Travis S., Betsy B., Jeff G.

Today,more mechanical adjustments on the H2 ITMY QUAD were made today.  The diagonalization measurements were run on the M0 and R0 top masses for the Vertical and Yaw degrees of freedom.  Results attached.

M0 Vertical isolation = ~18dB
M0 Yaw isolation = ~17dB

R0 Vertical isolation = ~7dB
R0 Yaw isolation = ~11dB

Dave B., Richard M., Filiberto C., Jeff G.
The SUS H2 ITMY Simulink model h2susitmy.mdl was modified today to accommodate the L2 (UIM) AOSEM signals. On the h2susb478 machine, the first ADC card's "cardNum" is designated 0 (zero) in the Simulink model; the second ADC "cardNum" is 1 (one). The previous version of the h2susitmy model routed the ITMY PUM signals to the first ADC card on the h2susb478 machine. According to the latest BS, ITM, and FM Suspensions Controls Wiring (D1001725-v9), the PUM controls wiring should be routed to the second ADC card ("cardNum" = 1) on the h2susb478 machine.  The appropriate changes were made to h2susitmy.mdl to reroute the PUM signals to "cardNum=2".  The new version was compiled and make installed onto h2susb478.  

The signals were confirmed on the H2 ITMY PUM by medm readout.  The AOSEMs now can to be normalized and centered to the flags.

Attached are plots of dust counts > .5 microns.

Today, Travis moved 62g from the AR side of the UIM to the HR (which was already the heavy side of the mass) in order to free up more range on the pitch roll bar adjusters.  This did the trick and brought the pitch in to ~100uRAD.  We then moved on to aligning the UIM and PUM OSEM/flag pairs.  This was immediately problematic in that the signals of these 8 OSEMs looked strange.  Richard help us diagnose that the L1 (UIM) signals were connected to the L2 (PUM) MEDM and vice versa.  This was remedied via switching the 25pin 225 cable connections at the feedthru panel.  Unfortunately, there were more troubles with L2.  Dave discovered a DUO tone channel in the wrong place, and Garcia had some residual code changes to make.  This recovered 3 of the 4 L2 channels, but there was still one that looked fishy.  Garcia is investigating it more tonight.  I am crossing my fingers that it is not the quadra-puss cable on the QUAD.

I was able to align and set the 2 lower BOSEMs of the UIM to 50% OLV, but was running out of range on the uppers when the LVEA went laser safe and I quit for the night.  

More alignment  ...to be continued.

Yesterday, seismic restarted testing HAM-ISI in the staging building. It seems that one of the horizontal GS13 is malfunctioning. The symptoms are similar to those we see when the proof mass is stuck (no low frequency response but high frequency response looks OK). After hitting the GS13 with a wrench and handling it, the mass is still stuck. I have attached Powerspectra of the 3 horizontal geophones when the ISI is locked (H3 geophone is the bad one).

Today we moved the ETM Quad-04 to the Y end station. The Lower Structure weighed 539lbs and the Upper Structure weighed 255lbs. Total weight for the metal build of Quad-4 is 794lbs, which should be close to its’ final weight. The next step is to mount the Upper Structure to BSC-6 and prep the Lower Structure for the monolithic build.  

Diagonalization measurements were run last night and today on the M0 and R0 top masses on H2 ITMY.  

For the M0 Yaw DoF, the non-Yaw OSEMs are about ~15dB isolated from M0 Yaw.  The drive was a 1.3Hz sine wave with a 250ct amplitude. The measurement resolution was 0.02Hz.

For the M0 Vert DoF, the non-Vert OSEMs are about ~19dB isolated from M0 Vert. The drive was a 2.25Hz sine wave with a 1000ct amplitude. The measurement resolution was 0.02Hz.

For the R0 Yaw DoF, the non-Yaw OSEMs are about ~21dB isolated from R0 Yaw.  The drive was a 1.3Hz sine wave with a 250ct amplitude. The measurement resolution was 0.02Hz.

