THE TeV GAMMA-RAY SPECTRUM OF MARKARIAN 421 DURING AN INTENSE FLARE
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چکیده
We present the gamma-ray spectrum of the BL Lacertae object, Markarian 421, above 500 GeV during its most intense recorded TeV flare, on 1996 May 7. The spectrum is well fitted by a power law with an exponent of (statistical and systematic errors). The spectrum extends above 5 TeV with no evidence 22.56 5 0.07 5 0.1 for a cutoff, favoring determinations of the extragalactic infrared energy density that do not produce a sharp cutoff at these energies. Subject headings: BL Lacertae objects: individual (Markarian 421) — gamma rays: observations
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تاریخ انتشار 1997