Steve went over to the MC2 walkway and stepped over the barrier to pick up some stuff there. MC2 stack shifted and MC2 pitch as off. MC unlocked and could not relock till the MC2 pitch bias was readjusted
previous MC2PIT reading: 3.6235 current MC2PIT reading: 3.9565
Without the WFS the MC to PSL alignment is poor, but it is largely due to a shift in the MC and not a shift in the PSL beam. We know this 'coz the shift in the DC spot positions on WFS (when the MC is unlocked) is not significant nor is the shift on the C1:IOO-QPD. When WFS loops are engaged the MC optics are turned to optimise the PSL to MC alignment, but the shift is large at the moment.
(Sorry Mirko your measurement could not be completed. The MC unlocked in the middle)
Please Note: If you need to access the blocked off area near MC2 stack, do not step over the barrier. The disturbance is too great and the MC2 stack will shift. Instead please move the barrier aside and walk as gently as possible near it, taking care not to touch the MC2 Chamber.