JWST/NIRSpec Spectroscopy of $z=7-9$ Star Forming Galaxies with CEERS: New Insight into Bright Ly$α$ Emitters in Ionized Bubbles
Mengtao Tang, Daniel P. Stark, Zuyi Chen, Charlotte Mason, Michael Topping, Ryan Endsley, Peter Senchyna, Adèle Plat, Ting-Yi Lu, Lily Whitler, Brant Robertson, Stéphane Charlot
备注:
31 pages, 22 figures, accepted by MNRAS, references updated
我们描述了来自CEERS巡天的对z≳7星系的新JWST/NIRSpec观测。该区域先前的观测揭示了在红移z=7.5、7.7、8.7处Lyα发射体的成协现象,而这些红移处星际介质(IGM)被认为大部分是中性,这导致人们提出这些系统位于大型电离泡中。我们在CEERS数据集中识别出21个具有可靠红移的z≳7星系,其中包括10个位于Lyα成协中的星系。它们的光谱表明气体高度电离且金属贫乏,具有在较低红移处很少见到的谱线比(O32=17.84和Ne3O2=0.89,线性标度)和金属丰度(12+log(O/H)=7.84)。我们发现样本中六个z≳7 Lyα发射体具有最极端的谱线性质。每个都具有硬电离谱,表明它们的可见性可能因高效的电离光子产生而增强。Lyα速度偏移被发现非常大(≳300 km s⁻¹),可能也有助于它们的可探测性。我们发现z≳7星系中的Lyα比具有匹配静止光学谱线性质的较低红移样本弱6-12倍。如果Lyα发射体周围的电离泡相对较小(≲0.5-1 pMpc),我们可以预期在这些电离区域中Lyα会出现如此显著的衰减。我们讨论了可能导致z≳7处Lyα发射较弱的其他几种效应。对Lyα发射体附近较暗星系进行深度光谱观测将更好地刻画该场中电离泡的物理尺度。
英文摘要:
We describe new JWST/NIRSpec observations of galaxies at $z\gtrsim7$ taken from the CEERS survey. Previous observations of this area have revealed associations of Ly$α$ emitters at redshifts ($z=7.5$, $7.7$, $8.7$) where the intergalactic medium (IGM) is thought to be mostly neutral, leading to suggestions that these systems are situated in large ionized bubbles. We identify 21 $z\gtrsim7$ galaxies with robust redshifts in the CEERS dataset, including 10 in the Ly$α$ associations. Their spectra are indicative of very highly ionized and metal poor gas, with line ratios (O32 $=17.84$ and Ne3O2 $=0.89$, linear scale) and metallicity ($12+\log{(\rm{O/H})}=7.84$) that are rarely seen at lower redshifts. We find that the most extreme spectral properties are found in the six $z\gtrsim7$ Ly$α$ emitters in the sample. Each has a hard ionizing spectrum indicating that their visibility is likely enhanced by efficient ionizing photon production. Ly$α$ velocity offsets are found to be very large ($\gtrsim300$ km s$^{-1}$), likely also contributing to their detectability. We find that Ly$α$ in $z\gtrsim7$ galaxies is $6-12\times$ weaker than in lower redshift samples with matched rest-optical spectral properties. If the bubbles around the Ly$α$ emitters are relatively small ($\lesssim0.5-1$ pMpc), we may expect such significant attenuation of Ly$α$ in these ionized regions. We discuss several other effects that may contribute to weaker Ly$α$ emission at $z\gtrsim7$. Deep spectroscopy of fainter galaxies in the vicinity of the Ly$α$ emitters will better characterize the physical scale of the ionized bubbles in this field.
Galaxy-scale lens search in the PEARLS NEP TDF and CEERS JWST fields
University of Melbourne(墨尔本大学);ARC Centre of Excellence for All-Sky Astrophysics in 3 Dimensions (ASTRO 3D)(三维全天空天体物理学卓越研究中心);Arizona State University(亚利桑那州立大学);Instituto de Fisica de Cantabria (CSIC-UC)(坎塔布里亚物理研究所);Space Telescope Science Institute(太空望远镜科学研究所)
Simulating and interpreting deep observations in the Hubble Ultra Deep Field with the JWST/NIRSpec low-resolution 'prism'
詹姆斯·韦伯太空望远镜(JWST)将能够探测星系中的光发射线,其亮度范围很广,红移z>10。通过这些观测,对星系的关键特性(如恒星形成率和金属丰度)的测量将提供独特的见解,例如,来自恒星和活动星系核(AGN)的反馈在调节星系演化中的作用,AGN和宿主星系的共同演化,恒星形成星系的“主序列”的物理起源以及恒星形成星系对宇宙再电离的贡献。我们提出了一个原始的框架来模拟和分析观测与近红外光谱仪(NIRSpec)上JWST。我们使用的BEAGLE工具(贝叶斯分析的GalerosEds)建立一个半经验的星系光谱目录的基础上的光度光谱能量分布(SED)的辍学星系在哈勃超深场(HUDF)。我们证明,由此产生的星系光谱目录满足不同类型的高红移星系的观测约束,并使用它作为输入,以模拟NIRSpec/棱镜(R~100)的观测。我们发现,一个单一的“深”(~100 ks)的近红外光谱/棱镜指向HUDF将使S/N>3检测的多个光学发射线在~30(~60)星系在z>6(z~4-6)下降到m_F160 W <30 AB MAG。这样的观测将允许测量星系恒星形成率,电离参数和气相金属丰度的1.5倍,质光比在2倍之内,星系年龄在3倍之内,V波段衰减光学深度的精度为0.3。
Adding Value to JWST Spectra and Photometry: Stellar Population and Star Formation Properties of Spectroscopically Confirmed JADES and CEERS Galaxies at $z > 7$
本文分析 43 个 JADES/CEERS 经光谱证认的 $z>7$ JWST 星系,联合 SED 拟合、光谱线、测光与形态信息,揭示其上升的恒星形成历史、测光 EW 偏差及近期星暴贡献。
