标题： 2024abfo型IIb超新星的低质量双星剥离包层 显示英文标题

标题： A low mass, binary-stripped envelope for the Type IIb SN 2024abfo

摘要： IIb型超新星（SNe）是剥离包层SNe的一个过渡亚类，其光谱中显示出氢线，这些线逐渐减弱并被类似于Ib型超新星的氦线取代，这表明通过恒星风或双星相互作用进行了剥离。 SN 2024abfo是第七个有直接前身星检测的IIb型超新星。 我们发现超新星在我们的ERIS自适应光学成像中的位置与档案HST成像中的前身星位置一致，误差在19毫角秒以内。 前身星的SED与A5巨星一致。 单星模型预测初始质量在11到15个太阳质量之间，而最可能的双星模型是一个12+1.2个太阳质量的系统，初始周期为1.73年。 我们还发现，在核心坍缩前的几年里，前身星候选体有显著的变化证据。 SN 2024abfo是具有直接前身星检测的最暗淡的IIb型超新星。 在后期，r波段光曲线衰减比比较SNe更慢，这可能是由于伽马射线捕获增加所致。 类似于SN 2008ax，SN 2024abfo没有明显的双峰光曲线。 我们的半解析光曲线建模表明，这可能是由于外层包层中的氢质量非常低。 光谱上，SN 2024abfo在早期时间最类似于SN 2008ax，而在后期时间（80天）相比比较样本，似乎表现出持续的Halpha吸收。 我们更倾向于用双星系统来解释超新星及其前身星，尽管我们无法排除单星模型。 我们建议进行晚期观测以寻找双星伴星和CSM相互作用的迹象。 缺乏这些特征将支持SN 2024abfo源自一个在爆炸前（1000年）经历了双星质量转移时期的系统，导致了一个低质量的富氢包层。 显示英文摘要

摘要： Type IIb supernovae (SNe) are a transitional subclass of stripped-envelope SNe showing hydrogen lines in their spectra that gradually weaken and give way to helium lines reminiscent of SNe Ib, which is indicative of stripping through stellar winds or binary interaction. SN 2024abfo is the seventh SN IIb with a direct progenitor detection. We find that the position of the supernova in our ERIS adaptive optics imaging agrees with the progenitor position in archival HST imaging to within 19 mas. The progenitor SED is consistent with an A5 giant. Single star models predict an initial mass in the range 11 to 15 solar masses, while the most probable binary model is a 12+1.2 solar mass system with an initial period of 1.73 years. We also find significant evidence for variability of the progenitor candidate in the years prior to core-collapse. SN 2024abfo is the least luminous SN IIb with a direct progenitor detections. At late times the r-band light curve decays more slowly than the comparison SNe, which may be due to increased gamma-ray trapping. Similar to SN 2008ax, SN 2024abfo does not show a prominent double-peaked light curve. Our semi-analytic light curve modelling shows that this may be due to a very low mass of hydrogen in the outer envelope. Spectrally, SN 2024abfo is most similar to SN 2008ax at early times while at later times (80 days) it appears to show persistent Halpha absorption compared to the comparison sample. We prefer a binary system to explain the supernova and its progenitor, although we are unable to rule out single-star models. We recommend late-time observations to search for a binary companion and signatures of CSM-interaction. The absence of these features would support the hypothesis that SN 2024abfo resulted from a system which underwent a period of binary mass transfer well before (1000 yr) the explosion, resulting in a low-mass hydrogen-rich envelope.