Removed the 90/10 beam splitter in front of the RF LSC diode, and replaced it with a 50/50 beam splitter. Adjusted the gain to set the UGF to ~300 kHz. I tried to insert a ND filter to see if the 2.74 Hz peak disappears, but don't have a conclusive result yet.

Progress on the leak testing of the Vertex has been hampered due to the prevalence of "very" loose bolts on 80% of the flanges on the GNB provided MC spools.  After finding that 12 of the first 15 flanges tested were leaking badly I ceased spraying any additional helium and, instead, torqued the bolts on the flanges which were leaking.  This was very time consuming and was not "on the schedule" but did manage to demonstrate that the majority of leaking flanges could be made leak tight by doing this. 

I will propose that all of the GNB joints (leaking and not yet leaking) be torqued on Monday (Apollo help?) before continuing on with the helium leak testing. 

Aug. 3 OPS:

Start of the day: 
ISI tripped on ETMY - HEPI tripped on ITMY - Vincent looking into it, Bram emailed

Work going on:
craning arm to install on HAM3
Filiberto to EY to pull network cable
Karen to LVEA to clean
Patrick working in the NYN room
Patrick to EX to install dust monitor
Eric to HAM2 to install hardware on actuators
Kyle to EY - retrieving equipment from VEA
Alex to EY - inventory in TMS lab
Michael R. to EY TMS lab to verify tagged out lasers
Doug to HAM3 optics table to measure some threaded hole diameters
Karen and Chris to EY to clean
HAM3 has an ARM attached to it

[Jeff Bartlett and Andres Ramirez]

After replacing a broken magnet on the H1-MC3 intermediate mass, we ran Phase 1b transfer function. The results showed a rubbing issue at the side and left BOSEMs on the M1 Level, (2012-07-30_2100_X1SUSMC3_M1_ALL_TFs). While looking for something rubbing on the upper mass (which we did not find), discovered the T3 BOSEM showed no voltage, which was traced back to a loose connection at the D25 end of the cable. After reseating the cable, the SpeedDials values still did not look right. We reran the Open Light script for T3. The Open Light voltages were OK; the Offset and Gain values in MEDM were not correct. We reran the Open Light script for all the BOSEMs and adjusted the MEDM offsets and gains as necessary. 

We reran the transfer functions this morning (2012-08-03_0730_X1SUSMC3_M1_ALL_TFs), the results look much better. Requesting final approval for metal build of H1-MC3.    

[Elli and Bram]

After the OAT RefCav work, we relocked the PLL in EY. We had to tune the laser crystal temperature up to 42.27 degC (from 42.08 degC). We also teaked the waveplate, setting the beatnote power to -31dB.

I had a look at the refernce cavity today to see where we losing our gain. Initially I tweaked the alignment increasing it by approximately 10%, the 01-mode is now much dimmer on the monitor (I didn't do a scanning alignment, and tried to kept the cavity locked).

Also, I rotated the QWP just infront of the cavity to maximise the power on the RF LSC diode. In the beam just after the PBS, which taps the beam for the RF LSC diode, is a ~90/10 beam splitter (unlabelled), directing 90% of the beam to a CCD camera! Due to a lack of looking for a smaller splitting ratio beam splitter I left it inplace, so we now geting ~4 mW onto the RF LSC diode (of the 34.4 mW available in the return beam).

I dropped lock, so I could measure the power. Into the cavity is 46 mW, reflected is (out of the PBS) 34 mW. I measured the power incident on the transmitted diode but forgot to measure the total power transmitted! There is 4 mW on the RF LSC diode (reading 169 mV at the DC output). Once locked the power drops to 40 mV out of the DC output.

The UGF is 287 kHz, with the folowing Interface Settings

It runs with Common at 850 and Fast at 700 (UGF 315 kHz), but it becomes more sensitive to bumping and floor motion and starts to oscillate.

You can recover from the oscillation by reducing the Common gain to below 160, and bring it back up.

The relock of the RefCav is at a slightly different mode, asI tweaked the coarse tuning down wards to find the 00-mode. There is 210 micro Watts on the transmitted diode, reading ~828 mV (it has a gain setting of 20 dB).

