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Description
To avoid the pseudo-evolution problem of the traditionally defined halo mass and radius, we measure the splash-back radius (Rsp), a physically defined halo radius for many halos, using the shear catalog of the DECaLS DR8. The dark matter halos cover the mass of 10^13 - 3 × 10^15Msun and the redshift of 0.08–0.65. Our finding reveals a trend wherein massive halos demonstrate a larger Rsp, and the normalized Rsp (Rsp/R200m) shows a U-shaped mass evolution. The upturn in these relations mainly comes from the contribution of massive halos with low redshifts. We further find the Rsp increases with the peak height, while the normalized Rsp has a negative relation with the peak height. We also find that Rsp >~ R200m for most halos, indicating their low accretion rates. Our result is consistent with previous literature across a wide range of mass, redshift, and peak height, as well as the simulation work from More et al.
