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arXiv · 2407.05968

Evidence for GeV emission of the superluminous supernova SN 2017egm

Shang Li·Yun-Feng Liang·Neng-Hui Liao·Lei Lei·Yi-Zhong Fan
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Abstract

Superluminous supernovae (SLSNe) are a new class of transients with luminosities $\sim10 -100$ times larger than the usual core-collapse supernovae (SNe). Their origin is still unclear and one widely discussed scenario involves a millisecond magnetar central engine. The GeV-TeV emission of SLSNe has been predicted in the literature but has not been convincingly detected yet. Here we report the results of the search for $\gamma$-ray emission in the direction of SN 2017egm, one of the closest SLSNe detected so far, using 15 years of {\it Fermi}-LAT Pass 8 data. There is a transient $\gamma$-ray source appearing about 2 months after this event and lasting a few months. Monte Carlo simulations show that the $\gamma$-ray signal has a global significance of {\it at least} 4$\sigma$. Both the peak time and the luminosity of the GeV emission are consistent with the magnetar model prediction, suggesting that such a GeV transient is the high-energy counterpart of SN 2017egm and the central engine of this SLSNe is a young magnetar.

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Shang Li, Yun-Feng Liang, Neng-Hui Liao, Lei Lei, Yi-Zhong Fan. 2024-07-08. Evidence for GeV emission of the superluminous supernova SN 2017egm. https://doi.org/10.1103/jhhk-ywtl

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