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arXiv · 2504.20407

Discovery of a variable yellow supergiant progenitor for the Type IIb SN 2024abfo

Zexi Niu·Ning-Chen Sun·Justyn R. Maund·Zhen Guo·Wenxiong Li·Meng Sun·Jifeng Liu
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Abstract

We report the discovery of a progenitor candidate for the Type~IIb SN2024abfo using multi-epoch pre-explosion images from the Hubble Space Telescope and the Dark Energy Camera Legacy Survey. The progenitor exhibited a ~0.7 mag decline in F814W from 2001 to 2013, followed by significant brightening and color fluctuations in the g, r and z bands. This is the first time that substantial photometric variability has been found for the progenitor of a SN IIb. We suggest that the variability is caused by intrinsic changes in the progenitor star instead of varying obscuration by circumstellar dust. Our results show that the progenitor of SN2024abfo was likely a yellow supergiant star with an initial mass of 12--18 Msun for circumstellar reddening of E(B-V)_CSM < 0.2 mag. Our study underscores the critical role of multi-epoch imaging surveys in revealing the final stages of core-collapse supernovae progenitors.

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Zexi Niu, Ning-Chen Sun, Justyn R. Maund, Zhen Guo, Wenxiong Li, Meng Sun, Jifeng Liu. 2025-04-29. Discovery of a variable yellow supergiant progenitor for the Type IIb SN 2024abfo. https://arxiv.org/abs/2504.20407

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