Doc D0901920 lists the cavity length as 3994.485 m (as built, anyone?). The attached Mathematica snipped calculates the axial location of the sidebands.
The as-built distance for the X-arm cavity according to IA (Jason & Doug) is 3994.472 ± 0.004 m.
I would like to get an accurate X arm cavity length measurement when we do a cavity characterization. I have ask JAX if she had some time for this after we pump down. She did this during the HIFOy test. This along with the survey as built numbers would help verify the BTVE-8 (gold standard) monument position at the X-end station with its relationship to the BTVE-5 in the corner station. We would incorporate data from the ITMx survey monuments based on their as built position to the BTVE-5. We would possibly gain a more accurate measurement of the distance between the BTVE monuments for the future.