Kiwamu, Dave O, Paul, Elli

We used the digital cameras looking at the test masses to compare scattering from ITMx and ITMy and from ETMx and ETMy.  From our measurements, it appears that ETMy scatters more light than ETMx.  The two ITMS scatter comparable ammounts of light.

We took photos of each of the test masses with the IR locked in each arm and the green beam misaligned.  Examples of the kind of scattering we saw are attached in scatteringPRofileExamples.jpg.

We then estimated the total light scattered onto each camera.

-The camera aperature was opened to maximum for each camera.  The exposure time was chosen to be the same for both ITMs and both ETMS, and the exposure was chosen so very few (<5) pixels were saturated.  When we did this, we noticed two particularly bright smears on ETMy.  We had to reduce the ETM exposure level right down before these two spots stopped saturating the camera.

-We also took background images of each optic with no IR or green beam in the arms at the same exposure level.  We also subtracted the noise floor from the images.  The images with background and noise removed are attached in backgroundAndNoiseRemoved.jpg.

-Finally the pixel value for each image was summed over the entire image to give a value proportional to the ammount of light scattered onto the camera.  These pixel sums are: (the matlab code for calculating these is attached.)

At a super low exposure time of 200microseconds, we detected no light scattered off of ETMx, but we can still see an appreciable ammount of light comming off of ETMY.

The ITMs were imaged at 10000microseconds exposure time, and the amount of scatter we see is much more comparable than for the ETMs.

Alexa, Evan

We want to perform some ringdown measurements of the arms (particularly the Y arm) in order to corroborate our other loss measurements. We intend to use the technique described by Isogai et al., which has already been carried out at LLO (see, e.g., LLO#13748, LLO#11727).

In preparation, we've done the following work:

• We have placed a PDA255 on ISCT6, in front of ASAIR_B (since it is currently unused). The dc bandwidth of ASAIR_B is supposed to be 100 kHz, which is fine for observing the power decay (which probably has a ~2 ms time constant), but may not be fine for observing the initial power spike.
• In front of the PDA255 there is a 28 mm lens in order to provide a smaller spot size for the PD.
• Cyrus has paired the LVEA scope (TDS3038, I think) with a wireless router. With Chris's script for grabbing data from the scope, we should be able to take ringdown measurements comfortably from the control room.

Tomorrow we'll try to take some data and analyze it.

It appears that Conlog had stopped running at around 15:16. The following error was logged:

Dec  9 15:16:54 h1conlog2 conlog: ../conlog.cpp: 301: process_cac_messages: MySQL Exception: Error: Out of range value for column 'value' at row 1: Error code: 1264: SQLState: 22003: Exiting.
Dec  9 15:16:55 h1conlog2 conlog: ../conlog.cpp: 331: process_cas: Exception: boost: mutex lock failed in pthread_mutex_lock: Invalid argument Exiting.

I've restarted it for now.

J. Warner, K. Venkateswara

As detailed in LHO alog 15511 and SEI alog 645, the BSC chambers would benefit from LLO's "0.43 Hz only" sensor correction filters for X and Y

Jim and Rich had installed the filters previously. I turned them on at ETMX along X and Y. The gains were set to ensure clear subtraction on the CPS channel relative to the ground by a factor of ~10 near 0.43 Hz as seen in the attached plots.

Dan H, Sudarshan K,

The ISS second loop automation is implemented in the IMC guardian. This included a slightly modified script from alog 15164.

We added ISS_ON as a requestable state and CLOSE_ISS and OPEN_ISS as intermediate state to move  in and out of  it. The sticky issue is setting the REF_SIGNAL voltage to get the OUTPUT to zero. We do that  by looking at the sum of the in-loop-pd signal. This takes several seconds and occasionally will sets the initial ref signal little off from the optimal value because of the in-loop-pd transient.  We need to find a better way of doing this for our future iterations.

There are some failure modes in the CLOSE_ISS mode which will trigger jump transitition to OPEN_ISS. This can result in a never ending loop if the script keeps trying and failing to close the loop. In this case you can change the requested state to LOCKED and it will return to LOCKED when it fails the next time.

Had been modified to accommodate Rai W.'s needs for ionizer test

Had started this job yesterday -> Should run Corner Station purge air compressor with new booster pump before purge air is needed to confirm cooling is adequate

Installed dust monitor (Location #2) at BSC10 for the ETM-Y Vent. Filiberto and Manny worked cabling issues with the location #2 dust monitor dropping network connection. Will run the dust monitor for 24 hours and check its operation. 

Installed a dust monitor near the door at HAM-1(Location #1) for the vent of HAM-1 next week. Will monitor and establish a base line ahead of opening the chamber.   