Attached are plots of dust counts > .5 microns in particles per cubic foot. The dust monitor at location 8 in the LVEA (H0:PEM-LVEA_DST8_5) was put in the assembly prep area near HAM2 and HAM3.

Vincent finished installing the HEPI system. Because the ISC signals are now added into the HEPI feedback just after the compensation filters, the gain and sign have changed.

Now we have a gain of -2 (from +0.2). Also the units are not in nm anymore .... not a drama but makes thinking about limits a bit harder ...

I engaged the ISI isolation on ITM, but the ETM kept tripping so I left it in damping only (didn't further investigate).

Left the cavity locked for the night.

Kyle 

With the leak detector configuration as left yesterday, i.e. backing the Vertex MTP (100% of the turbo exhaust) the helium background had decreased from 1.3 x 10-8 torr*L/sec (as left yesterday) to 6.2 x 10-9 torr*L/sec today -> I vented the HAM5 and HAM6 annulus volume and decoupled the HAM5 aux. pump components leaving the pump port connection open to the room.  Then I let the HAM6 aux. cart diaphram backing pump pump air through the annulus, i.e. room air enters HAM5 pump port and routes through annulus volume and exits HAM6 pump port.  This was another attempt to expedite removal of any helium permeated in the annulus O-rings -> No help, too slow.  Next I calibrated our 2nd leak detector and swapped it in place of the initial leak detector -> No change.  It measured and behaved within 10% of the first.  This was done to rule out any instrument-specific inability the initial leak detector might have had in resolving helium ions from non-helium ions in the spec. tube (as the leak detector inlet pressure is relatively "high" baking the MTP).  This concludes my attempt to get the helium background to the nominal <2 x 10-9 torr*L/sec value.  

Moving on, I reconnected the initial leak detector and began testing CF joints on the output MC tube with a background of 6.2 x 10-9 torr*L/sec.  Two of the first three flanges I tested were 10-6 range leakers!! Ouch!!  Will have to continue tomorrow after this pumps away.  

Day's Activities:

Since there was not OAT activities during the day, this allowed for noisy activities in the LVEA/EY.

• HAM3 Survey work started off the morning
• Chris/Karen given ok for LVEA vacuuming
• Apollo crew were craning around ISC tables
• Vincent reconfiguring HEPI model for filter name changes
• Betsy turned on PR2 Damping
• Szymon did some ETMy SUS measurements earlier in the day
• Robert/Richard addressed a "noisy" transformer at EY
• SEI crew removed mass from HAM3 via forklift
• SUS crew staging to mount Installation Arm on HAM3
• Apollo busy down at EX (removing doors from BSC9, and staging for In-Chamber cleaning)
• YMCA Tour in the afternoon

This morning, the HEPI master model was updated, corrected and committed. The two HEPI models (BSC6 and BSC8) were recompiled, re-installed, restarted and restored. The safe burt snapshots were updated. Bram was able to lock the cavity with the new configuration.
Note that the Yaw offset is now introduced in the DC_BIAS and the ISCMON filter output signals are not going through the isolation filters.
Now, ISC signals can be read by the HEPI models using the reflective memory.

After the false start with damping measurements earlier, I went in and center the M2/M3 lower stage AOSEMs.  Unfortunately, we broke a magnet off of the temporary lowest mass during transport/rehanging, so LR AOSEM is not "seeing" anything.  We'll skip repairing it since we are about to move on to installing the real glass mass shortly.  I just turned damping on again now.

I would not normally put this here, but the stochastic log was unavailable.

To build our confidence in our understanding of instrumental H1-H2 correlations, we are attempting to identify the features in the H1-H2 coherence. I did this for part of the S5 data back during S5 (here), when I was able to trace many of the features to particular sets of fans, or to low frequency (0-15 Hz) BSC and HAM resonances in the bilinear coupling regions around 60 Hz peaks; the summary from 2006 is repeated here as Figure 1.

Here we check these earlier results with full-S5 data, making sure that the rest of the run is consistent with the earlier partial results by comparing the full-run and partial-run features in coherence and by comparing the full-run PEM spectra to the full-run coherence.

A comparison of Figure 1 and Figure 2 indicates that the clusters of peaks from certain fans and the bilinear coupling features are present in both the partial run and the full run, suggesting that the specific partial-run identifications could be extended to the full run.

