论文标题
斧头微量散值很容易
Axion Miniclusters Made Easy
论文作者
论文摘要
我们使用峰值贴片游览集形式主义的修改版本来计算从从轴弦衰减的数值模拟中获得的完全非高斯初始密度字段的QCD轴微量散发器的质量和尺寸分布。我们发现与N体模拟的计算成本大大降低。我们采用球形塌陷模型，并为辐射时代的修饰屏障提供拟合功能。 The halo mass function at $z=629$ has a power-law distribution $M^{-0.6}$ for masses within the range $10^{-15}\lesssim M\lesssim 10^{-10}M_{\odot}$, with all masses scaling as $(m_a/50μ\mathrm{eV})^{-0.5}$.我们构建合并树以估计倒塌红移和浓度质量关系，$ c（m）$，使用初始功率谱和线性生长的分析结果很好地描述了。使用校准的分析结果推断至$ z = 0 $，我们的方法预测平均浓度$ c \ sim \ mathcal {o}（\ text {ligt}）\ times10^4 $。我们方法的低计算成本使得将来对罕见，密集的微量簇的统计数据易于实现。
We use a modified version of the Peak Patch excursion set formalism to compute the mass and size distribution of QCD axion miniclusters from a fully non-Gaussian initial density field obtained from numerical simulations of axion string decay. We find strong agreement with N-Body simulations at a significantly lower computational cost. We employ a spherical collapse model and provide fitting functions for the modified barrier in the radiation era. The halo mass function at $z=629$ has a power-law distribution $M^{-0.6}$ for masses within the range $10^{-15}\lesssim M\lesssim 10^{-10}M_{\odot}$, with all masses scaling as $(m_a/50μ\mathrm{eV})^{-0.5}$. We construct merger trees to estimate the collapse redshift and concentration mass relation, $C(M)$, which is well described using analytical results from the initial power spectrum and linear growth. Using the calibrated analytic results to extrapolate to $z=0$, our method predicts a mean concentration $C\sim \mathcal{O}(\text{few})\times10^4$. The low computational cost of our method makes future investigation of the statistics of rare, dense miniclusters easy to achieve.
