Noisy day, which permited lots of noisy activities.

• Apollo crew moved cleanroom around in the LVEA with crane, very noisy
• Aidan to End-Y to calibrate HWS, see entry for more information
• Floor work continues at End-X
• Electrician visited all stations
• Late delivery, from NY, 4 skids to large equipment access bay area.
• Apollo used Big Red to move an item from OSB to staging building
• Patrick setup a dust monitor around HAM01 area

[Jax, Aidan, Elli]

This morning we calibrated the lever arm of the HWS. We added a beam splitter (CAL-BS) into the optical path to hit the HWS CCD with two beams (REFL and TRANS) at ~ 10mrad to each other. We removed the Hartmann plate from the sensor and recorded the resulting interference pattern on the CCD. The spatial frequency of the interference pattern allowed us to determine the exact angle between the two beams, 9.86mrad, with a precision of approximately 1:500. Next we replaced the Hartmann plate and measured the Hartmann sensor spot pattern of each beam separately by blocking first one and then the other beam. We centroided the spots and determined the mean centroid displacement, 8.507 pixels. Knowing the measured angle, the pixel size (12E-6 m) and the spot displacement, we determined that the lever arm distance (between the Hartmann plate and the CCD) is 10.35 +/- 0.03mm.

The data is attached. Also attached is an optical layout showing the additional beam splitter producing the reflected and transmitted beams.

We made certain to remove the beam splitter and check the final alignment of the HWS system was restored to nominal before closing up the ETM ALS table.

The reference lever arm that has been used before now is 10.0mm.

Replaced the fuse for the dust monitor in the clean room over HAM 3 (LVEA location 15). Restarted the EPICS IOC.
Added a dust monitor in the clean room over HAM1 and 2 (LVEA location 9).

Collected as much serial number as possible on the nearly completed HAMISI#7 (just a few remaining tests for it).  There was one item I was not able to get, namely the a Flexure; it was oriented in a way that made its s/n NOT viewable (waiting to see if someone jotted this info when they built the system).  Below are all the other s/n's:

Stage0:  014

Stage1:  010

Optics Table:  009 

Corner1

Actuators

• H1:  179
• V1:  097
• H1 Cable:  S1104095
• V1 Cable:  -6677

GS13s

• H1: 009
• V1: 003
• Pigtail Cable:  -4677
• Extension:  -4700

L4Cs

• H1: 006
• V1: 041
• Pigtail Cable:   -4681
• Extension:  -6651

CPS Sensor

• H1: 12009
• V1: 12025

Flexure:  -- not viewable, installed upside-down :(

Spring:  030

Support Post:  031

Corner2

Actuators

• H2:  178
• V2: 118
• H2 Cable: -4098
• V2 Cable: -6682

GS13s

• H2: 061
• V2: 050
• Pigtail Cable: -4679
• Extension:  -6656

L4Cs

• H2: 114
• V2: 052
• Pigtail Cable:  -4687
• Extension:  -6650

CPS Sensor

• H2: 12012
• V2: 12016

Flexure:  046

Spring:  041

Support Post: 017

Corner3

Actuators

• H3: 176
• V3: 007
• H3 Cable:  -6675
• V3 Cable:  -7761

GS13s

• H3: 078
• V3: 053
• Pigtail Cable:  -4686
• Extension:  -4705

L4Cs

• H3: 090
• V3: 0014
• Pigtail Cable:  -4680
• Extension:  -4706

CPS Sensor

• H3: 12036
• V3: 12030

Flexure: 040

Spring:  045

Support Post:  032

B. Bland, J. Garcia, J. Kissel

Attached are plots comparing the recent H1 SUS PR2 Phase 2B measurements against other HSTS in various stages (completing the data package) in order to give a final answer on Phase 2B testing.

As of this entry H1 SUS PR2 passes Phase 2b and is go for install into HAM3, with the following caveats:
(1) Late in the game, the assembly team found an IR filter is missing on an M3 (Bottom) stage AOSEM. The spectra comparisons show that there's little-to-no difference in the response of sensor, i.e. it's functional (as far as you can tell in the noisy chamber-side environment). Regardless, the assembly team are aware of the problem, and will replace that AOSEM once in chamber, as there's plenty of room to play around in there, and it's a simple fix.

