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The Progenitor of Supernova 2004dj in a Star Cluster

Xiaofeng Wang·Yanbin Yang·Tianmeng Zhang·Jun Ma·Xu Zhou·Weidong Li·Yu-Qing Lou·Zongwei Li
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Abstract

The progenitor of type II-plateau supernova (SN) 2004dj is identified with a supergiant in a compact star cluster known as "Sandage Star 96" (S96) in the nearby spiral galaxy NGC 2403, which was fortuitously imaged as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey from Feb 1995 to Dec 2003 prior to SN 2004dj. The superior photometry of BATC images for S96, taken with 14 intermediate-band filters covering 3000-10000Å, unambiguously establishes the star cluster nature of S96 with an age of $\sim 20$Myr, a reddening of $\hbox{E}(B-V)\sim 0.35$ mag and a total mass of $\sim 96,000$M$_{\odot}$. The compact star cluster nature of S96 is also consistent with the lack of light variations in the past decade. The SN progenitor is estimated to have a main-sequence mass of $\sim$12M$_{\odot}$. The comparison of our intermediate-band data of S96 with the post-outburst photometry obtained as the SN has significantly dimmed, may hopefully conclusively establish the nature of the progenitor.

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Xiaofeng Wang, Yanbin Yang, Tianmeng Zhang, Jun Ma, Xu Zhou, Weidong Li, Yu-Qing Lou, Zongwei Li. 2005-05-14. The Progenitor of Supernova 2004dj in a Star Cluster. https://doi.org/10.1086/431903

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