[Rodica, Kiwamu, Dick, Michael R., Keita, Paul]

Last night and today we finally managed to get what looked like a good measurement of the IMC pole response. Here is a brief description of the measurement setup:

Swept sine signal applied directly from the SRS785 to the AOM driver box inside the PSL. Frequency range was 1kHz to 100kHz, signal amplitude was 400mV pkpk. 1000 intergration cycles, and 101.56ms integration time. Measurement was a transfer function from the DCPD on the PSL installed recently (PDA55) to the DCPD on the IOT2L table (DET100A). ~200mW injected to modecleaner.

The PDA55 on the PSL table didn't give us an observable signal from the amplitude modulation previously when we tried on Wednesday. Rodica checked the Thorlabs recommendation for best linear performance, which states that the maximum intensity should be less than 10mW/cm^2. Even with a very low beam power we may have been exceeding this value due to the very small beam size. The PD was therefore moved to have a larger incident beam size.

We were struggling to get a decent signal on the SRS785 until Kiwamu suggested reducing the light power reaching the PDs to less than 1V. Once we brought the power down to less than 600mV, we were able to see a decent signals on the SRS785 and began taking TFs. 

The first attached transfer function is directly from the PSL PD to the IOT2L PD. In the event that the response of both PDs is linear, this should just give the cavity response. However, we noticed that the phase dropped below -90deg on the TF, indicating the presence of another pole - likely that of one of the PDs. We therefore took a TF from the PSL PD to the IOT2L PD, with the IOT2L PD repositioned in the IMC REFL path and the cavity misaligned (as Giacomo did previously). This TF is the second attached plot, and shows the pole of the IOT2L PD. Finally, we then divided the first transfer function by the second to eliminate the different PD response, leaving us just with the cavity response. This transfer function, along with a fit, is shown in the third attached plot.

For now, I just fitted the phase of the pole measurement, which gave the result 8812.36 Hz for the cavity pole. I'll try a complex data fitting routine soon and post the result.

Following the install of OneStop cards in the IO Chassis for h1seib2 and h1susauxb123 I made the first release of the IOP models for these front ends.

h1iopseib2 and h1iopsusauxb123 models were started this morning.

I went through all the H1 IOP models this afternoon to clean them up, bring the comments up to date and add the SVN keywords $HeadURL$ and $Id$.

I then added the propset for these keywords and submitted to svn.

I'll schedule a rebuild and restart of all IOP models at some future maintenance time.

h1susauxh34 received a new OneStop card but is still showing a power supply problem.

I also cleaned up the LHO CDS Overview medm screen to remove systems we are not immediately installing (e.g. SUS ITMX) to remove misleading white blocks.

• IO team worked on MC cavity pole measurements
• Apollo worked on the transition of install infrastructure from BSC 1 to BSC 2 and drilled for cable tray supports along the Y beam manifold.
• Eric and others worked on HEPI actuators at BSC 3
• Michael R and Joe D inhabited the H2 PSL enclosure for much of the day, prepping for PCal assembly
• Richard -- EX access controls
• Hugo, Mark and Vincent working on SEI and SUS in the afternoon.
• No surprising alarms
• No work permits signed by ops today
• Second-Saturday tour tomorrow, RIck and Gregorio
• Note other entries about today's activities below
• Cyrus restored joystick control of the roof and LVEA cams; this disables the Web controls

Dust monitor 4  in the beam splitter test stand clean room was of interest today because of drilling for cable trays along the Y beam manifold.  Signals from this monitor were quiet throughout the drilling, with only occasional 3um counts of 10 or 20.  There have been several higher count episodes (100-200) over the last 1.5 hr while someone has been working on the suspension.

That is half of the L4Cs have been leveled.  We got the East side done today and will work on the West side corners Monday.  The HEPI remains unlocked--mind the signs please.

Attached are plots of dust counts > .3 microns and > .5 microns in particles per cubic foot requested from 5 PM Feb. 6 to 5 PM Feb 7. Also attached are plots of the modes to show when they were running/acquiring data.

Data was taken from h1nds1.
1440 seconds worth of data was unavailable on this server
1440.0 minutes of trend displayed

Betsy (sadly logged in as Robert)

Today, we finished adjusting the roll, pitch, and z DOFs of the glass PRM.  The center of the optic is sitting at 158.75mm above the table surface (if it had the 19.1mm spacer under it).  The nominal is 158.8 +/- 1mm.

Travis adjusted the top stage BOSEMs to center in x,y,z and Mark is on deck to run TFs.

We;ll refit the lower stage OSEMs next week.

