40m QIL Cryo_Lab CTN SUS_Lab CAML OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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New entries since:Wed Dec 31 16:00:00 1969
ID Datedown Author Type Category Subject Text Attachments
  626   Mon Nov 27 21:05:51 2023 KojiGeneralGeneralInventory: C30655 PDsThe Cage H&I, as well as OMC DCPD bag,
were brought to the 40m for the 40m BHD.

  625   Mon Nov 13 23:57:55 2023 KojiElectronicsLoan / LendingAgilent 4395A Network Analyzer -> WB251Aidan and Hanna wanted to use the Agilent
4395A Network Analyzer at the WB251.
All the connections were removed.
  624   Mon Sep 18 15:09:55 2023 Thejas OpticsCAvity BondingPiezo inertial micromatersNew piezo actuated micrometers from thorlabs
arrived last week. 

4 x MPIA10
  623   Mon Sep 18 15:08:26 2023 Thejas OpticsGeneralOMC HEPA enclosure filter fan speedI went in lab today and turned the HEPA
filter (clsoe to the entrance) to high since
we are not doing any measurements at the
  622   Thu Sep 14 14:26:51 2023 Camille MakaremElectronicsCharacterizationRemaining PZT testsPZTs 31, 32, 35, 40 and 45 have had their
DC responses measured (pre-reliability test)
and have been through the reliability test
  621   Wed Aug 30 12:38:52 2023 Thejas OpticsGeneralA+ OMC #1: HOM spectrumExamination into bonding template confimred
the limitation of space available to
change cavity length by at least 10 mm to
  620   Tue Aug 29 16:54:46 2023 KojiFacilityGeneralLED Strip installed[JC, Koji]

We've installed the LED strips
on the HEPA frame. We tried not to touch
  619   Fri Aug 25 22:01:29 2023 KojiFacilityGeneralLED Strip installation planHere are the dimensions of the LED strips
and their gaps.
  618   Thu Aug 24 16:09:46 2023 Camille MakaremOpticsGeneralPZT length-to-angle coupling[Camille, Thejas]

We checked the length-to-angle coupling
  617   Thu Aug 24 12:30:58 2023 Camille Makarem, Thejas OpticsCharacterizationFSR and TMS analysisAttached are the analysis results from
the measurements in 616.
FSR: 264.657354 +/- 0.003444 MHz
  616   Wed Aug 23 07:48:14 2023 Camille Makarem, TejasOpticsCharacterizationFSR and TMS measuarement of A+ build[Camille, Thejas]
22 August 2023
  615   Tue Aug 22 15:51:15 2023 KojiGeneralGeneralInventory: C30655 PDsDuring the OMC(004) assembly, the stock
situation for Excelitas C30655 PDs was checked.

PD Cage H
  614   Tue Aug 22 10:25:10 2023 ThejasOpticsCharacterizationcavity realignment and new power measurementsThanks Koji, we did observe this discrepency
and thought that the code normalizes the
power/voltage readings to the reference power
  613   Mon Aug 21 16:15:09 2023 KojiOpticsCharacterizationcavity realignment and new power measurementsYou should proceed to the next steps. You'll
need to repeat the power measurements before
the bonding. Next time, the measurement procedure
  612   Mon Aug 21 16:05:07 2023 Camille MakaremOpticsCharacterizationcavity realignment and new power measurementsThanks for clarifying that. We will repeat
some power measurements and check the output
offset voltage to the laser.
  611   Mon Aug 21 15:02:32 2023 KojiOpticsGeneralcavity realignment and new power measurementsThis is WOW!

Excellent mode matching work.

The measurement is still
  610   Mon Aug 21 07:59:40 2023 Camille MakaremOpticsGeneralcavity realignment and new power measurements[Camille, Thejas]
18 August 2023
  609   Thu Aug 17 09:06:51 2023 Camille MakaremOpticsGeneralrealignment of beam path through mode-matching lenses[Camille, Thejas]
16 August 2023
  608   Thu Aug 17 07:57:12 2023 Camille MakaremOpticsGeneralmode-matching in the cavity[Camille, Thejas, Koji]
16 August 2023
  607   Tue Aug 15 16:15:13 2023 Camille MakaremOpticsGeneralnew power measurements (after cleaning)[Camille, Thejas, Masayuki]

This afternoon we finished the realignment
  606   Mon Aug 14 14:13:34 2023 Camille MakaremOpticsGeneralmode-mismatch in the cavityFor Set 1 of the data in https://nodus.ligo.caltech.edu:8081/OMC_Lab/604,

VREFL(unlocked) = 3.226V
VREFL(locked) = 0.13V
  605   Mon Aug 14 07:52:11 2023 Camille MakaremOpticsGeneral2nd cleaning of the cavity optics[Camille, Thejas]
11 August 2023
  604   Fri Aug 11 10:42:05 2023 Camille MakaremOpticsCharacterizationpower budget measurements[Camille, Thejas]
10 August 2023
  603   Thu Aug 10 12:33:42 2023 Camille MakaremOpticsGeneraloptimizing the cavity post-cleaning[Camille, Thejas]

This morning, we continued the efforts
  602   Wed Aug 9 17:00:52 2023 Camille MakaremOpticsGeneralcleaning the cavity optics[Camille, Thejas]

