The PSL was shut down today to allow for work in and behind the racks (to avoid accidental power disconnections). That work has been completed and the PSL has been brought back up.

The ILS would not lock the lasers, but once the phase of the ILS LO was set back to 42 degrees (from 242 degrees) it locked up immediately. Had similar issues with the PMC, but by adjusting the phase of the PMC LO to minimize the error signal it was able to lock. Phase was set to 247 degrees (90+157). REF value was set to 1.02V and gain is at 13dB.

PMC and ISS are locked. FSS is still refusing to lock, it has been turned off for now. LRA and watchdogs are enabled.

Additionally the PMC reflected power level channel does not seem to be connected, and the ante-room camera did not come back up. I've unplugged it for now.

Mark B. & Szymon S.

On Thursday June 7, 2012 we tried testing the L2 (penultimate mass) OSEMs after Jeff G. reported a problem with the upper right OSEM.

We saved a DTT template under: 
/ligo/svncommon/SusSVN/sus/trunk/QUAD/H2/ETMY/SAGL2/ETMY_L2_OSEM_testing_template

Shaking the top mass M0 in the longitudinal direction [H2:SUS-ETMY_M0_TEST_L_EXC] and monitoring the OSEM readback signals [H2:SUS-ETMY_L2_OSEMINF_UR_OUTMON] in DataViewer, we found that the UR OSEM was only responding with 1/5 of the amplitude as the other three OSEMs on that stage.

Setting up a 0.43 Hz (at around the first pendulum mode) sinusoidal drive with about 50 counts of amplitude in the reaction chain top mass [H2:SUS-ETMY_R0_TEST_L_EXC], we saw that there was no cross coupling between the main and reaction chains which indicates that they weren't rubbing together.

We then took a passive measurement of the L2 OSEMs, by looking at the power spectra of the channels:

H2:SUS-ETMY_L2_OSEMINF_UL_OUTMON
H2:SUS-ETMY_L2_OSEMINF_UR_OUTMON
H2:SUS-ETMY_L2_OSEMINF_LL_OUTMON
H2:SUS-ETMY_L2_OSEMINF_LR_OUTMON

In the attached plot we noticed that the UR OSEM on L2 did not have a magnitude consistent with the other three OSEMs around the 0.99 Hz mode.  We also picked up a transverse mode around 1.03 Hz from the UR, LR, and UL OSEM sensors - something that should not be present in these OSEMs, which are ideally only longitudinal sensors.  These features lead us to suspect that the stage L2 UR OSEM is misaligned, despite the painstaking efforts of members of the suspension team to get it right.

At this time, we don't think this problem merits going into the chamber to diagnose because of the delay that would be introduced from pumping.

Air drill brushing was completed early this afternoon and then the crew worked on hand-brushing. A total of five drills were used in this chamber:  four general purpose drills plus the dedicated brush for fins and rings.

I checked and documented the wipes that have been hanging in a flow-bench in the OSB Optics lab. The "last wipes" were taken in BSC2 on 25 May 2012 and have been exposed to air for ~15 days. There is no visible change in coloring. Please see pix attached.

ENDY pumpdown.

After 3 days. The glitch at 11:15 UTC (4:15 am local) is likely the gauge behavior.

Kyle and Gerardo are spraying helium today.

[Stuart A, Jeff B, Mark B, Jeff G]

Initial M1-M1 damped and un-damped transfer functions have already been taken for the PR3 (HLTS), see LHO aLOG entry 2649. Recently, magnets and AOSEMs have also been added to the lower stages (M2 and M3) to complete the full metal suspension, see LHO aLOG entry 2953.

As part of Phase 1b testing, these transfer functions can be compared with the model as well as TFs obtained from LLO's PR3 Phase 1b results. Also, since BOSEM and AOSEM sensors are available at all stages, power spectra can now be be taken.

Pre-flight checks have been carried out:-
- Confirmed watchdogs are configured to within accepted limits (see LHO aLog entry 2576).
- Confirmed M1 BOSEM INPUT FILTERS, gains and offsets (as per LHO aLog entry 2645).
- Configured M2 and M3 AOSEM INPUT FILTERS, gains and offsets:-

M2-UL s/n = 448, open-light = 18318.0, off-set =  -9159.0, gain = 1.638 
M2-LL s/n = 601, open-light = 20793.0, off-set = -10396.5, gain = 1.443 
M2-UR s/n = 336, open-light = 19426.0, off-set =  -9713.0, gain = 1.544
M2-LR s/n = 413, open-light = 18210.0, off-set =  -9105.0, gain = 1.647  

M3-UL s/n = 489, open-light = 17727.0, off-set =  -8863.5, gain = 1.692 
M3-LL s/n = 269, open-light = 23463.0, off-set = -11731.5, gain = 1.279
M3-UR s/n = 461, open-light = 25154.0, off-set = -12577.0, gain = 1.193
M3-LR s/n = 287, open-light = 17820.0, off-set =  -8910.0, gain = 1.684

- Configured COIL OUTPUT filter gains and signs, as specified in T1200015-v1. However, the sign has to be switched from - to + for the "side" BOSEM, since it has been relocated to the opposite side of the structure (as requested by SYS).