Found BSC5 dome annulus is leaking badly -> Will spray new CF joints next week

Vincent told me that H1 TMSY was ringing up when the damping was on. BIO was working.

Eventually I found that I had to turn down the damping gain of all rotational modes by half, plus turn off ELF10 filters in the coil outputs, to get going stably. Since there is zero reason to go aggressive under the air, I'll leave them like that for now.

H1:SUS-TMSY_M1_DAMP_R_GAIN is -10 instead of -20.

H1:SUS-TMSY_M1_DAMP_P_GAIN is -5 instead of -10.

H1:SUS-TMSY_M1_DAMP_Y_GAIN is -5 instead of -10.

All ELF10 filters are disabled instead of enabled.

My guess is that somebody decided to go aggressive under the vacuum a long time ago, and now, in the air, OSEM positions are different and that makes coupling between DOFs different, causing oscillations.

Viton pads are usually set under the balancing masses of the HAM-ISIs in order to damp resonances at high frequencies (above 100Hz).

The SEI team would like to asses the improvements that the Viton Pads help achieving. To do so, we decided to have viton pads under the balancing masses of the ISIs of LLO's IMC, and to try without those pads here at LHO.

Transfer functions were measured ovenight on LHO HAM3-ISI. We compared those transfer functions with the ones measured at LLO under an equivalent state:

• ISI is in vacuum
• MC2/PR2 are installed and damped
• TMDs are intalled on the ISI
• HEPI is locked

Comparative plots are attached.

I acknowledged the following alarms Friday morning:

• HVE-LY:CP1_LT100 (minor alarm, value=83.9 at 23:36:25 on 2/7)
• H0:PEM-LVEA_DSTl_3
• H1:PSL-ENV_DIODERM_TEMP_DEGF major (exceeding 70F between 1:00 and 2:00 on 2/8)
• H1CDS_IOP_SUS_WATCHDOG ITMY OSEM6 (minor, value=500, 18:11:29 on 2/7)

All of these cleared when acknowledged except the IOP which remains yellow.

The Apollo crew removed the ISI from BSC 10 and placed it on the north side of the termination slab, wraped, bagged and sealed. We chose to stand down on the ICC for now, instead we relocated the clean rooms that were over HAM 4 and BSC 1 and began disassembly of the E module and work platform around BSC 1 to be relocated to BSC 2.

At approx 08:10 this morning the network to the EX FMCS system and the wall camera was disrupted. Upon investigation we found that the ethernet cable in the VEA rack was disconnected. This cable had an extender and a 6 feet additional ethernet cable before it plugged into the Foundry switch. The connection at the extender was disconnected. We found that the extender was not needed any more and plugged the long haul cable directly into the switch.

Dan from LDAS worked on the h1ldasgw0 system to investigate why h1fw0 has become unstable since last Wednesday 30 Jan with apparent disk write slow downs. He upgraded the firmware, we then restarted the h1fw0 writer. Jim has made h1nds1 the default nds because of this problem so the shutdown had minimal impact.

After h1fw0 was restarted we restarted the DAQ due to an 0x2000 status on h1hpiham1. It appears that the model change earlier made channel number changes and a change in DQ channels (perhaps a common model was changed recently).

The magnetized PR3 optic was loaded into the custom ABO today for a 6 hr. ~34 degC air bake.

Yesterday, we installed the PRM optic in the suspension.  Today, we adjusted roll and suspended it.  It has a bit of a pitch which we will need to work out tomorrow - the top mass is ~level and the optic is ~level, but the middle mass is pitched.  So, it's either the top mass blades, or middle mass weight configuration inducing pitch.  WIll confer with others and make adjustments tomorrow.  Preliminary height measurements do not indicate any major height problems.  Final numbers/tols will come later after tweeked.

I really didn't get to any L4C leveling but unlocking is the first step so I did get started on this long pending task.
Please be mindful of the signs and avoid the blue Crossbeams.

Activities for today:
- Pole cavity measurement, PSL room, Michael R., Rodica M. and Paul F.
- Jim B., One-stop card addition, see his aLOG.
- Eric A., working around WBSC02, no cranning needed.
- Hugh, Cable relief at WHAM02.
- Ski, working fixing X-Mid intrument air.
- Kiwamu, ALS path work, PSL area.
- Praxair, LN2 delivery CP1.
- Kyle work at the input tube large ion pumps.
- Hugh, work at HAM01, HEPI is unlocked now.
- Dave and Jim, visited X-End troubleshooting FMCS/camera communication issues.

The communication problem with X end FMCS has been fixed