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تسجيل مستخدم جديدSearch for TeV $gamma$ -rays from H1426+428 during 2004-07 with the TACTIC telescope
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The BL Lac object H1426+428 ($zequiv 0.129$) is an established source of TeV $gamma$-rays and detections of these photons from this object also have important implications for estimating the Extragalactic Background Light (EBL) in addition to the understanding of the particle acceleration and $gamma$-ray production mechanisms in the AGN jets. We have observed this source for about 244h in 2004, 2006 and 2007 with the TACTIC $gamma$-ray telescope located at Mt. Abu, India. Detailed analysis of these data do not indicate the presence of any statistically significant TeV $gamma$-ray signal from the source direction. Accordingly, we have placed an upper limit of $leq1.18times10^{-12}$ $photons$ $cm^{-2}$ $s^{-1}$ on the integrated $gamma$-ray flux at 3$sigma$ significance level.
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