Attached is a trend of the IPSs for ETMx back 15 days showing the Actuator attachment followed by the IAS-is-good time for ETMx, and the HEPI locked period during the Dome install & work platform removal. The HEPI is then unlocked and finally yesterday is seen when JimW went in to lock the ISI for TMS work. Jim reports he had to hang a bit on ISI Stage0 (HEPI) and there is a good shift on the trends at that time.
So the HEPI aligned for IAS numbers are:
| Pier | Horz | Vert |
| 1-NW | -11500 | 6900 |
| 2-SW | 7500 | -6900 |
| 3-SE | 1200 | 1560 |
| 4-NE | 2200 | -7760 |
The calibration for these channels is 655cts/0.001" so more than a couple 1000 counts starts getting significant for aligned position particularly for Yaw. In light of this, note on the trend where H1 sees a 2500ct shift following the ISI lock. If this were seen on all four corners acting together, this move would approach 50urads. As these are in local coordinates and all are negative, this is more like a de-stressing manifestation. If corners 1 & 3 were negative and the other two corners were positive, we might be getting some real rotations. As it is, taking the signs into account, the shift that appears large on these plots is just 7urads. For the apparently large vertical shift, differentials would be tilts. The largest being 500cts gives about 0.025mm at the pier or ~9urads.
Bottom line, alignment should still be good.
