CANGAROO-III Observations of the 2006 Outburst of PKS2155-304

Abstract

We have used the CANGAROO-III imaging atmospheric Cherenkov telescopes to observe the high-frequency-peaked BL Lacertae (HBL) object PKS 2155-304 between 2006 July 28 (MJD 53944) and August 2, triggered by the H.E.S.S. report that the source was in a high state of TeV gamma-ray emission. A signal was detected at the 4.8 sigma level in an effective live time of 25.1 hours during the outburst period. The flux of Very High Energy gammarays from the CANGAROO-III observations shows the variability on the time scale of less than a few hours. The averaged integral flux above 660 GeV is (1.6 +/- 0.3_stat +/- 0.5_syst) x 10^-11 cm^-2 sec^-1 which corresponds to ~45% of the flux observed from the Crab nebula. Follow-up observations between August 17 (MJD 53964) and 25 indicate the source activity had decreased.

24 pages, 7 figures, to be published in ApJ

References in corpus (10)

• An Exceptional VHE Gamma-Ray Flare of PKS 2155-304
• Variable VHE gamma-ray emission from Markarian 501
• Observations of Mkn 421 with the MAGIC Telescope
• Long-Term X-Ray and TeV variability of Mrk 501
• X-ray/UV/Optical follow-up of the blazar PKS 2155-304 after the giant TeV flares of July 2006
• CANGAROO-III Observations of the supernova remnant RX J0852.0$-$4622
• A Simple Analytic Treatment of the Intergalactic Absorption Effect in Blazar Gamma-ray Spectra
• CANGAROO-III Search for Gamma Rays from Centaurus A and the $\omega$ Centauri Region
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Cited by in corpus (16)

• A ~4.6 h quasi-periodic oscillation in the BL Lacertae PKS 2155-304?
• The Parsec-Scale Jets of the TeV Blazars H 1426+428, 1ES 1959+650, and PKS 2155-304: 2001-2004
• Detection of Intra-day Variability Timescales of Four High Energy Peaked Blazars with XMM-Newton
• A multiwavelength view of the flaring state of PKS 2155-304 in 2006
• First-Epoch VLBA Imaging of Twenty New TeV Blazars
• XMM-Newton observations of the TeV BL Lac object PKS 2155--304 in 2006: signature of inverse Compton X-ray emission?
• Infrared to X-ray observations of PKS 2155-304 in a low state
• Spectral energy distributions of the BL Lac PKS 2155-304 from XMM-Newton
• Flux and spectral variability of the blazar PKS 2155-304 with XMM-Newton: Evidence of Particle Acceleration and Synchrotron Cooling
• High zenith angle observations of PKS 2155-304 with the MAGIC-I telescope
• HI in the Arp 202 system and its tidal dwarf candidate
• On the radio and NIR jet of PKS 2155-304 and its close environment
• Neutrinos from photo-hadronic interactions in Pks2155-304
• Recent Topics on Very High Energy Gamma-ray Astronomy
• CANGAROO-III Observation of TeV Gamma Rays from the vicinity of PSR B1 706-44
• Searches for very high energy gamma rays from blazars with CANGAROO-III telescope in 2005-2009