锦鲤池：一个拥有多样尘埃星系（DSFGs）群体的强引力透镜原星系团核心
The Koi Pond: A Strongly Lensed Protocluster Core hosting a Diverse Population of DSFGs
AI总结：
本研究通过JWST和ALMA观测发现强引力透镜原星系团核心“锦鲤池”包含11个多样DSFGs，揭示其形态、质量、尘埃性质差异及多样演化路径，为研究星系演化提供关键样本。
AI中文摘要：
我们呈现詹姆斯·韦布空间望远镜（JWST）和阿塔卡马大型毫米波/亚毫米波阵列（ALMA）对PJ0846+15（即“锦鲤池”）的观测结果，这是一个位于“宇宙正午”时期的强引力透镜原星系团核心。该天区提供了对11个尘埃恒星形成星系（DSFGs）的放大观测视角，所有这些星系均处于红移z=2.67（速度差ΔV=800 km s⁻¹范围内），在投影尺度上延伸超过300千秒差距（kpc），由一个红移z=0.77的前景星系团引力透镜放大。近红外相机（NIRCam）和ALMA 6波段连续谱测量分别以约0.15角秒（″）的空间分辨率绘制了恒星分布和热尘埃辐射图。分析揭示了一个多样的DSFGs群体，存在相互作用和非相互作用系统的证据，呈现出广泛的形态特征，包括旋臂、棒状结构、核球、团块/恒星团、潮汐尾/残骸以及移位的分子气体储库。通过比较静止帧J波段连续谱（F444W）与（i-J）色指数（F277W−F444W），我们发现二者数值范围广泛，表明恒星质量存在超过1个数量级（>1-dex）的弥散，且尘埃消光导致的红化ΔA_V > 1星等（mag）。DSFG成员相对于恒星辐射呈现出不同的尘埃尺度，从致密的尘埃核心到星系尺度的辐射不等。单个源的分辨色图显示F277W−F444W色指数弥散高达2星等，表明恒星与尘埃的几何结构复杂。尽管核心中存在富气体并合，但最红、尘埃辐射最强的成员是具有团块结构的盘状星系，表明 secular（ secular演化）增长可驱动这些星暴事件。该样本中如此显著的性质范围表明，原星系团核心环境中的DSFGs在向宁静椭圆星系团星系转变的过程中遵循多样的演化路径。
英文摘要：
We present James Webb Space Telescope (JWST) and Atacama Large Millimeter Array (ALMA) observations of PJ0846+15, \textit{The Koi Pond}, a strongly lensed protocluster core at Cosmic Noon. This field offers a magnified view of 11 dusty star-forming galaxies (DSFGs) all at $z=2.67$ (within $ΔV=800$ km s$^{-1}$) spanning a projected extent of $>300$ kpc lensed by a $z=0.77$ foreground cluster. NIRCam and ALMA Band 6 continuum measurements map the stellar distribution and thermal dust emission respectively at a spatial resolution of $\sim$0.15$^{\prime\prime}$. This analysis reveals a diverse population of DSFGs, with evidence of both interacting and non-interacting systems exhibiting a wide range of morphological features including spiral arms, bars, bulges, clumps/stellar clusters, tidal tails/debris and displaced molecular gas reservoirs. Comparing the rest-frame J- band continuum (F444W) vs (i-J) color (F277W$-$F444W), we find a wide range of values, suggesting a $>$1-dex spread in stellar mass and a dust attenuation reddening of $ΔA_{\mathrm{V}} > 1$ mag. The DSFG members exhibit varying dust sizes relative to the stellar emission, ranging from compact dusty cores to galaxy-wide emission. Resolved color maps of individual sources showing a spread as high as F277W$-$F444W$=2$ mag suggesting complex stellar-to-dust geometry. Although gas-rich mergers are identified in the core, the most red and dust emitting members are disks exhibiting clumpy structure indicating secular growth can drive these starburst events. Such a remarkable range in properties within this sample suggest DSFGs in protocluster core environments follow diverse evolutionary pathways towards their transition into quiescent, elliptical cluster galaxies.
