These are now the results of the second round for the Ti sample. I rotated the sample by 90 degrees and measured its scattering again.
As can be seen, the peaks are much more sharper and more regular/symmetric compared to the non-rotated sample.
The strange shape of the AOI=0 curve is due to the interpolation process of the data gap (PD cuts off the Laser light) and the fact that I used one data point at theta=0 from older backscattering measurements.I need the interpolation for the implementation of the data into LightTools.