jason.oberling@LIGO.ORG - posted 16:40, Wednesday 13 March 2013 (5784)
Power Recycling Cavity Alignment Summary
A summary of the current state of the PR cavity optics alignment. Due to the small yaw angle of each optic the directions listed in parentheses with each lateral and longitudinal position error are only approximate and should only be used as a guide to roughly visualize the direction of the error.
PR2
PR2 alignment has been completed, the positional/angular errors are:
-
Longitudinal Error: +0.3 mm (North)
- Tolerance: ±3 mm
-
Lateral Error: -0.1 mm (East)
- Tolerance: ±1 mm
-
Vertical Error: -0.02 mm (low)
- Tolerance: ±1 mm
-
Pitch Error: 45 µrad up
- Tolerance: ±100 µrad
- Target: 0.0 µrad
- Actual Pitch: 45 µrad up
-
Yaw Error: 48 µrad CW
- Tolerance: ±100 µrad
- Target: +8.092 mrad (CW w.r.t. x-axis)
- Actual Yaw: +8.14 mrad (CW w.r.t. x-axis)
PR3
PR3 positional alignment is complete. Since the setup for PR3 and PRM positional alignments are almost identical we decided to align PRM position before doing PR3 pitch/yaw. PR3 positional errors are:
-
Longitudinal Error: +2.8 mm (North)
- Tolerance: ±3 mm
-
Lateral Error: -0.5 mm (East)
- Tolerance: ±3mm
-
Vertical Error: +2.4 mm (high)
- Tolerance: ±3 mm
PRM
An initial look at PRM position alignment was taken today; longitudinal and lateral position only. The errors are currently:
-
Longitudinal Error: -4.9 mm (South)
- Tolerance: ±3 mm
-
Lateral Error: -1.56 mm (East)
- Tolerance: ±2 mm
Tomorrow we will measure the PRM vertical position error, make any shifts of the PRM that are required, and then move on to PR3 pitch/yaw alignment.