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Message ID: 51     Entry time: Wed Jan 2 07:45:39 2013
Author: Koji 
Type: Optics 
Category: Characterization 
Subject: First Contact test 

Conclusion: Good. First contact did not damage the coating surface, and reduced the loss


- Construct a cavity with A1 and C2

- Measure the transmission and FWHM (of TEM10 mode)

- Apply First Contact on both mirrors

- Measure the values again


Transmission:

2.66 +/- 0.01 V -> 2.83  +/- 0.01 V

==> 6.3% +/- 0.5 % increase

FWHM of TEM10:

Before: (66.1067, 65.4257, 66.1746) +/- (0.40178, 0.38366, 0.47213) [kHz]
After: (60.846, 63.4461, 63.7906) +/- (0.43905, 0.56538, 0.51756) [kHz]

==> 5.1% +/- 2.7% decrease

Question: What is the best way to measure the finesse of the cavity?

Attachment 1: Cav_scan_response_zoom_20121125_C2_before.pdf  122 kB  | Hide | Hide all
Cav_scan_response_zoom_20121125_C2_before.pdf
Attachment 2: Cav_scan_response_zoom_20121125_C2_after.pdf  131 kB  | Hide | Hide all
Cav_scan_response_zoom_20121125_C2_after.pdf
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