We present the substellar mass function of star-forming clusters ($\simeq$0.1 Myr old) in a low-metallicity environment ($\simeq$$-$0.7 dex). We performed deep JWST/NIRCam and MIRI imaging of two star-forming clusters in Digel Cloud 2, a star-forming region in the Outer Galaxy ($R_G \gtrsim 15$ kpc). The very high sensitivity and spatial resolution of JWST enable us to resolve cluster members clearly down to a mass detection limit of 0.02 $M_\odot$, enabling the first detection of brown dwarfs in low-metallicity clusters. Fifty-two and ninety-one sources were extracted in mass-$A_V$-limited samples in the two clusters, from which Initial mass functions (IMFs) were derived by model-fitting the F200W band luminosity function, resulting in IMF peak masses (hereafter $M_C$) $\log M_C / M_\odot
\simeq -1.5 \pm 0.5$ for both clusters. Although the uncertainties are rather large, the obtained $M_C$ values are lower than those in any previous study ($\log M_C / M_\odot \sim -0.5$). Comparison with the local open clusters with similar ages to the target clusters ($\sim$$10^6$-$10^7$ yr) suggests a metallicity dependence of $M_C$, with lower $M_C$ at lower metallicities, while the comparison with globular clusters, similarly low metallicities but considerably older ($\sim$$10^{10}$ yr), suggests that the target clusters have not yet experienced significant dynamical evolution and remain in their initial physical condition. The lower $M_C$ is also consistent with the theoretical expectation of the lower Jeans mass due to the higher gas density under such low metallicity. The $M_C$ values derived from observations in such an environment would place significant constraints on the understanding of star formation.
Searching for Extremely Blue UV Continuum Slopes at $z=7-11$ in JWST/NIRCam Imaging: Implications for Stellar Metallicity and Ionizing Photon Escape in Early Galaxies
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）
Unveiling the Cosmic Chemistry II: "Direct" $T_e$-based metallicity of galaxies at 3 $< z <$ 10 with JWST/NIRSpec
Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology（麻省理工学院卡弗里天体物理学与空间研究研究所）；University of Kentucky（肯塔基大学）；University of Virginia（弗吉尼亚大学）
Efficient black hole seed formation in low metallicity and dense stellar clusters with implications for JWST sources
University of Heidelberg（海德堡大学）；Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences（波兰科学院尼古拉·哥白尼天文学中心）；New York University Abu Dhabi（阿布扎比纽约大学）；Sapienza Università di Roma（罗马第一大学）；Universidad de Concepción（康塞普西翁大学）；Universidad de Chile（智利大学）；Chinese Academy of Sciences（中国科学院）
Spatially resolved gas-phase metallicity at z~2-3 with JWST/NIRISS
INAF – Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）；University of California, Los Angeles（加州大学洛杉矶分校）；The Johns Hopkins University（约翰斯·霍普金斯大学）；Space Telescope Science Institute（太空望远镜科学研究所）；University of Oxford（牛津大学）；California Institute of Technology（加州理工学院）；Institut d’Astrophysique de Paris, CNRS, Sorbonne Université（巴黎天体物理研究所，法国国家科学研究中心，索邦大学）；International Centre for Radio Astronomy Research (ICRAR), University of Western Australia（国际无线电天文学研究中心（ICRAR），西澳大学）；Australian National University（澳大利亚国立大学）；ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)（ARC三维全天空天体物理学卓越中心（ASTRO 3D））
The Metallicity Dependence of PAH Emission in Galaxies II: Insights from JWST/NIRCam Imaging of the Smallest Dust Grains in M101
University of Toledo（托莱多大学）；Space Telescope Science Institute（太空望远镜科学研究所）；University of California, San Diego（加州大学圣地亚哥分校）；California Institute of Technology（加州理工学院）；University of Maryland, College Park（马里兰大学帕克分校）；University of Wyoming（怀俄明大学）；Princeton University（普林斯顿大学）
