AI 中文总结
研究通过分析两个引力透镜系统中的星团种群，利用新测光和贝叶斯分析，发现GEMS星团在 \(z\sim 10\) 形成，金属丰度低，火花星系星团在 \(z\sim 2 - 3.5\) 形成，金属丰度较高，共同探测了不同时期星团形成环境。
AI 中文摘要
球状星团（GCs）的起源与其宿主星系的组装有关。我们分析了两个强烈引力透镜系统中的星团种群，这两个系统跨越宇宙黎明和宇宙正午：红移 \(z = 9.625\) 的宇宙宝石弧（GEMS），属于最早的星系之一，以及红移 \(z = 1.378\) 的火花星系。对GEMS进行的新的STARRED反卷积测光为十个独特的、双重成像的星团候选体提供了光谱能量分布，同时均匀贝叶斯分析将这两个种群置于共同的宇宙学时间线上。GEMS星团在 \(z_{\rm form}\approx 10\) - \(11\)（中位数 \(\simeq10.2\)）形成，与原子冷却尺度或以上的晕组装一致。它们的测光需要低金属丰度：单个星团与 \([Z/{\rm H}] \lesssim -1.2\) 一致，数据排除了 \([Z/{\rm H}]\geq -0.5\)，尽管在 \([Z/{\rm H}] \simeq -1.5\) 以下无法可靠区分。当使用包括双星演化的恒星种群模型时，这一结论不变，该模型对这个年龄的紫外线发射很重要，产生了同样低的金属丰度，\([Z/{\rm H}] = -2.2\) 到 \(-2.7\)。形式估计 \([Z/{\rm H}] = -2.3\pm0.3\) 与银河系GC金属丰度下限一致，但其值仍然依赖于先验。火花星系星团在宇宙正午的一个矮星系中，约在 \(z_{\rm form}\approx 2\) - \(3.5\) 时形成，比GEMS星团晚约25亿年，且金属丰度更高（\([Z/{\rm H}] \approx -0.5\)）。与银河系GCs的比较表明，GEMS处于异常早期、贫金属状态，火花星系处于后期、金属丰度更高的种群中，尽管两者都不能唯一确定其原位或异位起源。封闭箱和气体调节器计算表明，这两个系统都与有限的预富集、随后的快速富集和吸积调节生长兼容。它们共同探测了从宇宙黎明到宇宙正午不同的星团形成环境。
英文摘要
Origins of globular clusters (GCs) are linked to the assembly of their host galaxies. We analyze star-cluster populations in two strongly lensed systems that bracket Cosmic Dawn and Cosmic Noon: the Cosmic Gems arc (GEMS) at z=9.625, among the first galaxies, and the Sparkler at z=1.378. New STARRED deconvolution photometry of GEMS provides SEDs for ten unique, doubly imaged cluster candidates, while a homogeneous Bayesian analysis places both populations on a common cosmological timeline. The GEMS clusters formed at $z_{\rm form}\approx 10$--$11$ (median $\simeq10.2$), consistent with halo assembly at or above the atomic-cooling scale. Their photometry requires low metallicities: individual clusters are consistent with $[Z/{\rm H}] \lesssim -1.2$, and the data exclude $[Z/{\rm H}]\geq-0.5$, though they cannot distinguish reliably below $[Z/{\rm H}] \simeq -1.5$. This conclusion is unchanged when using stellar-population models including binary evolution---important for ultraviolet emission at this age---yielding similarly low metallicities, $[Z/{\rm H}]=-2.2$ to $-2.7$. The formal estimate, $[Z/{\rm H}] = -2.3\pm0.3$, is consistent with the Milky Way GC metallicity floor, though its value remains prior-dependent. The Sparkler clusters formed $\sim2.5$ Gyr later, at $z_{\rm form}\approx 2$--$3.5$ in a Cosmic Noon dwarf galaxy, and are more enriched ($[Z/{\rm H}] \approx -0.5$). Comparison with Milky Way GCs places GEMS in an exceptionally early, metal-poor regime and the Sparkler among later, more enriched populations, though neither association uniquely determines an in-situ or ex-situ origin. Closed-box and gas-regulator calculations show both systems are compatible with limited pre-enrichment followed by rapid enrichment and accretion-regulated growth. Together, they probe distinct cluster-forming environments from Cosmic Dawn to Cosmic Noon.
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