(2) It's a long story (so I'll save it for a subsequent comment to this log), but we discovered the same small T to Y cross-coupling at 1.1 and 2.05 Hz on PR2 as was recently discovered on X1 SUS MC3. At the time, (we thought) X1 SUS MC3 was the only SUS that had such cross coupling, and (we knew we) still had lots of chances to debug the issue before install, so we approved his Phase 1b results and agreed to move forward. However, due to the hectic/scattered measurements and turn-on blips of getting the HAM SUS up and running at LHO, the cross coupling in H1 SUS PR2 (formerly X1 SUS PR2) has fallen under the radar up to this point. So, in light of several things:
- (As in seen in the attached TF comparisons, specifically pg 2, the M1 to M1 T to T TFs), ONLY X1 SUS MC3 and H1 SUS PR2 show this particular cross coupling, out of Nine other HSTS that have been built project wide (again further clues, a better zoom, theories, and conjectures to come).
- We will move X1 SUS MC3 chamber-side, and the install team will spend an extended amount of time identifying/debugging the problem where there's plenty of room, and less pressure. Once the problem is solved, they will retroactively make the same changes to H1 SUS PR2 in chamber, where (at least in HAM3) there's a comfortable amount of room to make adjustments.
- Again, the coupling is small, and goes away with damping -- the concern is the model, which we use extensively to predict motion estimates, may not be as accurate.
 
Ease of later documentation, the individual measurements that compose the rest of the package are aLOGged here:
Damping Loops OPEN M1 to M1 TFs: LHO aLOG 3851
Damping Loops CLOSED M1 to M1 TFs: LHO aLOG 3855
Amplitude Spectra of All Stages: LHO aLOG 3861

The overview medm for the TMTS suspension was modified today to correct mislabled channels.  A DC align medm part was ported over from the QUAD medm directory for use in setting DC offsets on the TMTS suspension.  All changes were committed to the cds_user_apps SVN.                                                                         

A report on the measurements of the hydrocarbon residual gas at the y end has been posted
on the LIGO DCC with a document number LIGO T1200395-v1. The hydrocarbon pressure,
now with all the advanced LIGO components in the chamber, raises concern. The data and the
suggestions of actions to take are discussed in the document.

Attached are plots of dust counts > .5 microns in particles per cubic foot.

In order to complete the individual data set for H1 SUS PR2's phase 2B testing, I attach the amplitude spectral densities of all stages of OSEMs. Tough to determine anything from these plots:
 - there's so many dang plots,
 - one is only comparing damping ON vs OFF, so you're only looking for "do the damping loops
       - Damp the resonances
       - Add any unexpected additional noise at any stage"
but given those limited criteria, the answer is "looks fine..."

Stay tuned for comparison with other spectra and a more concrete/final answer.

• Prep work for installing PR2 by HAM3
• Linoleum installation at EX, expected to continue through this week
• Fire alarm drill
• Elli, Jax, Alberto and Bram working at EY at different times of the day, working on one arm test
• Ken working on electrical at EX

It turns out that the Ring Heater itself can be used to measure it's temperature. The resistivity changes with temperature. We see the voltage change over the first hour when the heater is turned on: - this is due to an increase in temperature of the ring heater wire and a subsequent change in the resistivity of the nichrome winding.

I've estimated the temperature of the ring heaters over time using a nominal value of 0.00017 K^-1 for nichrome and the measured RH voltage from last week's test. You can see the results in the attached plot.

T0 = 1029555836 for Segment 1

T0 = 1029555847 for Segment 2

Voltage signals = H2:TCS-ETMY_RING_HTR_SEG1_V_MON_OUTPUT, H2:TCS-ETMY_RING_HTR_SEG2_V_MON_OUTPUT

Current signals = H2:TCS-ETMY_RING_HTR_SEG1_I_MON_OUTPUT, H2:TCS-ETMY_RING_HTR_SEG2_I_MON_OUTPUT

35W beam

We had trouble locking the FSS, and left it unlocked for several days. This was tracked down to the cable going to the FAST actuator and was replaced yesterday, and it's held lock since then, so it looks fixed. This is the reason for the drop in the crystal temperature.

