Sheon looked at these results as part of the DET scattered light technical noise review. His keen eyes noticed that also the second order scattering shelf (correponding to a beam that bounce twice from the moving bench), is also visible.

This can be included in the model, and adds another free parameters, the fraction of scattered light that see the given bench twice. The result are as follow:

• SDB1 0.002ppm (first order) and 2e-7ppm (second order)
• SDB2 0.0004ppm and 3e-8ppm (it is not clear if it is a measurement or an upper limit)
• SNEB 0.03ppm and 1e-6ppm
• SWEB 0.005ppm and 2e-6ppm

Note that for SWEB the second order scattering is 2 times larger than for SNEB, if though the first order scattering is 6 times smaller than for SNEB.