We expect that peaks in the H1-H2 coherence are associated with peaks in important PEM channels (sensors at coupling sites or half way between H1 and H2 coupling sites). The full-run PEM spectra of important channels show peaks that correspond with the coherence features, except for the peak at 114 Hz. The 114 Hz peak in Figure 1 is the only peak labeled “uncertain” – there were fans in this frequency band, but the shape of the peak did not quite match the shape in the partial-run spectra. This is again true for the full-run spectra, so I am not confident that we understand the source of the 114 Hz peak in coherence.

We are currently looking into the possibility that a sudden change in coupling when I floated ISCT4 to reduce H1 H2 coupling might be responsible for the inconsistency in coherence and ASDs. 

I've turned the damping on for PR2 (chamberside, all metal HSTS) at 18:34 UTC / 11:32 PT, in order to take some damped spectra.  Motion on the optic looks steady as per the speed dials.

(not Bram)

Attached is a plot of the response of the laser crystal TEC when stepping 13mK up and then down at the slow input (assume -1K/V sensitivity). The response shows a spike by about +9mK and then -9mK (not clear how good either calibration is). The response time is roughly 5 sec which would indicate a ~30 mHz pole in the slow input of the laser.

B. Bland, J. Kissel

[[ These results are extremely belated, but I want to post them for posterity. ]]

After making adjustments to the static Roll of the optic, we've remeasured (as much as we remembered to of) H1 SUS MC2. Attached are the results.

Several things that these results indicate:

- The alleviation of the DC/static roll in the optic appears to have restored normalcy on the lowest L and T mode, i.e. they're no longer split in frequency. Huh!
- Now all degrees of freedom match well with the model, and other degrees of freedom.
- Spectra compared against in-chamber LLO suspensions indicate that excess noise seen at high-frequency is indeed most likely due to the noisy external environment on the optical tables. However, you'll notice that the noise has significantly reduced from when the SUS was in LHO staging building, so this confirms that the LHO assembly area is simply the noisiest environment where testing takes place, and it's not a problem fundamental to the suspension itself.


As of these results, H1 SUS MC2 has passed Phase 2b testing and is ready for install into HAM3.

I replaced the old ALS QPD output matrices (measured empirically by Elli and Thomas several weeks ago) with new ones based on Cartesian coordinates. I obtained these by ray-tracing on the ALS table. Then I measured the input matrices with a Matlab script (/svn/cdsutils/trunk/ALS).

Now the inputs of the IP_POS and IP_ANG filter modules should be calibrated in meters and radians.

These are the matrices:

INPIT =
  -0.001934944012837   0.000295830132597
  -0.000025683755141  -0.000141436038465
INYAW =
   0.001338191005451  -0.000236296533156
  -0.000010597031521   0.000352368394300

OUTPIT =OUTYAW=
   1.0e+07 *
  -0.746993867828206   2.240981603484618
   0.048486940975147  -0.800820822925440

The loops have UGF of about 10 Hz with these gains:

IP_POS_PIT= -8; IP_ANG_PIT=-8; IP_POS_YAW=-8; IP_ANF_YAW=-4

Attached are some spectra measured with the loops either open or closed.

The TMS table relative lateral stability seems to comply with the requirements (=100urad RMS). On the other hand the angular stability seems to be a bit worse than desired (=1urad RMS).

Long term stability (12+ hrs) still has to be evaluated.

Jeff K. , Thomas V.

Below are the calibration parameters for the H2 ITMY Optical Lever:
        Slope          Y-intercept
Pitch [ 580.41229822  -11.51774017]
Yaw  [ 689.70532274  -13.3345144 ]


And here are the calibration parameters for the H2 ETMY Optical Lever:
         Slope           Y-intercept 
Pitch [ 1666.80728788   -33.14694715]
Yaw  [ 1727.67131855     23.41350328]

Both sets of calibrations were attained via the same process of moving the QPD along a translation stage and measuring the output signal.  All four sets of slopes are in units of radian*meters.

OK now we have all the HEPI Actuators attached & released at the correct elevation and IAS has signed off on the position.

Elevation & level is 0.1mm below nominal of -250.5mm (wrt LIGO Global) with a +-0.1mm levelness.

Attached is my field notes of the final dial indicator readings and the level survey-enjoy.

Thanks to Mitchell & Jason