A quantitative analysis of the effect of box size in N-body simulations of the matter power spectrum

Abstract

We study the effect of box size on the matter power spectrum obtained via cosmological N-body simulations. Within the framework of the cosmic screening approach, we show that the relative deviation between the spectra for our largest comoving box with L = 5632 Mpc/h and those for L = 280, 560, 1680, 4480, 5120 Mpc/h boxes consistently increases with decreasing box size in the latter set in the redshift range $0\le z\le 80$ for the considered values. As an additional demonstrative example, at redshift zero, we determine the values $k_{1\%}$ corresponding to the modes at which relative deviations reach 1\%.

Comments: 8 pages, 2 tables, 3 figures