Galaxy imaging surveys provide us with information on both the galaxy distribution and their shapes. In this paper, we systematically investigate the sensitivity of galaxy shapes to new physics in the initial conditions. For this purpose, we decompose the galaxy shape function into spin components, and compute the contributions to each spin component from both intrinsic alignment and weak lensing. We then consider the angular-dependent primordial non-Gaussianity, which is generated by a non-zero integer spin particle when active during inflation, and show that a galaxy imaging survey essentially functions as a spin-sensitive detector of such particles in the early universe. We also perform a forecast of the PNG generated from a higher spin particle, considering a Rubin Observatory LSST-like galaxy survey.

星系成像调查为我们提供了有关星系分布及其形状的信息。在本文中，我们系统地研究了星系形状在初始条件下对新物理的敏感性。为此，我们将星系形状函数分解为自旋分量，并计算固有对齐和弱透镜对每个自旋分量的贡献。然后，我们考虑由非零整数自旋粒子在暴胀期间活跃时产生的与角度相关的原始非高斯性，并表明星系成像调查本质上是早期宇宙中此类粒子的自旋敏感探测器. 考虑到鲁宾天文台类似 LSST 的星系调查，我们还对由更高自旋粒子产生的 PNG 进行了预测。