The power per logarithmic interval of k, as defined in Eq. (47), at redshifts z = 0.35, 1, and 3. The symbols are the results from the numerical simulations described in Sect. 4. The black solid line is the linear power spectrum, , and the blue dotted line that is somewhat below at high k is the 2-halo contribution (27), . The steep solid line is the 1-halo contribution (35), for the halo model described in Sect. 3.2. The green solid line is the full nonlinear power spectrum, . The dashed (resp. dotted) green line, that is slightly larger (resp. smaller) at high k, is the result obtained by using the concentration relation for c(M) given by Dolag et al. (2004) (resp. Duffy et al. 2008) instead of Eq. (42). The magenta dot-dashed line , that is somewhat below these new N-body results at high k, is the fit to older simulations from Smith et al. (2003).