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تسجيل مستخدم جديدMeasurement of the flux, spectrum, and variability of TeV gamma-rays from Mkn 501 during a state of high activity
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Between March 16, 1997 and April 14, 1997, a high flux level of TeV gamma-rays was observed from Mkn 501, using the HEGRA stereoscopic system of four imaging Cherenkov telescopes. The flux level varied during this period from about one half up to six times the flux observed from the Crab Nebula. Changes of the detection rate by a factor of up to 4 within 1 day have been observed. The measured differential energy spectrum of the radiation follows a power law from 1 TeV to 10 TeV. The differential spectral index of 2.47{+-}0.07{+-}0.25 is close to that of the Crab Nebula of 2.66{+-}0.12{+-}0.25.
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Markarian 501 is only the second extragalactic source to be detected with high statistical certainty at TeV energies; it is similar in many ways to Markarian 421. The Whipple Observatory gamma-ray telescope has been used to observe the AGN Markarian
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We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA, EGRET, Whipple, and optical telescopes. In the X-ray band, a spectral break was observed around 2 keV. We report here for the first time the detection
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