标题： 博格-$JWST$调查：在$z\sim8$的类比以及在$z\gtrsim10$的紫外线发光星系群体 显示英文标题

标题： The BoRG-$JWST$ Survey: Analogs at $z\sim8$ to the UV-luminous Galaxy Population at $z\gtrsim10$

摘要： 在$z\gtrsim10$处由JWST发现的明亮星系，包括所谓的“蓝色怪物”，很难与标准星系演化模型相协调。 为了揭示这一特殊群体，我们研究了BoRG-$JWST$调查中发现的$z\sim8$星系。 这些稍低红移的类似物在紫外光度上与蓝色怪物相当，它们的较低红移使得使用NIRspec更容易获取关键的静止框架光学诊断信息。 我们发现，基于其蓝色的紫外斜率和巴尔末减幅比，BoRG-$JWST$星系似乎缺乏尘埃。 我们没有发现强有力的证据表明活动星系核对紫外亮度有主要贡献，尽管不能排除一些贡献。 我们进一步通过拟合BoRG-$JWST$星系的静止框架紫外-光学光谱，推断出它们的恒星质量、恒星形成和紫外亮度历史。 我们看到所有BoRG-$JWST$星系都存在随机的恒星形成事件，这在短时间内提升了紫外光度。 在$z\gtrsim10$处的紫外明亮的蓝色怪物可以通过年龄低于1亿年的恒星来解释。 显示英文摘要

摘要： The population of bright galaxies at $z\gtrsim10$ discovered by JWST, including the so-called "blue monsters", has been difficult to reconcile with standard galaxy evolution models. To shed light on this extraordinary population, we study the $z\sim8$ galaxies discovered by the BoRG-$JWST$ survey. These slightly-lower redshift analogs are comparable in UV luminosity to the blue monsters, and their lower redshift makes it much easier to access key rest frame optical diagnostics with NIRspec. We find that BoRG-$JWST$ galaxies are consistent with being dust-poor based on their blue UV slopes and Balmer decrement ratios. We find no strong evidence for dominant active galactic nuclei contribution to the UV brightness, based on line-ratio diagnostics, though some contribution cannot be excluded. We further infer the stellar mass, star formation and UV-brightness history of the BoRG-$JWST$ galaxies by fitting their rest-frame UV-optical spectra. We see evidence for stochastic episodes of star formation for all the BoRG-$JWST$ galaxies, providing a temporal boosting of UV luminosity in short timescales. The UV-bright blue monsters at $z\gtrsim10$ can be explained by the presence of stars with ages below 100 Myr.