[C II] luminosity as a function of halo stellar mass. The panels from left to right display predictions at z = 12, 10, 8, and 6. The solid lines represent the mean values and the darker (lighter) shaded regions represent the 1σ (2σ) standard deviation for CDM Ref (blue), CDM HR (purple), and CDM LB (green). The symbols refer to the ALMA large observational programs ALPINE (squares; Béthermin et al. 2020; Le Fèvre et al. 2020) and REBELS (crosses; Bouwens et al. 2022; Ferrara et al. 2022), which target [C II] emission at z = 4.5 − 6 and z = 6.5 − 7.7, respectively.