AI 中文总结
研究了红移\(z = 5.13\)的超新星厄俄斯及其宿主星系，利用引力透镜多重成像和高放大倍数解析系统，确定超新星位置并描述其环境，发现宿主超暗且贫金属，为星系化学富集及高红移贫金属环境超新星率研究提供线索。
AI 中文摘要
我们首次对最近发现的红移\(z = 5.13\)的 IIP 型超新星（超新星厄俄斯）的宿主星系进行了特征描述。超新星厄俄斯及其宿主星系受到引力透镜作用且有多重成像。总放大倍数\(\mu\sim53\)使我们能够在空间上分辨该系统，从而确定核心坍缩超新星（CCSN）的位置并描述其在早期星系中的局部环境。我们的观测表明，宿主是一个超暗（\(M_{\rm UV}=-14.4\pm0.3\)星等）的莱曼\(\alpha\)发射体，等效宽度非常高。尽管检测到了 H\(\alpha\)线（在 B 型复合情况下，[O iii]5007/H\(\beta <0.7\)），但宿主星系的[O iii]4959、5007 线非常弱。假设鉴于超新星厄俄斯本身的低金属性，弱[O iii]是由于气相金属性低，那么超新星厄俄斯可能标志着一颗贫金属恒星在极其贫金属的环境（\(<1\ \%\ Z_\odot\)）中的形成和爆炸，促进了宿主星系化学富集的初始阶段。在这样一个红移\(z = 5.13\)的超暗星系中发现核心坍缩超新星也表明，在高红移、贫金属环境中超新星率可能会显著更高，这可能意味着例如与金属丰度\(Z\)相关的初始质量函数、与\(Z\)相关的大质量恒星可爆性或致密星团中的失控恒星碰撞。如果没有透镜作用，在以往任何 NIRCam 调查中，只有超新星厄俄斯可被检测到，而宿主将低于检测极限。因此，厄俄斯宿主星系可以代表在 JWST 空白场调查中经常发现的无宿主超新星的起源。
英文摘要
We present the first characterization of the host galaxy of a recently discovered type IIP SN at $z=5.13$ (SN Eos). SN Eos and its host galaxy are gravitationally lensed and multiply imaged. The total magnification $μ\sim53$ enables spatially resolving the system, allowing us to localize the core-collapse supernova (CCSN) position and to characterize its local environment within an early galaxy. Our observation reveals that the host is an ultra-faint ($M_{\rm UV}=-14.4\pm0.3$ mag) Lyman-$α$ emitter with a very high equivalent width. The host galaxy also shows very weak [O iii]4959,5007 lines despite an H$α$ line detection ([O iii]5007/H$β<0.7$ with case B recombination). Assuming that the weak [O iii] is due to low gas-phase metallicity given the low-metallicity of SN Eos itself, SN Eos plausibly marks the formation and explosion of a metal-poor star in an extremely metal-poor environment ($<1\ \%\ Z_\odot$), facilitating the initial stages of the chemical enrichment of the host. Finding the CCSN in such an ultra-faint galaxy at $z=5.13$ also indicates that the SN rate could be considerably higher in high-$z$, metal-poor environments, potentially implying e.g., a $Z$-dependent IMF, $Z$-dependent massive star explodability, or runaway stellar collisions in dense star clusters. Without lensing, only SN Eos would be detectable and the host would be below the detection limit in any NIRCam surveys ever performed. The Eos host galaxy can thus be representative of the origin of {\it hostless} supernovae frequently found in JWST blank field surveys.
CommentsSubmitted to ApJ. Comments are welcome!
