The Energy Spectrum of TeV Gamma-Rays from the Crab Nebula
نویسندگان
چکیده
The imaging atmospheric Čerenkov technique has been successfully used for observations of the Crab Nebula in the TeV energy range. However the Crab Nebula energy spectra, measured by several groups, still differ noticeably in power-law index as well as in absolute -ray flux. The HEGRA stereoscopic system of 5 imaging atmospheric Čerenkov telescopes has been used for long-term observations of the Crab Nebula in 97/98 and 98/99, for a total of about 200 hrs at small ( 30 ) zenith angles and 50 hrs at large ( 60 ) zenith angles. The good energy resolution of 18%, the wide dynamic range from 500 GeV to 20 TeV, and the ability for systematic studies using several images for an individual shower, resulted in a very accurate measurement of the spectrum. We present the results of the analysis, using an advanced technique of energy spectrum evaluation, recently developed by the HEGRA group.
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