Day's Activities

• 7:09 Cris/Karen cleaning LVEA
• EY Dust Monitor investigation (Filiberto, Jeff B)
• 8:55 Picking up cable from EY (Elli, & Dave O)
• 8/58 Alexa stopped a script she was running overnight (will post alog)
• 9:00-11:17 Karen cleaning at EY
• 9:01 Escorting Control Solutions person for tour of End Stations (Bubba, John W)
• 9:05 Cris at EX
• 9:08 Joe D testing eye showers in LVEA
• 9:34 Parts search Chris S.
• 9:59 - 2:30 H2 laser enclosure measurements on OFI (Gerardo, Dave O, Elli)
• 10:11 Restarting server which authenticates ligo.org accounts; should only take a few minutes (Cyrus)
• 10:16-11:56 PEM cabling & output analog cameras down for a little (Filiberto, Aaron, Manny)
• 10:41 EY Pcal Camera work (Sudarshan)
• 10:43 Begin reboots of End Station SUS/ISC & DAQ (Dave, Daniel)
• 10:50-11:19 Parts search in LVEA & then EX to cover Pcal camera (Travis)
• 11:37 PEM microphones in LVEA (Sudarshan)
• noon DAQ Restart & Guardian reboot (Dave)
• 12:45 Praxair delivery to CP2
• 2:36 TCS parts search (Andres)
• 2:43-2:51 Checking on cameras (Corey)
• 2:44 Restore pressure regulators for upcoming vent at EY (Kyle)

EY Dust Monitors both appear to go INVALID

h1guardian0 restart: DB and PT

We rebooted the h1guardian0 machine for testing. As last week, the guardian nodes restarted automatically with no problems but conlog died. We were closely watching the conlog MEDM screen and saw all the numbers increment wildly for a second and then the IOC died. Patrick noticed that in both cases, it was one of the new guardian USRMSG channels which logged an exception (these are the 100 byte array PVs). During this morning's conlog channel reconfiguration we removed these channels from conlog, and will test with another guardian reboot next Tuesday.

End Station SUS and ISC changes: DS and DB

Daniel installed new SUS and ISC models in both end stations. The DAQ was restarted to support these changes (new INI files for ISC).

Beckhoff Code Changes: DS and DB

Daniel installed new Beckhoff code in all three locations. The following INI files were changed: h1ecatc1plc1, h1ecatx1plc[1-3], h1ecaty1plc[1-3]. The DAQ was restarted.

Code With Local Mods:

the attached files show front end and guardian files with local modifications which require commits to svn.

Partially loaded filter modules: DB

The load-all-coefficients button was pressed for the following models: h1suspr3, h1sussr3, h1susomc, h1susitmx, h1lsc, h1sushtts

Files without controls group access: DB

Shared files on the /opt/rtcds/userapps, /opt/rtcds/lho/h1/target and /ligo/svncommon which were not writable by controls group were modified to be so.

INI and Foton Checks: DB

Running DAQ INI files and filter module foton files were passed through inicheck and foton. Reports attached. Reminder we have DAQ channels with mixed case in their names.

DMT DAQ: DB

Verified all DMT channels are in the DAQ and there is no duplication

Regular weekly updates and also removed Guardian user message channels as they are suspected as the cause of errors upon Guardian restarts.

I've updated the TLS certificates on cdsldap0, which is the CDS translucent LDAP proxy that provides ligo.org authenticated logins to the control room.  It took longer than expected, because it didn't like the format of the new key file and slapd would die with a "main: TLS init def ctx failed: -207" message.  Running the key file through 'certtool --infile key.pem -k' and using the resulting base64 encoding made it work, apparently gnutls is picky in what it will use for a key, even though it's own tool can read the key as is...

These instruments have just been sitting on thefloor with no insulation so Krishna Jim and I got them under Trillium igloos.  We had trouble with the internal Cable routine and may revisit to improve that.

Directly following the restart of Guardian, Conlog exited with the following error:

Dec  9 10:34:34 h1conlog2 conlog: ../ecm_cac.cpp: 515: event_handler: pv name: H1:GRD-SUS_OMC_USERMSG: args.status is not ECA_NORMAL: ca_message: No reasonable data conversion between client and server types: Exiting.
Dec  9 10:34:34 h1conlog2 conlog: ../conlog.cpp: 331: process_cas: Exception: boost: mutex lock failed in pthread_mutex_lock: Invalid argument Exiting.

This is the same thing that was seen last Tuesday, but with a different channel name (H1:GRD-SUS_OMC_USERMSG instead of H1:GRD-HPI_ETMY_USERMSG).

It has been restarted.

We are in the process of preparing a cleaning of ETMY. Even so, it is not conclusive, ETMY has a clear problem as indicated by the green ring type absorption pattern which is thought to be due to first contact material left behind. At least 2 of the bright spots are extended and do not look like single point defects. A vent in EY is planned to start Monday next week. The opening of HAM1 has been delayed to next week as well to allow us to keep working with the Y-arm this week. Since we do not want to "bake" contaminants to the TMs, we decided to postpone any locking attempts and instead concentrate on a couple of task which previously had second priority.