Breaking Through the Cosmic Fog: JWST/NIRSpec Constraints on Ionizing Photon Escape in Reionization-Era Galaxies
University of Geneva(日内瓦大学);Niels Bohr Institute, University of Copenhagen(哥本哈根大学尼尔斯·玻尔研究所);Cosmic Dawn Center (DAWN)(宇宙黎明中心(DAWN));Max Planck Institut für Astrophysik(马克斯·普朗克天体物理研究所);Max-Planck-Institut für Astronomie(马克斯·普朗克天文学研究所);The University of Texas at Austin(德克萨斯大学奥斯汀分校)
The BoRG-$JWST$ Survey: Abundance and Mass-to-light Ratio of Luminous $z=7-9$ Galaxies from Independent Sight Lines with NIRSpec
University of California, Los Angeles(加州大学洛杉矶分校);The University of Texas at Austin(德克萨斯大学奥斯汀分校);University of Geneva(日内瓦大学);California Institute of Technology(加州理工学院);National Astronomical Research Institute of Thailand (NARIT)(泰国国家天文研究所);Niels Bohr Institute, University of Copenhagen(哥本哈根大学尼尔斯·玻尔研究所);Max Planck Institut für Astronomie(马克斯·普朗克天体物理研究所);University of Melbourne(墨尔本大学)
Direct T_e-based Metallicities of z=2-9 Galaxies with JWST/NIRSpec: Empirical Metallicity Calibrations Applicable from Reionization to Cosmic Noon
University of Kentucky(肯塔基大学);University of California, Davis(加州大学戴维斯分校);University of California, Los Angeles(加州大学洛杉矶分校);University of Arizona(亚利桑那大学);University of California, Riverside(加州大学河滨分校);Cosmic Dawn Center (DAWN)(宇宙黎明中心);Niels Bohr Institute, University of Copenhagen(哥本哈根大学尼尔斯·玻尔研究所)
The Supermassive Black Hole in the Nearby Spiral Galaxy M81: A Robust Mass from JWST/NIRSpec Stellar Dynamics
University of Michigan(密歇根大学);Vietnam National University – Ho Chi Minh City(越南国立大学胡志明市);University of Oxford(牛津大学);International University, Vietnam National University in Ho Chi Minh City(越南国立大学胡志明市国际大学)
Measuring the Central Dark Mass in NGC 4258 with JWST/NIRSpec Stellar Kinematics
University of Michigan(密歇根大学);University of Science, Vietnam National University in Ho Chi Minh City(越南国立大学胡志明市自然科学大学);University of Oxford(牛津大学);International University, Vietnam National University in Ho Chi Minh City(越南国立大学胡志明市国际大学);International Centre for Interdisciplinary Science and Education(跨学科科学与教育中心)
The AURORA Survey: Tracing Galactic Outflows at $z\gtrsim2.5$ with JWST/NIRSpec NUV Absorption Lines
University of California, Los Angeles(加州大学洛杉矶分校);University of Kentucky(肯塔基大学);University of California, Riverside(加州大学河滨分校);University of Edinburgh(爱丁堡大学);University College London(伦敦大学学院);University of California Davis(加州大学戴维斯分校);Rochester Institute of Technology(罗切斯特理工学院);University of Florida(佛罗里达大学);University of Geneva(日内瓦大学)
The JWST Ultramassive Galaxy Sample -- II. Supermassive Black Hole Masses for 8 Extreme Early-Type Galaxies via Jeans Anisotropic Modelling of High-Resolution Integral-Field NIRSpec Stellar Kinematics
University of Oxford(牛津大学);University of Michigan(密歇根大学);Space Telescope Science Institute(太空望远镜科学研究所)
本研究利用 JAM 建模 JWST 高分辨率 NIRSpec 恒星运动学,测量 8 个超大质量星系的中心黑洞质量,发现其增长具有高度随机性,并填补了极端质量标度关系的空白。
MOCSS: Multi-Object Coronagraphy for JWST/NIRSpec Slitless Spectroscopy
University of Minnesota(明尼苏达大学);Stockholm University(斯德哥尔摩大学);Space Telescope Science Institute(太空望远镜科学研究所);University of Texas at Austin(德克萨斯大学奥斯汀分校);University of Modena & Reggio Emilia(摩德纳与雷焦艾米利亚大学);University College London(伦敦大学学院);Williams College(威廉姆斯学院)
Spatial decomposition of Little Red Dots with JWST/NIRSpec IFU into broad-line red cores and narrow-line blue host galaxies
Massachusetts Institute of Technology(麻省理工学院);University of Hawai‘i(夏威夷大学);Institute of Science and Technology Austria (ISTA)(奥地利科学技术研究所);North Carolina State University(北卡罗来纳州立大学);The University of Texas at Austin(德克萨斯大学奥斯汀分校);Princeton University(普林斯顿大学)
JADES NIRSpec Initial Data Release for the Hubble Ultra Deep Field: Redshifts and Line Fluxes of Distant Galaxies from the Deepest JWST Cycle 1 NIRSpec Multi-Object Spectroscopy