For the R0 Vert DoF, the non-Vert OSEMs are ONLY ~6-7dB isolated from R0 Vert. The drive was a 2.25Hz sine wave with a 1000ct amplitude. The measurement resolution was 0.02Hz.

I had to tighten a connector in the front panel of the HV module for the injection locking. Therefore I switched off the injection locking for a few minutes to do that work. After finishing the laser is now running injection locked again.

MichaelR and RickS

Today we leveled the FSS path beam at the 10 cm optical height (centered on lenses and irises).
The mount for the AOM does not allow it to go low enough with the beam level, so we replaced it temporarily with the eLIGO AOM mount sitting on 1" spacers.  We will modify the aLIGO mount and replace it ASAP.

We set up the FSS path to use the frequency upshifted beam and adjusted the alignment to get the following powers with the VCO mod level set at Max (32767):
47 mW incident on the AOM
33 mW in single pass (upstream of curved mirror M25)
20.5 mW double pass (downstream of PBSC and first turning mirror M26)

42% double pass efficiency.  Not great. We did not check the beam size at the AOM or the RF power delivered to the AOM.

We installed irises in both the single-pass and double-pass paths to block the unwanted diffraction orders.

Attached are plots of dust counts > .5 microns. The dust monitor at end X appears to have alarmed with a sensor failure over the weekend.

Installed awgstream-2.15.4a to temporarily fix a problem of not recognizing all the excitation channels as valid.

All stabilization loops (PMC, FSS, ISS) were locked this week for the first time all together for more than an hour with 154W downstream of the PMC. The frequency stabilization is not optimized yet, because the temperature control of the tank is not installed and the beam downstream of the AOM needs to be realigned. I will post some diagnostic breadboard measurements later this week. 
During installation I misaligned the camera in reflection of the PMC. So no worry, when one beam image is missing on the TV screen.

[Patrick, Jan]
We traced the 12kHz oscillation that we were struggling with down to the problem that there is no impedance in the output of the AI filters. This caused a oscillation at high frequencies which apparently coupled into the PZT ramp signal (ramp is generated digitally). We build an adapter with 100 Ohm resistors between input and output of the 24 channels and this solved the problem. Since this problem is also present in all other channels (PMC, ISS, FSS) we will look for some board redesign or adapters for those channels too (currently in discussion with Peter King)

X1 QUAD 04 BUILD 03
Brett S., Jeff B., Andres R., Jeff G. 

Cabling adjustments were made on the QUAD 04 BUILD 03 to reduce the effect of the cable routing on the Pitch DoF for the R0 chain. Evidence of cabling affecting Pitch on R0 is detailed in an earlier post.  DTT whitenoise transfer function measurements were taken between adjustments to cable arrangements to assess the cabling effect on Pitch.

The attached pdf is of the M0 and R0 top mass transfer functions taken via Matlab for the six Euler-basis DoFs.

The previous measurements on the attached plots are the same as in the previous post:
ORANGE - H2SUSITMY, "Before Lacing"
BLACK - H2SUSITMY, "After Lacing 1"
MAGENTA - H2SUSITMY, "After Lacing 2"
CYAN - X1SUSQUAD04, "Before Lacing"
GREEN - X1SUSQUAD04, "After Lacing 1"
RED - X1SUSQUAD04, "After Lacing 2" - (Latest Measurement)
 
For the M0 chain, the latest measurement is identical.  This is to be expected since M0's cabling was not changed.

For the R0 chain, the L, T, V, R, and Y DoFs are identical between the latest X1 QUAD 04 measurements on 11/19/2011 and 11/22/2011.  The concern was that the cabling stiffened the Pitch DoF such that the lowest resonant modes shifted to higher frequencies after cabling (see page 11 - CYAN vs. GREEN).  However, it is evident the latest cabling adjustments helped reduce QUAD 04 R0 Pitch's stiffness such that it's lowest resonant modes closely match the H2 ITMY Pitch DoF after it's lacing was completed (page 11).

