While performing particle calculations using il.snapshots.loadHalo, I noticed that summing the masses up the DM, gas, star, wind, and BH in R_500c gives a value slightly less than the FOF group M_500c for most halos (< 1 % lower generally). What could this be attributed to? My error, numerical rounding, unbound particles or something else? Thank you
Dylan Nelson
16h
The spherical overdensity values (like R500c) in the catalogs are computed using all particles/cells in the snapshots, not just the particles that belong to the FoF halo.
You could repeat your calculation with such "global scope" and check if this is the cause.
Hello Dylan,
While performing particle calculations using il.snapshots.loadHalo, I noticed that summing the masses up the DM, gas, star, wind, and BH in R_500c gives a value slightly less than the FOF group M_500c for most halos (< 1 % lower generally). What could this be attributed to? My error, numerical rounding, unbound particles or something else? Thank you
The spherical overdensity values (like R500c) in the catalogs are computed using all particles/cells in the snapshots, not just the particles that belong to the FoF halo.
You could repeat your calculation with such "global scope" and check if this is the cause.