Figure A2.

The analytical simulation method is described with a flow chart (letter labels are consistent with figure A1). In Step 1, (a)–(d) (n = 1) are calculated. In Step 2, convolution/superposition is used in a loop to calculate (e) and (f) for n = 2–6. For each loop, the scattered photons (e) are used as the starting point (d) for the next iteration. In Step 3, (g) is calculated by summing over (c) and (f) (n = 2–6).