标题： JWST-CEERS中高红移星系透镜诱导对齐的初步证据 显示英文标题

标题： Preliminary Evidence for Lensing-Induced Alignments of High-Redshift Galaxies in JWST-CEERS

摘要： 在高红移（$z>1$）处，大多数低质量（$\log_{10} M_*/M_{\odot}=9-10$）星系在投影中显得细长。 我们利用JWST-CEERS观测来探索引力透镜在此谜题中的作用。 典型的星系-星系透镜剪切$\gamma\sim1\%$太低，无法解释椭率$e\approx0.6$的早期星系的主导性细长现象。 然而，使用贝叶斯加法回归树的非参数分位数回归显示，存在切向对齐的源-透镜对过多的迹象，具有$\gamma>10\%$。 在更大尺度上，我们也发现了弱透镜剪切的证据。 我们在多个NIRCam芯片、模块和指向中以$\gtrsim99\%$显著性水平排除了随机取向星系的零假设。 此类区域的数量较少，可归因于偶然，但一致的对齐模式表明并非如此。 在芯片尺度上，平均复椭率$\langle e\rangle\sim10\%$是不可忽略的，并超过了我们的PSF不确定性的水平。 剪切方差 $\langle\overline{\gamma}^2\rangle\sim10^{-3}$是传统弱引力透镜区域的一个数量级，但对点扩散函数系统误差、固有对齐、宇宙方差和其他偏差更敏感。 将其作为上限，所暗示的“宇宙剪切”最大值仅为几个百分比，无法解释早期星系的拉长形状。 这些对齐可能来源于在$z\sim0.75$处的原星系团或丝状结构的引力透镜效应，我们在该处发现大量大质量透镜星系的过量。 我们建议使用詹姆斯·韦伯太空望远镜和罗曼空间望远镜对“空白”深场中的过密区域进行弱引力透镜搜索。 显示英文摘要

摘要： The majority of low-mass ($\log_{10} M_*/M_{\odot}=9-10$) galaxies at high redshift ($z>1$) appear elongated in projection. We use JWST-CEERS observations to explore the role of gravitational lensing in this puzzle. The typical galaxy-galaxy lensing shear $\gamma\sim1\%$ is too low to explain the predominance of elongated early galaxies with ellipticity $e\approx0.6$. However, non-parametric quantile regression with Bayesian Additive Regression Trees reveals hints of an excess of tangentially-aligned source-lens pairs with $\gamma>10\%$. On larger scales, we also find evidence for weak lensing shear. We rule out the null hypothesis of randomly oriented galaxies at $\gtrsim99\%$ significance in multiple NIRCam chips, modules and pointings. The number of such regions is small and attributable to chance, but coherent alignment patterns suggest otherwise. On the chip scale, the average complex ellipticity $\langle e\rangle\sim10\%$ is non-negligible and beyond the level of our PSF uncertainties. The shear variance $\langle\overline{\gamma}^2\rangle\sim10^{-3}$ is an order of magnitude above the conventional weak lensing regime but is more sensitive to PSF systematics, intrinsic alignments, cosmic variance and other biases. Taking it as an upper limit, the maximum implied ``cosmic shear'' is only a few percent and cannot explain the elongated shapes of early galaxies. The alignments themselves may arise from lensing by a protocluster or filament at $z\sim0.75$ where we find an overabundance of massive lens galaxies. We recommend a weak lensing search for overdensities in ``blank'' deep fields with JWST and the Roman Space Telescope.