Austin, Camilla. WP 10202. 

Last week (alog 61603) when TJ and I swapped the masks on the CO2Y table to be the nominal central and annular masks, the rotation stage was not responsive. Daniel power cycled both rotation stages using a Beckhoff OFF/ON switch and it started working. We searched for home for CO2Y but this will need to be done next time CO2X is on. Also both calibrations should be checked and adjusted. 

The CO2 beam was still centered on the irises- as expected as nothing has been changed in this enclosure since O3. We found the annular mask was well aligned with the beam but the central mask was off center (photo).  It was probably off center in O3 as hasn't been adjusted since then. We adjusted the central masks height and re-centered. Photos attached of the beam with no masks, central mask and annular mask.