Total luminosity measured from (27, 40) × (0.42π, 0.58π) × (0.81π, 0.96π) (i.e., the simulation domain up to r = 40.0) as a function of time. The red, orange, purple, and green solid lines are for mass fallback rates with f _Edd = 0.01, 0.1, 1.0, and 10.0, respectively. The cyan line shows the smaller collision angle of 90° with f _Edd = 1.0. The blue line shows the larger collision radius of r _coll ≈ 95r _s with f _Edd = 1.0.