Parent Simulation

Initial Conditions

First we constructed a parent simulation of sufficient size to include thousands of Milky Way sized systems but also of sufficient resolution to construct good Lagrangian volumes. We decided on ~10,000 particles per Milky Way-sized host and a 100 Mpc/h volume. Our level_max=10 , which means our parent simulation’s effective resolution is (2^10)^3 = 1024^3, i.e. a parent particle mass,

$$m_p = 8.72 \times 10^7 M_\odot$$

# parentics.conf
[setup]
boxlength               = 100
zstart                  = 127
levelmin                = 10
levelmin_TF             = 10
levelmax                = 10
padding                 = 8
overlap                 = 4
ref_center              = 0.5, 0.5, 0.5
ref_extent              = 0.2, 0.2, 0.2
align_top               = yes
baryons                 = no
use_2LPT                = no
use_LLA                 = no
periodic_TF             = yes

[cosmology]
Omega_m                 = 0.3175
Omega_L                 = 0.6825
Omega_b                 = 0.049
H0                      = 67.11
sigma_8                 = 0.8344
nspec                   = 0.9624
transfer                = eisenstein

[random]
seed[10]                = 34567

[output]
format                  = gadget2
filename                = ./ics
gadget_num_files        = 128

[poisson]
fft_fine                = yes
accuracy                = 1e-5
pre_smooth              = 3
post_smooth             = 3
smoother                = gs
laplace_order           = 6
grad_order              = 6