Here is the list of commissioning task for the next 7-14 days:

Y-arm loss investigation:

1. Make another wider scan on ETMY.
2. Make a similar scan on ETMX.
3. Try to understand the ITMY scan.
4. Ring down measurements.
5. Mode matching measurements.

Seismic:

1. Investigate why the LHO performance is still lagging behind the LLO one.

Length team:

1. Characterize PRMI power build-ups.
2. RFAM measurements (including a EOM bias voltage).
3. Measurement of the Schnupp asymmetry using the aux. laser on IOT2R.
4. A good set of RFAM length measurements.
5. Commission updated tidal compensation/length relief strategy.

Alignment team:

1. DMRI WFS: add SRM alignment loops.
2. Make EY green WFS work again.
3. Add triggers to the auto-centering system, so it can be engaged automatically.
4. Add a "bleed" feature to the auto-centering system, so it automatically resets when it looses the beam.
5. Commission an arm alignment controls topology which can be used for initial alignment.
6. Integrate green WFS into initial alignment.
7. Revise initial alignment scheme.
8. Investigate the temperature dependence of the TM orientation (T step in EX with cavity locked).

Miscellaneous:

1. Fine tune Michelson contrast defect using ITMY TCS/CO2 laser.
2. Set up the HWS to check the thermal lens.
3. Investigate the long-term alignment stability of the mode cleaner ISS.
4. Add an "ISS engaged" state to the IMC guardian.

RF:

1. Revive the EOM driver.
2. Make an assessment of RF cross talk into the IMC AOM.
3. Investigate EMI radiation by the VCOs and the fixed frequency OCXO.

Measurement running overnight

Dan and I have left an MC measurement going overnight. It should only last about 6 hrs, so should be complete by the morning. In case I am not in early enough to turn everything off and it is interfering with people, do the following:

1. Turn off the input of MC common mode board Exc A (I will clear the awggui's that are running; as long as this excitation input is off they won't be doing anything)

2. Set the three LSC lockin oscillators Amp to 0

3. caput H1:ISC-EXTRA_C_REFL_AO_1  =  0

4. Disable MOD on IFR; this step is not really necessary and I can do it once I am in.

Evan, Krishna, Alexa, Dan, Kiwamu,

At some point in this evening, we noticed that the IMC kept dropping its lock for some unknown reason. It turned out that the HAM2 ISI sensor correction was amplifying seismic at 0.3-ish Hz which resulted in a large drive in MC2 to keep it locked. So we turned the sensor correction off for now. This fixed the issue.

Even though the MC2 coil DACs were not saturating, somehow the motion was big enough to unlock the IMC. It is still unclear why it could unlock. Anyway, after turning off the sensor correction, the amont of drive in MC2 suspension reduced by a factor of 5 or so and IMC became able to stay locked. With the sensor correction on, the MC length was moving approximately +/- 5 um according to IMC_X displacement monitors. We don't know what changed in the HAM2 ISI sensor correction as it has been running fine for a while recently. Only thing we immidiately noticed was that the seismic freq-limited RMSs were pretty high in 0.1-0.3 Hz and 0.03-0.1 Hz bands in this evening. The attached is a time series of the IMC_X signals when we did a simple test of turning on and off the sensor correction in the HAM2 ISI. Since we were a bit rough for turning on and off the correction, it gave a transient when switcing it, but one can still see that when the correction was running, the IMC_X signal increased by roughly a factor of 5.

S. Dwyer, J. Warner, H. Radkins, K. Venkateswara

We did a quick test of sensor correction (SC) along X direction to Stage 1 ISI, previously described in 15146. This attempts to use the ground seismometers located near the test mass chambers in feed-forward like manner to reduce the cavity motion. Sheila and Jim aligned and locked the X-arm using the green laser and data was recorded with SC OFF and ON.

The first pdf shows the signals with SC OFF and the second shows them with SC ON. The signals shown first are the Stage 1 T240s (inertial sensors), the CPSs (positions sensors) and the X arm control signal. The inertial sensors indicate a significant reduction in motion of Stage 1 on both ETMX and ITMX between 50-500 mHz. The microseismic motion is suppressed by factor of ~4. Yet, surprisingly, the X-arm control signal looks almost similar. The oplevs shown on pages 3, 4 indicate that the angular motion of the optics was unchanged so perhaps it might be limiting the control signal.
 

J. Kissel, A. Pele

Ran transfer functions over the weekend, to assess if the SUS is free after first contact removal and closing doors. While the top stages look great, this is the first time I've been exposed to a factor of two missing between model and measurement for the lower stages. While we don't expect the model to account for the dynamics of the reaction chain (which is why we see a whole bunch of "extra" features in the main-chain dynamics), we don't expect an overall gain mismatch. Arnaud informs me that this is true of every QUAD except one stage of one (including L1 SUS ITMY). 

No reason to pull doors off, but we should figure out where this discrepancy lies. And also , we should develop a model of the lower stage dynamics which include both chains.