ray temporal and spectral properties during these exceptional events are presented and discussed. The main results show flux variability over time scales less than 3 h and very mild spectral variability with an indication of gradual hardening preceding major flares. No consistent loop pattern emerged in the -ray spectral index vs flux plane. A minimum Doppler factor of ≈15 is derived, and the maximum energy of a photon from 3C 454.3 is ≈ 20 GeV. The spectral break at a few GeV is inconsistent with Klein-Nishina softening from power-law electrons scattering Lyα line radiation, and a break in the underlying electron spectrum in blazar leptonic models is implied.},
doi = {10.1088/0004-637X/721/2/1383},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 721,
place = {United States},
year = {2010},
month = {9}
}

Journal Article:
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Cited by: 88 works
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