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The Low-Redshift Lyman Continuum Survey (LzLCS) is a HST Large program using the Cosmic Origins Spectrograph to provide direct measurements of the ionizing radiation (Lyman continuum LyC) of 66 star-forming galaxies. The completed survey showed that virgul50% of LzLCS galaxies are LyC emitters. Most of these objects are analogous to the high-z galaxies responsible for initiating and sustaining the epoch of reionization (EoR) comma and virgul70% have Lyman-alpha EW>25 Angstrom. However the COS observations are spatially unresolved and capture only light emitted from a vignetted 2.5 arcsec region comma centered upon the galaxies. Here we propose a 119-orbit program to obtain spatially resolved panchromatic imaging of 41 of these galaxies to closely examine the physical properties and geometry of their central and outer regions. We will obtain images in five filters (far-UV to visible) and produce maps of the stellar population and Lyman-alpha emission comma and facilitate numerous investigations relevant for calibrating proxies of LyC output. The program will map the dust obscuration comma star-formation rate and history comma and ionizing stellar properties. These Ly-alpha images will provide essential information regarding the physical state of the ISM and its intimate role in regulating LyC transmission comma by contrasting line and continuum images to test resonance scattering. The combined dataset will provide many unique measurements that are well-aligned with the UV initiative comma have enormous archival utility comma and will produce a dataset that can be applied directly to JWST studies of the EoR.

低红移莱曼连续谱巡天（Low-Redshift Lyman Continuum Survey，LzLCS）是哈勃空间望远镜（Hubble Space Telescope，HST）的一项大型项目，它利用宇宙起源光谱仪（Cosmic Origins Spectrograph，COS）对66个恒星形成星系的电离辐射（莱曼连续谱，LyC）进行直接测量。完成的巡天结果显示，约50%的LzLCS星系为LyC发射体。这些天体大多与负责启动和维持再电离时代（epoch of reionization，EoR）的高红移星系具有相似性，且约70%的天体莱曼α等效宽度（Lyman-alpha EW）大于25埃（Angstrom）。然而，COS观测在空间上未解析，仅捕捉到以星系为中心、2.5角秒区域内发射的光线。为此，我们提议开展一项119轨道的项目，对其中41个星系进行空间分辨的全色成像，以深入探究其中心与外围区域的物理性质及几何结构。我们将通过五个滤镜（覆盖远紫外至可见光波段）获取图像，生成恒星种群及莱曼α发射图谱，并推动与LyC输出代理校准相关的多项研究。该项目将绘制尘埃消光、恒星形成率与历史以及电离恒星性质的分布图。这些莱曼α图像通过对比谱线与连续谱图像来测试共振散射，将提供关于星际介质（interstellar medium，ISM）物理状态及其在调节LyC传输中核心作用的关键信息。合并后的数据集将提供众多独特测量结果，这些结果与紫外倡议高度契合，具有巨大的存档价值，并可直接应用于詹姆斯·韦布空间望远镜（James Webb Space Telescope，JWST）对EoR的研究。