AI 中文总结
该研究通过探测高红移古老星团确定年龄-红移关系，以宇宙宝石弧为例，经图像反卷积、SED拟合等得出恒星年龄，联合贝叶斯拟合测量宇宙学参数，虽当前约束宽松，但预测未来样本可提高精度，为宇宙学研究开辟新途径。
AI 中文摘要
在这项工作中，我们通过探测高红移最古老的星团来探索跨越宇宙时间确定年龄-红移关系的潜力，这些星团因詹姆斯·韦布空间望远镜在强引力透镜场中得以观测。以观测到的最高红移系统之一、红移为\(z = 9.625\)的宇宙宝石弧为例，对多波段JWST成像进行图像反卷积，沿弧识别出总共20个点源。通过与宇宙学无关的光谱能量分布（SED）拟合框架得出恒星年龄。结合这些高红移系统和本地球状星团年龄，在平坦的\(\Lambda\)CDM模型中对年龄-红移关系进行联合贝叶斯拟合，测量出\(H_0 = 70^{+27}_{-16}\ \rm{km\ s^{-1}\ Mpc^{-1}}\)和\(\Omega_m = 0.33^{+0.37}_{-0.21}\)。虽这些约束仍宽松，但简并斜率在\(\Omega_m - H_0\)平面呈幂律且高度依赖源的红移，红移增加时变浅。利用此几何旋转进行预测，未来约300个分布在\(z \approx 10\)以下的透镜化原球状星团样本可将\(H_0\)统计精度提高到\(4\%\)，\(\Omega_m\)提高到\(11\%\)，与现有方法竞争且独立。当前工作代表了宇宙学新途径，恰逢JWST常规观测高红移透镜化星团、欧几里得和南希·格雷斯·罗曼太空望远镜发现新强引力透镜场以及ESO极大望远镜即将投入使用之际。
英文摘要
In this work, we explore the potential of anchoring the age-redshift relation across cosmic time by probing the oldest star clusters at high redshift, now observed thanks to the James Webb Space Telescope in strongly lensed fields. As a case study, we consider one of the highest-redshift systems observed, the Cosmic Gems arc at $z=9.625$. We perform image deconvolution of multi-band JWST imaging, identifying a total of 20 point sources along the arc. We derive the stellar ages through a cosmology-independent spectral energy distribution (SED) fitting framework, ensuring that these measurements can be used as unbiased cosmological anchors. By combining these high-z systems with state-of-the-art local globular cluster ages, we perform a joint Bayesian fit to the age-redshift relation in a flat $Λ$CDM model, measuring $H_0=70^{+27}_{-16}\ \rm{km\ s^{-1}\ Mpc^{-1}}$ and $Ω_m=0.33^{+0.37}_{-0.21}$. While these constraints are still loose, we show that the slope of the degeneracy, a power-law in the $Ω_m - H_0$ plane, is highly dependent on the redshift of the sources, becoming shallower as redshift increases. Leveraging this geometric rotation, we present forecasts showing that a future sample of $\sim 300$ lensed proto-globular clusters well-distributed up to $z \approx 10$ could tighten the statistical precision to $4\%$ on $H_0$ and $11\%$ on $Ω_m$, competitive with and independent of methods currently in use. The present work, therefore, represents a new avenue in cosmology and comes at a timely moment, when JWST observes high-redshift lensed star clusters routinely, Euclid and the Nancy Grace Roman Space Telescope uncover new strong lensing fields, and close to the start of operation of the ESO Extremely Large Telescope.
Comments12 pages, 8 figures, 1 table. Submitted to A&A
