OMC scan with the X-arm locked beam was performed. Data is being analyzed with the script kindly provided by guru Koji Arai (we need to optimize his fitting script for this carrier exisiting omc scan). I might re-measure it sometime this week depending on the result.
Data files (xml) are in
/users/Commissioning/data/OMC/CavityScan/
with today's date.
To varify the HOM fitting result (which will be posted soon), we indentified which peak is which mode. Please see the attachment for result. The second, third, fourth higherst peaks are higher order modes of the carrier fields. The modes were identified looking at a cavity scan video comparing the OMC DC PD A signal. The attached camera movie (OMC trans) is correspoing to the attached OMC data in ndscope.
[Koji Arai, Kokeyama]
OMC Scan Result
The incident light is with the X arm locked. OMC finesse was measued as roughly 580. The power in each mode is shown below.
| Carrier Sub tota | Upper 17MHz sidebands | Lower 17MHz sidebands | Upper 45MHz sidebands | Lower 45MHz sidebands |
|
order mW
CA0: 9.4
CA1: 0.38
CA2: 0.62
CA3: 0.26
CA4: 0.10
CA5: 0.015
CA6: 0.025Sub total
order mW
CA0: 9.247, 9.6409 => 9.4
CA1: 0.38
CA2: 0.62
CA3: 0.26
CA4: 0.10
CA5: 0.015
CA6: 0.025
Upper 17MHz sidebands
order mW
0 0.040
1 0.013
2 0.0026
Lower 17MHz sidebands
order mW
0 0.041
1 0.013
2 0.0023
Upper 45MHz sidebands
order mW
0 0.049814
1 0.014056
2 0.003407
Lower 45MHz sidebands
order mW
0 0.053
1 0.017
2 0.0043
|
order: mW
SB0: 0.040
SB1: 0.013
SB2: 0.0026
|
order: mW
SB0 0.041
SB1 0.013
SB2 0.0023
|
order: mW
SB0 0.050
SB1 0.014
SB2 0.0034
|
order: mW
SB0 0.053
SB1 0.017
SB2 0.004
|
See the detailed result in the attached text file.
Carrier Sub total
order mW
CA0: 9.247, 9.6409 => 9.4
CA1: 0.38
CA2: 0.62
CA3: 0.26
CA4: 0.10
CA5: 0.015
CA6: 0.025
Upper 17MHz sidebands
order mW
0 0.040
1 0.013
2 0.0026
Lower 17MHz sidebands
order mW
0 0.041
1 0.013
2 0.0023
Upper 45MHz sidebands
order mW
0 0.049814
1 0.014056
2 0.003407
Lower 45MHz sidebands
order mW
0 0.053
1 0.017
2 0.0043
Carrier Sub total
order mW
CA0: 9.247, 9.6409 => 9.4
CA1: 0.38
CA2: 0.62
CA3: 0.26
CA4: 0.10
CA5: 0.015
CA6: 0.025
Upper 17MHz sidebands
order mW
0 0.040
1 0.013
2 0.0026
Lower 17MHz sidebands
order mW
0 0.041
1 0.013
2 0.0023
Upper 45MHz sidebands
order mW
0 0.049814
1 0.014056
2 0.003407
Lower 45MHz sidebands
order mW
0 0.053
1 0.017
2 0.0043
Identified Modes
- See the previous post for the identified mode for carrier 0-3th order.
- Identified +-f1 and +-f2 sideband positions in the scan is shown in the attached first png figure.
Varifying the identified Modes
- We measured the cavity scan without f1 sideband (with Nakano-kun's help in the mine). See the second png figure. Comparing with and without f1 SBs, peaks where f1 SBs should be correspond the assumed f1 SB positions shown in the first figure. Because the scan direction was opposite, the order sof the modes are flipped.
- For the carrier, see the previous post.
Fitted plot, detailed mode identification, and PZT-frequency calibration are attached as pdf.
You let me see a resonance curve with fitting curves for many TEM00 and its harmonics resonances.
By subtracting the fitting data except for USB3? that is very near TEM00 from the measured data, can you see a small residual peak near the TEM00 resonance frequency ?
Updating the results.