AI 中文总结
该研究探讨仪器设置对强引力透镜II型超新星时延测量及H₀精度的影响，结合多吸收线时延测量可实现低时延不确定度，未来有望通过约20个此类超新星将H₀精度提升至1%。
AI 中文摘要
即将开展的Rubin望远镜观测及后续跟进观测，有望通过强引力透镜II型超新星（LSNe II）的时延宇宙学方法，提升哈勃常数（H₀）的测量精度，因为这类观测可探测到更多此类事件。在我们此前的研究中，已开发出一种利用光谱吸收特征确定超新星（SN）相位的方法。由于获取遥远II型超新星这类暗弱目标的光谱成本高昂，我们研究了低分辨率光谱对时延反演精度的影响，进而对H₀测量精度的影响。我们考虑的光谱分辨率R=λ/Δλ范围为100至250，且针对每种分辨率，分别研究了信噪比（S/N）为10、15、20三种情况。此外，我们预测了S/N=10时H₀的可实现精度，并对比了地基和天基设备达到该精度所需的观测时间。研究发现，当结合多条吸收线的时延测量时，在研究的分辨率和信噪比范围内，时延可无偏差确定，不确定性低至1.3天。对于典型的LSNe II系统（静止帧V波段绝对星等约为-17等，源红移zₛ=0.8），所需曝光时间从地基观测的数小时到JWST天基观测的数分钟不等。我们对单个引力透镜超新星的H₀精度预测，在R=100且S/N=10时为14.2%，在R=250且S/N=20时为7.5%，这意味着未来几年内，通过约20个引力透镜超新星可实现H₀的1%精度测量。
英文摘要
The upcoming Rubin Observatory and subsequent follow-up observations should improve the determination of the Hubble constant ($H_0$) via time-delay cosmography of strongly lensed type II supernovae (LSNe II), by enabling the detection of many more such events. In our previous work, we developed a method for determining the supernova (SN) phase from spectral absorption features. Because obtaining spectra of faint targets such as distant SN II is expensive, we examined how low-resolution spectra influence the precision of time-delay retrieval, and consequently the precision on $H_0$. We considered spectral resolutions $R = \fracλ{Δλ}$ between 100 and 250, and we investigated three signal-to-noise ratio ($S/N$) values of 10, 15, and 20, for each resolution. Furthermore, we forecast the precision on $H_{0}$ achievable with $S/N=10$ and compared the observing time required to reach it with ground-based and space-based facilities. We find that the time delay can be determined without bias and with uncertainties as low as 1.3 days for the investigated resolutions and $S/N$ values when we combine time-delay measurements of multiple absorption lines. For a typical LSN II system (absolute magnitude $\sim-$17 mag in the rest-frame V band, source redshift of \zs = 0.8), the required exposure times range from multiple hours for ground-based observations to a few minutes for space-based observations with the JWST. Our predictions on the precision of $H_0$ for a single lensed SN range from 14.2\% for $R = 100$ and $S/N$ = 10 to 7.5\% for $R = 250$ and $S/N$ = 20, enabling a 1\% determination of $H_0$ from $\sim$20 lensed SNe in the coming years.
Comments17 pages, 12 figures, 10 tables
Journal refA&A 710, A258 (2026)
DOI：10.1051/0004-6361/202555795
