末次散射面中的皱纹：非均匀复合引起的非高斯性
Crinkles in the last scattering surface: Non-Gaussianity from inhomogeneous recombination
摘要：
复合过程中电子数密度的扰动通过二阶项对宇宙微波背景双谱有贡献。电子密度的扰动可以比大尺度上的重子密度涨落大5倍，如Novosyadlyj的计算所示。这提出了这样的可能性，即由光学深度中的扰动引起的对双谱的贡献可能是不可忽略的。我们计算了这个双谱，发现它在压缩三角形处有峰值，峰值振幅为局域型原始非高斯量级，fNL为0.05 ~ -1，这取决于所考虑的l模。这是因为双谱的形状不同于原始的，虽然它的峰值压缩配置，类似于本地类型的原始非高斯。
英文摘要：
The perturbations in the electron number density during recombination contributes to the Cosmic Microwave Background bispectrum through second order terms. Perturbations in the electron density can be a factor of ~5 larger than the baryon density fluctuations on large scales as shown in the calculations by Novosyadlyj. This raises the possibility that the contribution to bispectrum arising from perturbations in the optical depth may be non-negligible. We calculate this bispectrum and find it to peak for squeezed triangles and of peak amplitude of the order of primordial non-Gaussianity of local type with fNL of 0.05 ~ -1 depending on the l-modes being considered. This is because the shape of the bispectrum is different from the primordial one although it peaks for squeezed configurations, similar to the local type primordial non-Gaussianity.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