CoreyG HughR

We had done some large horizontal moves of the ISI per IAS (Initial Alignment) on Aug 1.  So after that we wanted to check the elevation.  It was still pretty close: 0.9mm low at worse with a range of 0.4mm level.  The vertical was tweaked to desired elevation +-0.1mm: -252.9(LIGO Global--E1000403)+12.5(Global to local--T1100187)=-240.4mm.

To Do list for SEI at HAM2: Respond to IAS with HEPI moves.  Iterate Horizontal/Vertical adjustments.  When good, attach HEPI Actuators, recheck with IAS.
Meanwhile--fine tune ISI lock/unlock balance.  Test ISI in prep for SUS payload.  Unload dummy payload when testing complete.

General:
Last week, the ISI, SUS and HEPI models-screens were updated to receive the last features and to replace the EPICS connection between the SUS and SEI watchdogs by the reflective memory (BSC6). The dolphin connection (SUS-SEI) will be added on BSC8 next week. The safe snap shots were also updated.

Ramping functions:
Both isolation filters of the ISIs and HEPIs can now be ramped using a function launched from MEDM. A restart procedure is currently being written. The DCC # is E1200762.

ISI Control:
I have changed the compensation filters of the output filter bank of ISI-BSC6 and ISI-BSC8. The cut-off frequency of the compensation filters was lowered 2 weeks ago (losing 6 degrees of phase at 30Hz). By the time, the watchdogs were tripping when engaging the boost filters. The “Turn on” option of the boost filters was changed from “zero crossing” to “ramp” (10s). The current filters are the initial ones.

I have introduced the T240 in the stage 1 blend of the 2 ISIs. The isolation provided by stage 1 using the T240 in the super sensor is higher (factor 5-6 @ 2Hz) than with L4Cs in the blend. During a quiet period, several configurations were tested. I have attached some results of few measurements on ISI-BSC8:

The first plot ITMY_T240_Y_2012_08_14_aLOG.pdf shows the non calibrated ASD of the stage 1 velocity (measured by the T240) in the Y direction with the different configurations:
- Damping only
- L4C X-Y-Z blend at 250mHz; L4C RX-RY-RZ blend at 750mHz; No Isolation on stage 2
- T240 X-Y-Z blend at 250mHz; L4C RX-RY-RZ blend at 750mHz; No Isolation on stage 2
- T240 X-Y-Z blend at 100mHz; L4C RX-RY-RZ blend at 750mHz; No Isolation on stage 2

The second plot ITMY_GS13_Y_2012_08_14_aLOG.pdf shows the non calibrated ASD of the stage 2 velocity (measured by the GS13) in the Y direction with the different configuration:
- Damping only
- L4C X-Y-Z blend at 250mHz; L4C RX-RY-RZ blend at 750mHz; No Isolation on stage 2
- T240 X-Y-Z blend at 250mHz; L4C RX-RY-RZ blend at 750mHz; No Isolation on stage 2
- T240 X-Y-Z blend at 100mHz; L4C RX-RY-RZ blend at 750mHz; No Isolation on stage 2
- T240 X-Y-Z blend at 100mHz; L4C RX-RY-RZ blend at 750mHz; Isolation on stage 2 – 750mHz blend
- T240 X-Y-Z blend at 100mHz; L4C RX-RY-RZ blend at 750mHz; Isolation on stage 2 – 250mHz blend

Blend switcher for the ISI:
The blend switcher allows changing blend frequency and type (CPS-L4C blend or CPS-T240-L4C blend) on the fly. It's working well. However, the isolation filters still have to be ramped up with the CPS-'L4C in the blend since the T240s saturate in the ramping process due to the small initial DC offsets (with the reference position) of the platform.

HEPI:
The blend and isolation filters controlling the pringle modes were reintroduced. The transfer functions used for sensor correction are linked below:
- H2_HPI_ETMY_H2_HPI_ETMY_TF_STS2_To_L4C_2012_07_03_044933.fig
- H2_HPI_ETMY_H2_HPI_ETMY_TF_STS2_To_L4C_2012_07_03_044933.pdf

(Bram, Alberto, Daniel)

This morning we were investigating the odd PLL oscillations that prevented us from increasing the servo gain. We found a very narrow resonance around 287.56kHz with a Q>100. We saw this resonance before, but it seemed to have had a much lower Q. It is unclear why this resonance has become so much more pronounced in the past few days. Our 100kHz low pass filter was designed to take care of this, but is obviously not sufficient to suppress a high Q resonance. Reducing the ugf to 6.5kHz avoids the instability, but will require that the cavity locking servo runs at a lower ugf too.

