The Millennium-XXL (MXXL) N-body simulation uses the same cosmological parameters as the original Millennium simulation, but in a volume 63=216 times as large. Despite the increase in particle number as well, this comes at the cost of a lower mass resolution by a factor of ~7. The simulation was run with a modified version of GADGET3. Further details on the simulation can be found in the paper by Angulo et al. (2012). Currently on TAO, MXXL data products exist as Premade catalogues. These include 2 Light-Cones: one that extends to z=2.2 for halo properties, and one that extends to z=0.8 and includes galaxy properties as assigned by a Halo Occupation Distribution model. These Light-Cones are fully detailed by Smith et al. (2017).
Box length: 3000h-1 cMpc
Relative volume to Millennium and an all-sky survey out to z=0.05:
Particle mass: 6.17 × 109h-1 Msun
Gravitational softening: 10h-1 kpc
Number of particles: 67203
Particle size compared to Millennium:
MXXL has 7.17 times lower mass resolution than Millennium, meaning a Millennium halo contains 7.17 times the number of particles of an MXXL halo of equivalent mass.
ΩM = 0.25
ΩΛ = 0.75
Ωb = 0.045
σ8 = 0.9
n = 1
h = 0.73