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تسجيل مستخدم جديدBVRI Photometry of the Classic Type II-P Supernova 2017eaw in NGC 6946: Day 3 to Day 594
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Broadband $BVRI$ light curves of SN 2017eaw in NGC 6946 reveal the classic elements of a Type II-P supernova. The observations were begun on 16 May 2017 (UT), approximately 1 day after the discovery was announced, and the photometric monitoring was carried out over a period of nearly 600 days. The light curves show a well-defined plateau and an exponential tail which curves slightly at later times. An approximation to the bolometric light curve is derived and used to estimate the amount of $^{56}$Ni created in the explosion; from various approaches described in the literature, we obtain $M$($^{56}{rm Ni}$) = 0.115 ($-$0.022,+0.027)$M_{odot}$. We also estimate that 43% of the bolometric flux emitted during the plateau phase is actually produced by the $^{56}$Ni chain. Other derived parameters support the idea that the progenitor was a red supergiant.
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We present extensive optical photometric and spectroscopic observations, from 4 to 482 days after explosion, of the Type II-plateau (II-P) supernova (SN) 2017eaw in NGC 6946. SN 2017eaw is a normal SN II-P intermediate in properties between, for exam
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