D. Babusci et al., ALIGNMENT PROCEDURE FOR THE VIRGO INTERFEROMETER - EXPERIMENTAL RESULTS FROM THE FRASCATI PROTOTYPE, Physics letters. A, 226(1-2), 1997, pp. 31-40
A small fixed-mirror Michelson interferometer has been built in Frasca
ti to experimentally study the alignment method that has been suggeste
d for VIRGO. The experimental results fully confirm the adequacy of th
e method. The minimum angular misalignment that can be detected in the
present setup is 10 nrad/root Hz.