根据质量分辨率计算粒子数 2022-10-28 COSMOLOGY 小记~ 前提假设:其平均密度ρˉ\bar{\rho}ρˉ都是一样的! 根据作为参考的模拟: Npart128~~~\text{Npart}_{128} Npart128= 1283128^31283 Boxsize128~~~\text{Boxsize}_{128} Boxsize128= 20Mpc/h m⊙128=2.837×108 h−1 M⊙~~~m_\odot^{128}=2.837\times10^8~h^{-1}~M_\odot m⊙128=2.837×108 h−1 M⊙ 计算过程推导: Npart3 ⋅ m⊙Boxsize3=1283 ⋅ 2.837×108203≈7.437×1010\frac{\text{Npart}^3~\cdot~m_\odot }{\text{Boxsize}^3}=\frac{128^3~\cdot~2.837\times10^8}{20^3}\approx 7.437\times10^{10} Boxsize3Npart3 ⋅ m⊙=2031283 ⋅ 2.837×108≈7.437×1010 所以可以得到,对任意已知暗物质质量分辨率、盒子大小的模拟,其粒子数应当: Npart=(7.437×1010 ⋅ Boxsize3m⊙)1/3\text{Npart}=(\frac{7.437\times10^{10}~\cdot~\text{Boxsize}^3}{m_\odot})^{1/3} Npart=(m⊙7.437×1010 ⋅ Boxsize3)1/3