We then successfully locked the cavity. Looking at the I and Q signals it seemed that the RF phase was poorly adjusted. We first switched the delay line phase shifter to external, so we can use the medm screen to adjust the phase. Secondly, we minimized the Q signal by going from 135º (255 steps) to 85º (160 steps). We left the delay line in external mode. Meaning, it is important to restore the EPICS settings after a reboot.

While we were out there we also fixed the missing RF level readbacks from the second wavefront sensor demodulator board. They were connected to the wrong connector of the ASC demodulator concentrator.

The DAMP ON PR2 transfer function measurements were taken yesterday afternoon and this morning. Data has been exported to .txt files and the DTT .xml templates saved.

DTT .xml files and exported .txt files are saved and committed to the SUS SVN locally under:
'/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/PR2/SAGM1/Data/'

DTT .xml file names used:
2012-08-14_1810_H1SUSPR2_M1_WhiteNoise_L_0p1to50Hz.xml
2012-08-14_1810_H1SUSPR2_M1_WhiteNoise_T_0p1to50Hz.xml
2012-08-14_1810_H1SUSPR2_M1_WhiteNoise_V_0p1to50Hz.xml
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_R_0p1to50Hz.xml
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_P_0p1to50Hz.xml
2012-08-14_1810_H1SUSPR2_M1_WhiteNoise_Y_0p1to50Hz.xml

Exported .txt file names used:
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_L_0p1to50Hz.txt
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_T_0p1to50Hz.txt
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_V_0p1to50Hz.txt
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_R_0p1to50Hz.txt
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_P_0p1to50Hz.txt
2012-08-15_1438_H1SUSPR2_M1_WhiteNoise_Y_0p1to50Hz.txt

PDFs of plots:
'/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/PR2/SAGM1/Results/'

Saved as:
2012-08-15_1438_H1SUSPR2_M1_*_TF*.pdf

Data committed.

I am running these TFs - please do not touch the PR2.  It should only take me an hour, I'll alog when I am done.

The latest H1 SUS PR2 transfer function measurements were taken on the M1 stage this afternoon. Data has been exported to .txt files and the DTT .xml templates saved.  Plots of the data with the model trace are attached.  Plots with previous measurements to follow.

DTT .xml files and exported .txt files are saved and committed to the SUS SVN locally under:
'/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/PR2/SAGM1/Data/'

DTT .xml file names used:
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_L_0p1to50Hz.xml
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_T_0p1to50Hz.xml
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_V_0p1to50Hz.xml
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_R_0p1to50Hz.xml
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_P_0p1to50Hz.xml
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_Y_0p1to50Hz.xml

Exported .txt file names used:
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_L_0p1to50Hz.txt
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_T_0p1to50Hz.txt
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_V_0p1to50Hz.txt
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_R_0p1to50Hz.txt
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_P_0p1to50Hz.txt
2012-08-14_1720_H1SUSPR2_M1_WhiteNoise_Y_0p1to50Hz.txt

PDFs of plots:
'/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/PR2/SAGM1/Results/'

Saved as:
2012-08-14_1720_H1SUSPR2_M1_*_TF*.pdf

The attached is the latest transfer function measurements taken on H1 SUS PR2 SAGM1 stage.  The data was taken 07-29-2012 and is plotted with the predicted model and a previous measurement from the metal build in the Staging Building.  The pdfs are committed to the SUS SVN under:
'~/sus/trunk/HSTS/Common/Data/allhstss_2012-07-29_*'

Data committed in:
'~/sus/trunk/HSTS/H1/PR2/SAGM1/Data/2012-07-29_H1SUSPR2_M1_WhiteNoise_*DoF*_0p1to50Hz.txt'

DTT templates used had the same name but with an "xml" extension.