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arXiv · 0712.3094

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

III collaboration·Y. Sakamoto·K. Nishijima·T. Mizukami·E. Yamazaki·J. Kushida
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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.

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III collaboration, Y. Sakamoto, K. Nishijima, T. Mizukami, E. Yamazaki, J. Kushida. 2007-12-19. CANGAROO-III Observations of the 2006 Outburst of PKS2155-304. https://doi.org/10.1086/528369

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