Parameters for the 11/19/2011 and 11/22/2011 measurements were identical drive and response.

QUAD 04 BUILD 03 Diagonalization

The diagonalization measurements on the QUAD 04 BUILD 03 M0 and R0 masses were performed again after recent cabling work from the previous week.  The attached plots are of both the M0 and R0 top masses for the Vertical and Yaw degrees of freedom.

For the M0 mass, both the Vertical and Yaw degrees of freedom are ideally isolated at near ~30dB from the other OSEMs.  The Vertical drive was a sine wave at 2.25Hz with 100cts of amplitude.  The Yaw drive was a sine wave at 1.3Hz with 100cts of amplitude.

For the R0 mass, both the Vertical and Yaw degrees of freedom are isolated at roughly ~24dB from the other OSEMs.  The Vertical drive was a sine wave at 2.25Hz with 100cts of amplitude.  The Yaw drive was a sine wave at 1.3Hz with 100cts of amplitude.

These results indicate the QUAD 04 M0 and R0 top mass OSEMs are diagonalized ideally.

Attached are plots of dust counts > .5 microns.

Removed 200g from left and 50g from right on back of PenRe in order to bring reaction chain up to height of main chain.  Looks good by eye now.  Realigned all R0 BOSEMs.  PenRe AOSEMs still need alignment.
Adjusted top mass pitch to see if pitch TF cleaned up.  It didn't.  Put it roughly back.
Added UIM flags which resulted in an hour long headache of trying to get a trapped set screw out of the new UIM flag mounts.  (Will need to adjust assembly procedure to only use one of the 2 available on each flag, and unfortunately it's not the same one in each case due to assymetry of the mount part.)  The UIM BOSEMs are not yet aligned to the flags, but the weight is there.
Due to the mucking around of pitch on both chains, Jason remeasured the angles and found that the ITMy was at 2.45mRAD up, and the CP was at 1.67mRAD down.  Since it was at the UIM that flags were added causing the midpitch, I rolled the UIM pitch adjusters out (toward the HR) by 1 turn each.  Jason then measured the ITMy pitch to be 2.09 mRad up.

Will resume after Thanksgiving.


 

Activities on-site:

-Drilling for I/O beam tube for H2 in LVEA - might have caused some excess dust counts near the ISI/SUS test stand cleanroom.

-Adjustments/testing on H2 ITMY QUAD

- There was a call from the Praxair delivery truck just before noon, however they did not come to the gate.

A dusty event occurred today just before lunch time in the LVEA.  There are three dust monitors that were triggered - "H0:PEM-LVEA_DST11_*", "H0:PEM-LVEA_DST3_*", and "H0:PEM-LVEA_DST4_*".  There was a strip tool plot running that was noticed in the Control Room, however "H0:PEM-LVEA_DST4_*" data cannot be trended in dataviewer at this time.  The attached .jpg is of the "H0:PEM-LVEA_DST11_*" and "H0:PEM-LVEA_DST3_*" dust monitors for the >0.3 and >0.5 micron triggers.  

The two plotted dust monitors are in two separate locations.  "H0:PEM-LVEA_DST11_*" is located outside the ISI/SUS test stand cleanroom between it and HAM 10.  "H0:PEM-LVEA_DST3_*" and "H0:PEM-LVEA_DST4_*" are located INSIDE the ISI/SUS test stand cleanroom near the ITMY.

The plot indicates the event triggered "H0:PEM-LVEA_DST11_*" about ~2259s before "H0:PEM-LVEA_DST3_*" was triggered.  

The amplitudes in counts during the event for each dust monitor for both >0.3 and >0.5 microns:

"H0:PEM-LVEA_DST11_5" amp = 1730
"H0:PEM-LVEA_DST11_3" amp = 2200
"H0:PEM-LVEA_DST3_5" amp = 400
"H0:PEM-LVEA_DST3_3" amp = 1940

Attached are plots of dust counts > .5 microns during today and yesterday.