STACEE Observations of Mrk 421 During the 2001 Flare
نویسندگان
چکیده
STACEE is a ground based γ-ray observatory that uses a heliostat array, built for solar energy research, to detect atmospheric Cherenkov radiation from γ-ray initiated extensive air showers. During the first half of 2001, a prototype detector, STACEE-48, was used to detect the blazar Markarian 421, which was in an extremely active state. Observations from March to May of 2001 yielded an integral flux of (8.0± 0.7stat ± 1.5sys)× 10−10cm−2s−1 at energies above 140± 20 GeV, and provide some evidence of correlated trends on time scales of a week or more in the GeV and X-ray bands.
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