matthewrichard.todd@LIGO.ORG - posted 10:58, Tuesday 18 November 2025 - last comment - 09:34, Wednesday 15 April 2026(88155)
Summary Table of OMC Scan and Gouy Phase measurements
M. Todd, J. Wright, S. Dwyer
Here is my attempt to summarize as many of the OMC scan measurements of the input beam overlap with the OMC mode, as well as PRC and SRC gouy phases -- all at different thermal states.
| Measurement | Time | Test Masses | CO2 [W] | Ring Heater (per segment) [W] | SR3 [W] | OM2 [W] | FOM | aLOG |
| OMC Scan - Single Bounce off of ITMY | 1443895154 | Cold | 0 | 0 | 0 | 0 | Mismatch = 8.3% | 87461 |
| OMC Scan - Single Bounce off of ITMX | 1443894875 | Cold | 0 | 0.45 | 0 | 0 | Mismatch = 10.4% | 87461 |
| OMC Scan - Single Bounce off of ITMY | 1443889943 | Cold | 1.7 | 0 | 0 | 0 | Mismatch = 10.3% | 87461 |
| OMC Scan - Single Bounce off of ITMX | 1443894875 | Cold | 1.7 | 0.45 | 0 | 0 | Mismatch = 13.5% | 87461 |
| OMC Scan - Single Bounce off of ITMY | 1431450536 | Cold | 0 | 0 | 5 | 0 | Mismatch = 7.6% | 85661 |
| OMC Scan - Single Bounce off of ITMY | 1403543046 | Cold | 0 | 0 | 0 | 4.6 | Mismatch = 6.6% | 78701 |
| OMC Scan - Single Bounce off of ITMX | 1431449762 | Cold | 0 | 0.45 | 5 | 0 | Mismatch = 9.6% | 85661 |
| OMC Scan - Single Bounce off of ITMY | 1431474471 | Cold | 0 | 0 | 5 | 4.6 | Mismatch = 3.1% | 85698 |
| OMC Scan - Single Bounce off of ITMX | 1431474101 | Cold | 0 | 0.45 | 5 | 4.6 | Mismatch = 5.1% | 85698 |
| OMC Scan - Single Bounce off of ITMY | 1444515634 | Hot-ish | 1.7 | 0 | 0 | 0 | Mismatch = 7.1% | 87461 |
| OMC Scan - Single Bounce off of ITMX | 1444515312 | Hot-ish | 1.7 | 0.45 | 0 | 0 | Mismatch = 8.9% | 87461 |
| OMC Scan - SQZ Beam | 1446952255 | - | - | - | - | 4.6 | Mismatch = 6.8% | 88060 |
| OMC Scan - SQZ Beam | 1447088389 | - | - | - | - | 0 | Mismatch = 2.8% | 88088 |
| Gouy Phase - PRC | 1255227492 | Cold | ITMY = 0.9, ITMX = 0.8 | ITMY = 1.4, ITMX = 0.5 | 0 | 0 | OneWay Gouy Phase = 23.2 [deg] | 52504 |
| Gouy Phase - PRC | 1354415805 | Cold | 0 | 0 | 0 | 0 | OneWay Gouy Phase = 20.7 [deg] | 66215 |
| Gouy Phase - SRC | 1354410195 | Cold | 0 | 0 | 0 | 0 | OneWay Gouy Phase = 19.9 [deg] | 66211 |
| Gouy Phase - SRC | 1255907203 | Cold | ITMY = 0.9, ITMX = 0.8 | ITMY = 1.4, ITMX = 0.5 | 0 | 0 | OneWay Gouy Phase = 25.5 [deg] | 52658 |
| Gouy Phase - SRC | 1255829128 | Cold | ITMY = 0.9, ITMX = 0.8 | ITMY = 1.4, ITMX = 0.5 | 4 | 0 | OneWay Gouy Phase = 29 [deg] | 52641 |
The measurements made with SR3 hot in May 2025 were done with SR3 heater requested power set to 2W, the readback of reported power was 1.9W. The lines in the table that say 5W for SR3 power should say 2W.