论文标题
原始黑洞丰度的原始磁场的限制
Limits on primordial magnetic fields from primordial black hole abundance
论文作者
论文摘要
原始磁场（PMF）是可行的候选者之一，可以解释观察到的大规模磁场，例如，层状磁场。我们提出了一种新的机制，该机制将根据原始黑洞（PBH）丰富的小尺度带来有关PMF的信息。 PMF的各向异性应力可以充当早期宇宙中超类曲率扰动的来源。如果PMF的幅度足够大，则最终的密度扰动也具有较大的幅度，因此，PBH的丰度得到增强。由于PMF的各向异性应力由磁场的平方组成，因此密度扰动的统计数据遵循非高斯分布。假设PMFS的高斯分布和Delta功能类型的功率谱，基于蒙特卡洛方法，我们获得了密度扰动的近似概率密度函数，这是将PMF振幅与PBH的丰富度相关的重要部分。最后，我们将PMF的最强限制放在$ 10^{2} \; {\ rm mpc}^{ - 1} \ leq k \ leq 10^{18} {18} \; {\ rm mpc}^{ - 1} $ cosm cosm上。
Primordial magnetic field (PMF) is one of the feasible candidates to explain observed large-scale magnetic fields, for example, intergalactic magnetic fields. We present a new mechanism that brings us information about PMFs on small scales based on the abundance of primordial black holes (PBHs). The anisotropic stress of the PMFs can act as a source of the super-horizon curvature perturbation in the early universe. If the amplitude of PMFs is sufficiently large, the resultant density perturbation also has a large amplitude, and thereby, the PBH abundance is enhanced. Since the anisotropic stress of the PMFs is consist of the square of the magnetic fields, the statistics of the density perturbation follows the non-Gaussian distribution. Assuming Gaussian distributions and delta-function type power spectrum for PMFs, based on a Monte-Carlo method, we obtain an approximate probability density function of the density perturbation, and it is an important piece to relate the amplitude of PMFs with the abundance of PBHs. Finally, we place the strongest constraint on the amplitude of PMFs as a few hundred nano-Gauss on $10^{2}\;{\rm Mpc}^{-1} \leq k\leq 10^{18}\;{\rm Mpc}^{-1}$ where the typical cosmological observations never reach.
