论文标题
关于使用JWST的人口III星系的可观察性和鉴定
On the observability and identification of Population III galaxies with JWST
论文作者
论文摘要
我们利用种群III恒星+nebular光谱的理论模型来研究使用深度成像和光谱法与JWST准确识别种群III星系的前景。我们研究了一系列不同的颜色切割，发现通过F444W-F560W，F560W-F770W颜色的NIRCAM和MIRI光度法组合提供了潜在的$ Z = 8 $ POP III候选者的最强大标识符。我们计算出Nircam必须达到$ \ sim $ 28.5-30.0 ab mag depths（1-20 h），而Miri F560W必须达到$ \ sim $ \ sim $ \ sim $ 27.5-29.0 ab mag depths（10-100 h）才能实现$5σ$ continuum continuum continuum检测$ m_* = 10^6〜 = 10^6〜 \ a $ _____________________ m m} m} m} m} m} m} m} m} m} m} m} m} m} m} c {m} c odot。 $ z = 8 $。我们还讨论了通过无知和NIRSPEC光谱调查鉴定POP III候选者的前景，该调查的目标是$α$，H $β$和/或He II $λ1640$。我们发现POP III和非流行III星系之间的H $β$ REST框架等效宽度（EW）的差异很小，这使此诊断可能不切实际。取而代之的是，我们发现对高EW HE II $λ1640$排放的检测将用作确定的流行III标识符，需要（超）深入整合（10-250 H），将NIRSPEC/g140m $ _*= 10^= 10^6〜 \ MATHRM {M} _ \ odot $ $ _ \ odot $ $ _ \ odot $ pop pop z $ z = 8 $ z = 8 $ z = 8 $ z = 8 $ z = 8 $。但是，流行III星系的Miri F770W检测将需要实质性的重力镜头（$μ= 10 $）和/或偶然的巨大成像（$ M_* = 10^7〜 \ MATHRM {M} _ \ ODOT $）POP III GALAXIES。因此，可以在光度法中搜索高EW的NIRCAM中频成像调查可能是寻找POP III候选者的可行替代方案。
We utilise theoretical models of Population III stellar+nebular spectra to investigate the prospects of observing and accurately identifying Population III galaxies with JWST using both deep imaging and spectroscopy. We investigate a series of different colour cuts, finding that a combination of NIRCam and MIRI photometry through the F444W-F560W, F560W-F770W colours offers the most robust identifier of potential $z=8$ Pop III candidates. We calculate that NIRCam will have to reach $\sim$28.5-30.0 AB mag depths (1-20 h), and MIRI F560W must reach $\sim$27.5-29.0 AB mag depths (10-100 h) to achieve $5σ$ continuum detections of $M_* = 10^6~\mathrm{M}_\odot$ Pop III galaxies at $z=8$. We also discuss the prospects of identifying Pop III candidates through slitless and NIRSpec spectroscopic surveys that target Ly$α$, H$β$ and/or He II $λ1640$. We find small differences in the H$β$ rest-frame equivalent width (EW) between Pop III and non-Pop III galaxies, rendering this diagnostic likely impractical. Instead, we find that the detection of high EW He II $λ1640$ emission will serve as the definitive Pop III identifier, requiring (ultra-)deep integrations (10-250 h) with NIRSpec/G140M for $M_*=10^6~\mathrm{M}_\odot$ Pop III galaxies at $z=8$. However, MIRI F770W detections of Pop III galaxies will require substantial gravitational lensing ($μ=10$) and/or fortuitous imaging of exceptionally massive ($M_* = 10^7~\mathrm{M}_\odot$) Pop III galaxies. Thus, NIRCam medium-band imaging surveys that can search for high EW He II $λ1640$ emitters in photometry may perhaps be a viable alternative for finding Pop III candidates.
