The scans in the comparison reported in elog entry 973 were shifted to make the comparison more clear, but if we plot the original data together (see first plot), we see that the crossing point has shifted after we changed the probe size and pump size.
The shift is between 2.3mm and 3mm, therefore to compare a measurement with the map taken at 50mm (reported in elog entry 678 ) I took a map at 53mm and another one at 52.5mm.
I calculate the ratio between the large beams maps and the small beams maps. See last plot