An Exceptional Very High Energy Gamma-Ray Flare of PKS 2155-304

@article{Aharonian2007AnEV,
  title={An Exceptional Very High Energy Gamma-Ray Flare of PKS 2155-304},
  author={Felix Aharonian and et al.},
  journal={The Astrophysical Journal},
  year={2007},
  volume={664}
}
The high-frequency peaked BL Lac PKS 2155-304 at redshift z = 0.116 is a well-known VHE (>100 GeV) γ-ray emitter. Since 2002 its VHE flux has been monitored using the H.E.S.S. stereoscopic array of imaging atmospheric Cerenkov telescopes in Namibia. During the 2006 July dark period, the average VHE flux was measured to be more than 10 times typical values observed from the object. This article focuses solely on an extreme γ-ray outburst detected in the early hours of 2006 July 28 (MJD 53,944… 
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References

SHOWING 1-10 OF 24 REFERENCES
H.E.S.S. Observations of PKS 2155-304
TLDR
The suggested presence of features in the energy spectrum may be intrinsic to the emission from the blazar, or an indication of absorption of TeV gamma rays by the extragalactic infrared background light.
Variable Very High Energy γ-Ray Emission from Markarian 501
The blazar Markarian 501 (Mrk 501) was observed at energies above 0.10 TeV with the MAGIC telescope from May through July 2005. The high sensitivity of the instrument enabled the determination of the…
Multi-wavelength observations of PKS 2155-304 with HESS
TLDR
The energy outputs in the 2–10 keV and in the VHE γ-ray range are found to be similar, with the X-rays and the optical fluxes at a level comparable to some of the lowest historical measurements, indicating that PKS 2155−304 was in a low or quiescent state during the observations.
A Rapid X-ray Flare from Markarian 501.
TLDR
X-ray observations of the BL Lacertae object Mrk 501 that were taken with the Rossi X-Ray Timing Explorer in 1998 May as part of a multiwavelength campaign show a very rapid flare in which the 2-10 keV flux increased by approximately 60% in less than 200 s and the shift in the energy at which the spectral power peaks is among the most rapid shifts seen from this object.
Rapid X-Ray Variability of the BL Lacertae Object PKS 2155–304
We present a detailed power-density spectrum and cross-correlation analysis of the X-ray light curves of the BL Lac object PKS 2155-304, observed with BeppoSAX in 1997 (SAX97) and 1996 (SAX96), aimed…
X-Ray Flares from Markarian 501
Motivated by the recent discovery of a hierarchical X-ray flaring phenomenon in Mrk 421, we conducted a systematic search for X-ray flares from Mrk 501, another well-known TeV blazar, by making use…
Extremely rapid bursts of TeV photons from the active galaxy Markarian 421
DISCRETE astronomical sources of photons in the TeV energy range are believed to be associated with regions in the relativistic outflow of particles and radiation from compact objects, such as…
A study of BL lacertae-type objects with EXOSAT. I, Flux correlations, luminosity variability, and spectral variability
Results are presented on a systematic analysis of more than 200 X-ray observations on 36 BL Lac objects, obtained from the Exosat archive, providing further strong evidence that the population of…
XMM-NEWTON VIEW OF PKS 2155-304: CHARACTERIZING THE X-RAY VARIABILITY PROPERTIES WITH EPIC pn
Starting from XMM-Newton EPIC pn data, we present the X-ray variability characteristics of PKS 2155-304 using a simple analysis of the excess variance, sigma(2)(XS), and of the fractional rms…
Background modelling in very-high-energy gamma-ray astronomy
Ground based Cherenkov telescope systems measure astrophysical {gamma}-ray emission against a background of cosmic-ray induced air showers. The subtraction of this background is a major challenge for…
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