We inspected surfaces of the cavity
  601   Wed Aug 9 07:47:21 2023 Camille, ThejasOpticsGeneralsteering the beam spot on the curved mirrors[Camille, Thejas, Masayuki]
8 August 2023
  600   Tue Aug 8 10:42:11 2023 ThejasOpticsGeneralsteering the beam spot on the curved mirrorsThe spots look quite bright on the CMs,
we need to move the spots towards the center
of the mirorrs to avoid scatter points.
  599   Tue Aug 8 09:38:14 2023 KojiOpticsGeneralREFL CCD imageIt has a higher-order mode, but you can
still extract TEM00 from this beam.
e.g., See a past reflection image
  598   Tue Aug 8 07:39:17 2023 Camille MakaremOpticsGeneralsteering the beam spot on the curved mirrors[Camille, Thejas]
7 August 2023
  597   Tue Aug 8 07:30:49 2023 Camille MakaremOpticsGeneralREFL CCD image[Camille, Thejas]
7 August 2023
  596   Mon Aug 7 16:01:05 2023 KojiGeneralGeneralOMC (004): Production completedOMC (004) Production completed. The OMC
together with the transport fixture is still
placed at the 40m clean room.
  595   Mon Aug 7 16:00:30 2023 KojiGeneralGeneralOMC (004): Cable installation The writing of this elog is still on going

[Dean, Stephen, Koji]

  594   Mon Aug 7 08:51:56 2023 Camille MakaremOpticsGeneraloptimizing reflected signalWe will plan to look at the reflection
CCD image this afternoon.

  593   Mon Aug 7 08:37:59 2023 KojiOpticsGeneraloptimizing reflected signalWith the current level of the mode
matching, the spot positions can be optimized.
I'd work on it first as the mirror RoC
  592   Mon Aug 7 07:40:33 2023 Camille MakaremOpticsGeneraloptimizing reflected signal[Camille, Thejas] 4 August 2023

-REFL PD signal (unlocked): 3.5V
  591   Mon Aug 7 07:36:09 2023 Camille MakaremGeneralGeneralparticle count[Camille, Thejas]

We lowered the setting to MEDIUM on
  590   Thu Aug 3 15:24:28 2023 KojiOpticsGeneralA+OMC mode-matching efficiencyThe amount of the reflected beam is a function
of the mode matching and the cavity loss.
  589   Thu Aug 3 15:15:29 2023 ThejasOpticsGeneralA+OMC mode-matching efficiencyThe cavity falls out
of lock very often when subjected to slight
movements of objects on the optic table.
  588   Thu Aug 3 15:04:26 2023 StephenGeneralGeneralaLIGO Unit 4 Build, Cable Routing, Preparation[Dean, Stephen]

Unit #4 aLIGO OMC unit
was transported to the 40m Bake Lab.
  587   Thu Aug 3 10:31:55 2023 ThejasOpticsGeneralA+ OMC build: beam spot positions 

  586   Thu Aug 3 09:42:36 2023 ThejasOpticsGeneralOMC Lab HEPA air filter noise Koji mentioned that previously sarisfactory
particle count was not acheived with the
Med/Med HEPA filter setting once the enclosure
  585   Thu Aug 3 07:22:19 2023 Camille MakaremGeneralGeneralparticle count and cavity optimization/alignmentYesterday, we measured the particle count
in the enclosure to ensure that the lower
setting on one of the HEPAs is still acceptable.
  584   Wed Aug 2 07:32:28 2023 Camille Makarem, Thejas OpticsGeneralSetting up electronics and locking the cavity[Camille, Thejas, Masayuki, Koji]

Previously, we were using the function
generator to drive the laser without using
  583   Tue Aug 1 11:04:13 2023 Camille MakaremGeneralGeneralreoptimizing cavity alignment before locking[Camille, Thejas]
We rechecked the alignment this morning
and re-optimized the resonance a bit. There
  582   Mon Jul 31 13:19:14 2023 Camille MakaremGeneralGeneralplans for this week 31 July 2023Plans for this week:
1) Verify electronics setup for cavity
  581   Sat Jul 29 12:05:52 2023 Thejas OpticsGeneralA+ OMC unit 1 build: Resonance achieved [Camille, Thejas]

Steps followed to acheive this
  580   Wed Jul 26 15:01:26 2023 Madeline LesovskyOpticsGeneralSubassembly Bonding Effort - Oven Bake Profile ResultsThe bonding efforts were conducted on Thursday,
July 13, 2023 (https://nodus.ligo.caltech.edu:8081/OMC_Lab/561)

The duration of the air bake in
  579   Wed Jul 26 12:14:53 2023 Camille MakaremOpticsConfigurationSwapping Subassemblies While using mirror SN14 and mirror SN30
for CM1 and CM2 respectively, we monitored
the two beam spots on FM2 and continued to
  578   Tue Jul 25 23:39:07 2023 ThejasOpticsGeneralA+ OMC unit 1: CM positions swappedWith CM #30 at CM1 position and CM #14
at CM2 postion, when the beam spot on the
CM1 is a little lower than the central line
  577   Tue Jul 25 11:03:13 2023 ThejasOpticsGeneralA+ OMC Unit 1 Cavity BuildThis readjustment to the input beam involved
adjusting the persicope mirorrs and sterring
mirror. We estimate that this will have changed
ELOG V3.1.3-