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Title: Spectral energy distribution of Markarian 501: Quiescent state versus extreme outburst

Journal Article · · The Astrophysical Journal
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Here, the very high energy (VHE; E > 100 GeV) blazar Markarian 501 (Mrk 501) has a well-studied history of extreme spectral variability and is an excellent laboratory for studying the physical processes within the jets of active galactic nuclei. However, there are few detailed multiwavelength studies of Mrk 501 during its quiescent state, due to its low luminosity. A short-term multiwavelength study of Mrk 501 was coordinated in 2009 March, focusing around a multi-day observation with the Suzaku X-ray satellite and including γ-ray data from VERITAS, MAGIC, and the Fermi Gamma-ray Space Telescope with the goal of providing a well-sampled multiwavelength baseline measurement of Mrk 501 in the quiescent state. The results of these quiescent-state observations are compared to the historically extreme outburst of 1997 April 16, with the goal of examining variability of the spectral energy distribution (SED) between the two states. The derived broadband SED shows the characteristic double-peaked profile. We find that the X-ray peak shifts by over two orders of magnitude in photon energy between the two flux states while the VHE peak varies little. The limited shift in the VHE peak can be explained by the transition to the Klein-Nishina (KN) regime. Synchrotron self-Compton models are matched to the data and the implied KN effects are explored.

Research Organization:
SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Organization:
USDOE
Contributing Organization:
The VERITAS Collaboration; The MAGIC Collaboration
Grant/Contract Number:
AC02-76SF00515
OSTI ID:
1357263
Journal Information:
The Astrophysical Journal, Vol. 729, Issue 1; ISSN 0004-637X
Publisher:
Institute of Physics (IOP)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 58 works
Citation information provided by
Web of Science

References (35)

FERMI LARGE AREA TELESCOPE FIRST SOURCE CATALOG journal May 2010
INSIGHTS INTO THE HIGH-ENERGY γ-RAY EMISSION OF MARKARIAN 501 FROM EXTENSIVE MULTIFREQUENCY OBSERVATIONS IN THE FERMI ERA journal January 2011
VERITAS Observations of the γ‐Ray Binary LS I +61 303 journal June 2008
TeV gamma rays from BL Lac objects due to synchrotron radiation of extremely high energy protons journal November 2000
Reanalysis of the high energy cutoff of the 1997 Mkn 501 TeV energy spectrum journal January 2001
Variable Very High Energy γ‐Ray Emission from Markarian 501 journal November 2007
Unfolding of differential energy spectra in the MAGIC experiment
  • Albert, J.; Aliu, E.; Anderhub, H.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 583, Issue 2-3 https://doi.org/10.1016/j.nima.2007.09.048
journal December 2007
VHE γ‐Ray Observation of the Crab Nebula and its Pulsar with the MAGIC Telescope journal February 2008
Implementation of the Random Forest method for the Imaging Atmospheric Cherenkov Telescope MAGIC
  • Albert, J.; Aliu, E.; Anderhub, H.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 588, Issue 3 https://doi.org/10.1016/j.nima.2007.11.068
journal April 2008
Improving the performance of the single-dish Cherenkov telescope MAGIC through the use of signal timing journal January 2009
SIMULTANEOUS MULTIWAVELENGTH OBSERVATION OF Mkn 501 IN A LOW STATE IN 2006 journal October 2009
THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION journal May 2009
Background modelling in very-high-energy γ -ray astronomy journal April 2007
The Cosmic X-ray Background book January 1987
Multiwavelength Observations of a Flare from Markarian 501 journal October 1997
First results on the performance of the HEGRA IACT array journal December 1997
New methods of atmospheric Cherenkov imaging for gamma-ray astronomy. I. The false source method journal May 1994
Extragalactic optical-infrared background radiation, its time evolution and the cosmic photon-photon opacity journal June 2008
Status of the VERITAS Observatory
  • Holder, J.; Acciari, V. A.; Aliu, E.
  • HIGH ENERGY GAMMA-RAY ASTRONOMY: Proceedings of the 4th International Meeting on High Energy Gamma-Ray Astronomy, AIP Conference Proceedings https://doi.org/10.1063/1.3076760
conference January 2008
X-Ray Imaging Spectrometer (XIS) on Board Suzaku journal January 2007
Multiwavelength Observations of Strong Flares from the TeV Blazar 1ES 1959+650 journal January 2004
Analysis methods for results in gamma-ray astronomy journal September 1983
A jet model for the gamma-ray emitting blazar 3C 279 journal September 1992
Models for high-frequency radio outbursts in extragalactic sources, with application to the early 1983 millimeter-to-infrared flare of 3C 273 journal November 1985
The Likelihood Analysis of EGRET Data journal April 1996
Multiwavelength Observations of Markarian 501 during the 1997 High State journal June 2000
[ITAL]BeppoSAX[/ITAL] Observations of Unprecedented Synchrotron Activity in the BL Lacertae Object Markarian 501 journal January 1998
Detection of Gamma Rays with [ITAL]E[/ITAL] ] 300 GeV from Markarian 501 journal January 1996
Correlated Intense X‐Ray and TeV Activity of Markarian 501 in 1998 June journal July 2000
Comptonization of diffuse ambient radiation by a relativistic jet: The source of gamma rays from blazars? journal January 1994
The Bell Laboratories H I survey journal March 1992
Hard X-Ray Detector (HXD) on Board Suzaku journal January 2007
Constraints on the Physical Parameters of TeV Blazars journal December 1998
Unified Schemes for Radio-Loud Active Galactic Nuclei journal June 1995
X‐Ray Flares from Markarian 501 journal March 2005

Cited By (23)

Multiwavelength observations of Mrk 501 in 2008 journal December 2014
On the detectability of Lorentz invariance violation through anomalies in the multi-TeV γ -ray spectra of blazars journal December 2015
Very high energy outburst of Markarian 501 in May 2009 journal October 2016
Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009 journal July 2017
Long-term optical monitoring of TeV emitting blazars: I. Data analysis⋆ journal December 2018
Extreme HBL behavior of Markarian 501 during 2012 journal December 2018
The elm Survey. v. Merging Massive White Dwarf Binaries journal May 2013
Axion-like particle imprint in cosmological very-high-energy sources journal November 2011
The origin of multi-TeV flares from the nearest blazar Markarian 421 journal July 2018
Main physics results of the ARGO-YBJ experiment journal August 2014
VERITAS and multiwavelength observations of the BL Lacertae object 1ES 1741+196 text January 2016
Multi-Color Optical Monitoring of mrk 501 from 2010 to 2015 journal February 2016
Stable Radio Core of the Blazar Mrk 501 during High-energy Active State in 2012 journal October 2019
Multi-wavelength Variability Signatures of Relativistic Shocks in Blazar Jets journal December 2019
The ELM Survey. VIII. Ninety-eight Double White Dwarf Binaries journal January 2020
VERITAS and multiwavelength observations of the BL Lacertae object 1ES 1741+196 journal April 2016
Very high energy outburst of Markarian 501 in May 2009 text January 2016
Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009 text January 2017
The extreme HBL behaviour of Markarian 501 during 2012 text January 2018
Axion-like particle imprint in cosmological very-high-energy sources text January 2011
The ELM Survey. V. Merging Massive White Dwarf Binaries text January 2013
Multi-color optical monitoring of Mrk 501 from 2010 to 2015 text January 2015
Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009 text January 2016

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