JWST Census for the Mass-Metallicity Star-Formation Relations at z=4-10 with the Self-Consistent Flux Calibration and the Proper Metallicity Calibrators
Exploring the ultra-faint dwarf Bootes I using JWST and HST: Metallicity distribution and binaries
Università Degli Studi di Padova（帕多瓦大学）；Istituto Nazionale di Astrofisica - Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）；Research School of Astronomy and Astrophysics, Australian National University（澳大利亚国立大学天文与天体物理研究学院）；South-Western Institute for Astronomy Research, Yunnan University（云南大学西南天文研究所）
The JWST EXCELS Survey: gas-phase metallicity evolution at 2 < z < 8
University of Edinburgh（爱丁堡大学）；University of California（加州大学）；NSF’s National Optical-Infrared Astronomy Research Laboratory（美国国家光学-红外天文研究实验室）；Armagh Observatory and Planetarium（阿尔马天文台和天文馆）；University of the Western Cape（西开普敦大学）；Space Telescope Science Institute（太空望远镜科学研究所）
JADES: Detecting [OIII]$λ4363$ Emitters and Testing Strong Line Calibrations in the High-$z$ Universe with Ultra-deep JWST/NIRSpec Spectroscopy up to $z \sim 9.5$
Diverse ionized gas conditions in a dynamically hot, interacting galaxy at $z = 9.31$ revealed by JWST/NIRSpec IFU
Leiden University（莱顿大学）；Tohoku University（东北大学）；INAF–Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Space Telescope Science Institute（太空望远镜科学研究所）；Johns Hopkins University（约翰斯·霍普金斯大学）；University of Maryland, College Park（马里兰大学帕克分校）
The ALPINE-CRISTAL-JWST Survey: Gas-phase abundance gradients of main sequence star-forming galaxies and their kinematics at $4 < z < 6$
Max-Planck-Institut für extraterrestrische Physik (MPE)（马克斯·普朗克地外物理研究所）；David A. Dunlap Department of Astronomy and Astrophysics, University of Toronto（多伦多大学天文学与天体物理学戴维·A·邓拉普系）；Dunlap Institute for Astronomy and Astrophysics（邓拉普天文学与天体物理研究所）；IPAC, California Institute of Technology（加州理工学院行星科学与红外处理中心）；Departamento de Astronomía, Universidad de Concepción（康塞普西翁大学天文学系）；Millenium Nucleus for Galaxies (MINGAL)（星系千年核心（MINGAL））；Departments of Physics and Astronomy, University of California, Berkeley（加州大学伯克利分校物理与天文学系）；Osservatorio Astronomico di Padova（帕多瓦天文台）
研究利用JWST观测分析4 < z < 6的20个主序星系气体相金属licity梯度及其运动学特性，发现金属licity梯度与盘状结构成熟度相关，且在宇宙晚期时间中金属licity梯度呈现负趋势。
JWST's PEARLS: Temperatures of Nine Highly Magnified Stars in a Galaxy at Redshift 0.94 and Simulated Stellar Population Dependence on Stellar Metallicity and the Initial Mass Function
Revealing the spiral arms through radial migration and the shape of the Metallicity Distribution Function
最近的观测显示，银河系的金属丰度分布函数（metallicity distribution function，简写为ψ）会随着半径的变化而改变其形状。这一星盘内径向迁移的新证据对银河系模型提出了额外的限制。通过在一个非常详细的，观测动机的银河系模型中进行受控的测试粒子模拟，我们证明，在盘的内部区域中，由酒吧和螺旋臂的共同作用，而在外半径，主要是由螺旋臂的形状，形成的？我们表明，旋臂能够印上他们的签名在径向迁移，塑造在银河系盘的外围的酒吧的最小参与。相反，这项工作有可能根据径向迁移和螺旋形状来确定螺旋臂的一些结构和动力学参数。最后，用这种近似方法得到的与APOGEE观测到的银河系曲率曲线的相似性表明，影响它们形状的一个基本因素是银河系势。
The Sunburst Arc with JWST: I. Detection of Wolf-Rayet stars injecting nitrogen into a low-metallicity, $z=2.37$ proto-globular cluster leaking ionizing photons
Gas-Phase Metallicity and Nitrogen Abundances in Low-Mass Galaxies Down to $M_\star\simeq10^{5.7}\,M_\odot$ at $z\simeq4.5$--$10.1$ from JWST Lensing Cluster Surveys
University of Tsukuba（筑波大学）；The University of Tokyo（东京大学）；National Astronomical Observatory of Japan（日本国立天文台）；Kanazawa University（金泽大学）；SOKENDAI (The Graduate University for Advanced Studies)（综合研究大学院大学）
JWST & ALMA Joint Analysis with [OII]$λλ$3726,3729, [OIII]$λ$4363, [OIII]88$μ$m, and [OIII]52$μ$m: Multi-Zone Evolution of Electron Densities at $\mathbf{z\sim0-14}$ and Its Impact on Metallicity Measurements
