论文标题
中微子质量对全功率谱形状影响的简单分析治疗通过两流体近似
A Simple Analytic Treatment of Neutrino Mass Impact on the Full Power Spectrum Shape via a Two-Fluid Approximation
论文作者
论文摘要
在存在大规模中微子的情况下，我们为物质功率谱提供了一种新的封闭式公式，其精度在所有尺度上都高于5 \％。这是所有尺度上有效的第一个闭合形式结果。为了计算这种封闭形式的解决方案，我们使用参数的变化来构建物质对中微子扰动的响应，从中微子质量分数（$f_ν\ ll 1 $）求解流体方程，以及中微子的中微子，$f_ν\ ll 1 $。该分析解决方案加速了用中微子对物质功率谱的计算。同样，它使一个人能够计算物质和中微子的跨功率谱，而中微子又可以用于计算功率谱的高阶校正。为了展示我们的公式的准确性和实用性，我们对其进行了Fisher的预测，并证明我们从Boltzmann求解器类别中重现了预测。
We present a new closed-form formula for the matter power spectrum in the presence of massive neutrinos that gives an accuracy of better than 5\% on all scales. It is the first closed-form result valid on all scales. To calculate this closed-form solution, we iteratively solve the fluid equations for cold dark matter+baryons, and neutrinos in terms of the neutrino mass fraction, $f_ν \ll 1$, using variation of parameters to construct the response of the matter to the neutrino perturbation, which in turn will source the higher-order neutrino perturbations. This analytic solution accelerates calculations of the matter power spectrum with neutrinos. Also, it enables one to calculate the cross power spectra of matter and neutrinos which in turn can be used in computing the higher-order corrections to the power spectrum. To demonstrate our formula's accuracy and utility, we perform a Fisher forecast with it and show we reproduce the forecast from the Boltzmann solver class.
