Does anyone know how is the distance between detectors in the now famous neutrino experiment measured? Also, how was the time of flight measured?
I know that time of flight isn't a problem at all. GPS satellites broadcast an extremely accurate timestamp regularly; that alone will get you within microseconds. You can set up an atomic clock driven countdown weeks in advance and use radio based methods to synchronize things up.
Once you have timestamps, distance isn't much of a problem either. Measure the exact time a gamma ray burst is observed at each location. Do that a few times.
GPS sattelites are not in sync in the Einstein way because
As each sat must be in sync with the one at left side and the one at right side and all with all they share a common time (universal pre-calculated). The GPS system appears to be like an 'instant observer'. The speed of light that is in use in the GPS system is the mean speed of light in a closed path. For a non-Einstein referential (a different synchronization) a complete study of the properties of the light/observer system must be used as was done here and the 'one-way' light speed must be calculated and used. This way the errors will vanish.
The error between using a mean speed or the 'one-way' speed to calculate distances is irrelevant in usual circunstances but not in this stringent situation.