论文标题
在回归时代的强烈[O III]发射器的推断恒星形成历史中解决歧义
Resolving Ambiguities in the Inferred Star Formation Histories of Intense [O III] Emitters in the Reionisation Era
论文作者
论文摘要
早期的JWST光谱运动已经证实了在红移间隔$ 7 <z <9 $中存在强烈的[O III]发射星系。尽管从尖峰光度法中推断为年轻恒星种群的指示，但一些研究表明，归因于[O III]发射的相关光度过量可能部分是由于较老的恒星引起的Balmer断裂。我们证明，在哈勃超深场中利用中型近红外JWST光度法可能是这种情况。我们找到了6个带有红移的星系的样本8.2 $ <z <z <$ 8.6，相关中等波段过滤器使我们能够将[O III]排放和Balmer断裂的贡献分开，从而破坏了早期的解释变性。该技术特别有价值，因为它提供了光度红移，其精度为$δ\，z \ simeq \，\ pm0.08 $，现在正在与JWST进行光谱活动。尽管有些消息来源很年轻，但我们三分之一的样本具有突出的Balmer断裂，与$ \ geq $ 150 Myr一致。我们的结果表明，即使是激烈的[O III]发射器也经历了早期星形形成的发作，$ z \ sim $ 10及以后，现在可以独立地推断出直接检测到类似系统的祖细胞。
Early JWST spectroscopic campaigns have confirmed the presence of strong [O III] line-emitting galaxies in the redshift interval $7<z<9$. Although deduced earlier from Spitzer photometry as indicative of young stellar populations, some studies suggested the relevant photometric excesses attributed to [O III] emission could, in part, be due to Balmer breaks arising from older stars. We demonstrate that this is likely the case by exploiting medium-band near-infrared JWST photometry in the Hubble Ultra Deep Field. We locate a sample of 6 galaxies with redshifts 8.2$<z<$8.6 for which the relevant medium-band filters enables us to separate the contributions of [O III] emission and a Balmer break, thereby breaking earlier degeneracies of interpretation. The technique is particularly valuable since it provides photometric redshifts whose precision, $Δ\,z\simeq\,\pm0.08$, approaches that of spectroscopic campaigns now underway with JWST. Although some sources are young, a third of our sample have prominent Balmer breaks consistent with stellar ages of $\geq$150 Myr. Our results indicate that even intense [O III] emitters experienced episodes of earlier star formation to $z\sim$10 and beyond, as is now being independently deduced from direct detection of the progenitors of similar systems.
