论文标题
来自星系内在比对的原始重力波
Primordial Gravitational Waves from Galaxy Intrinsic Alignments
论文作者
论文摘要
已经观察到星系形状与宇宙大规模结构产生的外部潮汐场保持一致。尽管这些潮汐场的主要来源是由长波长密度扰动提供的，但张量扰动也有助于线性阶时的非变化幅度。我们表明，在通货膨胀期间产生的奇偶校验重力波留下了星系形状功率谱的独特烙印，这不会受到任何标量引起的潮汐场的阻碍。我们还表明，在通货膨胀期间产生的某种张量非高斯量可能会在密度加权的星形形状功率光谱中留下一个特征。我们估计在未来的星系调查中观察到这种烙印的可能性。
Galaxy shapes have been observed to align with external tidal fields generated by the large-scale structures of the Universe. While the main source for these tidal fields is provided by long-wavelength density perturbations, tensor perturbations also contribute with a non-vanishing amplitude at linear order. We show that parity-breaking gravitational waves produced during inflation leave a distinctive imprint in the galaxy shape power spectrum which is not hampered by any scalar-induced tidal field. We also show that a certain class of tensor non-Gaussianities produced during inflation can leave a signature in the density-weighted galaxy shape power spectrum. We estimate the possibility of observing such imprints in future galaxy surveys.
