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arXiv · 2007.13464

On the Energy Sources of the Most Luminous Supernova ASASSN-15lh

Long Li·Zi-Gao Dai·Shan-Qin Wang·Shu-Qing Zhong
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Abstract

In this paper, we investigate the energy-source models for the most luminous supernova ASASSN-15lh. We revisit the ejecta-circumstellar medium (CSM) interaction (CSI) model and the CSI plus magnetar spin-down with full gamma-ray/X-ray trapping which were adopted by \cite{Chatzopoulos16} and find that the two models cannot fit the bolometric LC of ASASSN-15lh. Therefore, we consider a CSI plus magnetar model with the gamma-rays/X-rays leakage effect to eliminate the late-time excess of the theoretical LC. We find that this revised model can reproduce the bolometric LC of ASASSN-15lh. Moreover, we construct a new hybrid model (i.e., the CSI plus fallback model), and find that it can also reproduce the bolometric LC of ASASSN-15lh. Assuming that the conversion efficiency ($\eta$) of fallback accretion to the outflow is typically $\sim10^{-3}$, we derive that the total mass accreted is $\sim3.9~M_\odot$. The inferred CSM mass in the two models is rather large, indicating that the progenitor could have experienced an eruption of hydrogen-poor materials followed by an energetic core-collapse explosion leaving behind a magnetar or a black hole.

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Long Li, Zi-Gao Dai, Shan-Qin Wang, Shu-Qing Zhong. 2020-07-27. On the Energy Sources of the Most Luminous Supernova ASASSN-15lh. https://arxiv.org/abs/2007.13464

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