As reported in entry 2399, there was an earthquake in March 16th around 5 am.
I went to check the setup and it seems that at least the imaging unit is misaligned (moved by few 10 um in distance to the translation stage and the red beam was misaligned by ~ 1 cm to the left on the photodiode). I'll try to characterize the beam again after maximizing the red and IR beams on the photodiode/powermeter.
Also, I suspect that there was some troubles with the computer as :
- several errors messages on the LabView program referring to troubles with the translation stage
- waveplate moved around the earthquake time but no errors
- the chopper frequency changed to 1kHz.