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New entries since:Wed Dec 31 16:00:00 1969
Entry  Thu Jun 13 12:04:57 2013, Koji, General, General, [LLO] OMC Optical Test - completed 
Entry  Mon Jun 10 10:04:37 2013, Koji, General, General, [LLO] OMC Test OMC_pow_cal.pdfresponsivity.pdfOMC_pow_cal_compensated.pdf
[Koji Zach]
We worked on the OMC test over the weekend.
- At the beginning, the measured OMC transmission was ~85% even after subtracting the junk light and sidebands from the calculation.
Entry  Thu Jun 13 12:12:20 2013, Zach, General, General, [LLO] OMC and OMCS in LVEA 
Entry  Fri Jun 7 16:04:44 2013, Koji, General, General, [LLO] OMC arrived 
[Koji Zach Suresh]
The OMC arrived at LLO without any destruction!

    We found that one shock sensor on the box turned red, the other stayed white.
    We brought the Perican case to the changing
Entry  Tue Jun 18 15:45:38 2013, Koji, General, General, [LLO] OMC installation in HAM6 
OMC installed in HAM6!
Entry  Wed Mar 20 09:38:02 2013, Zach, Optics, Characterization, [LLO] OMC test bench modified new_setup_traced.jpg
 For various reasons, I had to switch NPROs (from the LightWave 126 to the Innolight Prometheus).
I installed the laser, realigned the polarization and modulation
optics, and then began launching the beam into the fiber, though I have not coupled any light yet.
Entry  Fri Aug 16 17:21:38 2013, Koji, General, General, [OMC002] Build started 
[Jeff Koji]

The breadboard (SN2) was loaded on the transportation fixture.

The laser side template was installed and the cavity mirrors were placed.
Entry  Thu Feb 22 20:21:02 2018, Koji, Optics, Characterization, aLIGO EOM test 
    Reply  Mon Apr 2 17:27:04 2018, Koji, Optics, Characterization, aLIGO EOM test 
2nd optical test http://nodus.ligo.caltech.edu:8080/40m/13725
Entry  Tue Nov 15 07:46:58 2022, Camille Makarem, Optics, General, cleaning OMC #1 
Monday, November 14, 2022

Camille and Koji did a "deep cleaning" of OMC#1:
1) Applied First Contact to the mirror surfaces. Removed first contact after ~10 minutes.
Entry  Tue Mar 5 19:37:00 2013, Zach, Optics, Characterization, eLIGO OMC visibility vs. power measurement details eOMC_visibility_3_4_13.png
EDIT (ZK): Koji points out that (1 - Ti) should really be the non-resonant reflectivity of the aligned cavity, which is much closer to 1. However,
it should *actually* be the non-resonant reflectivity of the entire OMC assembly, including the steering mirror (see bottom of post). The steering mirror
has T ~ 0.3%, so the true results are somewhere between my numbers and those with (1 - Ti) -> 1. In practice, though, these effects are swamped by the
    Reply  Wed Mar 6 23:24:58 2013, Zach, Optics, Characterization, eLIGO OMC visibility vs. power measurement details TEK00005.PNGTEK00007.PNGeOMC_visibility_3_4_13.pngeOMC_AMTF_vs_power_3_6_13.png
I found that, in fact, I had lowered the modulation depth since when I measured it to be 0.45 rads --> Psb = 0.1.
Here is the sweep measurement:
Entry  Wed Apr 10 00:40:30 2013, Zach, Optics, Configuration, fauxMC locked fauxMC_labeled.jpg
[Koji, Zach]
Tonight, we locked the "fauxMC". We obtained
a visibility of >99%.
    Reply  Thu May 16 12:41:28 2019, Chub, General, General, fire pillow found on optics table 
That is an expanding fire pillow, also known as firebrick.  It is used to create a fire block where holes in fire-rated walls are made and prevents
lab fires from spreading rapidly to adjacent labs.  I had to pull cable from B254 to our labs on either side during a rather narrow window of time. 
Some of the cable holes are partially blocked, making it difficult to reach the cable to them. The cable is then just guided to the hole from a distance. 
Entry  Mon Nov 14 08:34:45 2022, Camille, Optics, Characterization, transmission measurements through OMC #1 (before cleaning) PXL_20221111_200942943.jpgPXL_20221111_200957951.jpg
[Camille, Koji]

Friday, Nov 11th, 2022

Setting up OMC #1 for transmission measurements:
    Reply  Mon Nov 14 09:27:13 2022, Koji, Optics, Characterization, transmission measurements through OMC #1 (before cleaning) OMC_Powerbudget.xlsx
The measured total optical loss of the OMC was

1st:   0.015 +/- 0.003
2nd: 0.085  +/- 0.005
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