Firstly, I conducted some quick low-res M1-M1 TF's on all dofs in DTT (not recorded), just to confirm that no earthquake stops, blade stops or OSEM flags were rubbing since the last TF's were taken. The TFs obtained for Phase 1b testing of PR3 have now been compared with those obtained at previous phases of testing (allhltss_2012_06_07_AllHLTS_ALL_ZOOMED_TFs.pdf). 

Plot Key:-
Blue trace = Model
Orange trace = LLO PR3 Phase 1b at test-stand with damping OFF
Black trace = LHO PR3 Phase 1b at test-stand with damping OFF
Pink trace = LHO PR3 Phase 1b at test-stand with damping ON

Prior to taking power spectra data, it was necessary to enable the following DQ channels, so that data could later be extracted from the frames:-

X1:SUS-HXTS_M2_OSEMINF_LL_OUT_DQ
X1:SUS-HXTS_M2_OSEMINF_LR_OUT_DQ
X1:SUS-HXTS_M2_OSEMINF_UL_OUT_DQ
X1:SUS-HXTS_M2_OSEMINF_UR_OUT_DQ

X1:SUS-HXTS_M2_WIT_L_DQ
X1:SUS-HXTS_M2_WIT_P_DQ
X1:SUS-HXTS_M2_WIT_Y_DQ

X1:SUS-HXTS_M3_OSEMINF_LL_OUT_DQ
X1:SUS-HXTS_M3_OSEMINF_LR_OUT_DQ
X1:SUS-HXTS_M3_OSEMINF_UL_OUT_DQ
X1:SUS-HXTS_M3_OSEMINF_UR_OUT_DQ     

X1:SUS-HXTS_M3_OSEMWIT_L_DQ
X1:SUS-HXTS_M3_OSEMWIT_P_DQ
X1:SUS-HXTS_M3_OSEMWIT_Y_DQ

To ensure the above channels were available it was necessary to restart the framebuilder. 

Power spectra have been taken (using the Matlab script "plothlts_spectra.m") with damping loops both ON and OFF for each stage (2012-06-08_1800_X1SUSPR3_M*_ALL_Spectra.pdf)

Power spectra data, again with both damping ON and OFF have been taken, which compare X1 PR3 (at LHO) and X2 PR3 (at LLO) on the triple test-stands (allhltss_2012-06-08_ALL_Spectra_Don.pdf and allhltss_2012-06-08_ALL_Spectra_Doff.pdf).  

In addition, power spectra for specific degrees of freedom (L, P and Y) can be more conveniently compared across multiple stages (M1, M2 and M3) of the same suspension in the final plots found below (allhltss_2012-06-08_X1SUSPR3_M1M2M3_Spectra_ALL_Don.pdf).

A BURT snapshot has been taken of the latest PR3 functioning environment "20120606_x1sushxts_PR3.snap" and stored in the following directory:-
"/opt/rtcds3/tst/x1/cds_user_apps/trunk/sus/x1/burtfiles".

All data, plots and scripts have been committed to the SUS svn as of this entry.

This should now be sufficient to complete Phase 1b testing of the PR3 suspension.

Finally, thanks also to Jim Batch for being able to restart the trippleteststand when I was unable to log-in remotely earlier today.

Attached are plots of dust counts > .5 microns.

Just saw that it was down and restarted it. Not sure what caused it, maybe network error?

Thanks Dale for the photos.  And the Apollo crew too-Randy MarkD Zack Caleb & Ed.

We did have some positioning issues of the A-Frames--shortcoming of the procedure and my oversight.  This caused us to back track briefly while we adjusted.  But we made numerous measurements that will allow us to set up the Fixtures closer next time and not get into this position.  Other issues discovered related to long bolts with the Spacer installs and interferences with the Shipping Braces.  But all things with which we can and will deal.
The Chamber top 16.5" flange was replaced and is torqued (metal to metal.)
The ISI remains to be torqued to the Support Tubes and of course lots of cabling to attach etc etc.  Four to go!

Entries by others will provide additional details about the installation.  Clearance over HEPI units was close.  View today's photo collection in ResourceSpace.

Pressure is moving slowly. Today the annulus system was evacuated with no noticeable impact. Tomorrow Gerardo will spray helium on new conflat joints.

For reference BSC8 reached 1e-6 torr in ~2 days with the same size turbo. ENDY has the additional load of the iLIGO stack.

The following are some loose items in the PSL installation, largely in infrastructure:

• Access control communication between H1 LAE and H1 diode room
• Replace chiller hoses in the chiller room
• Check anteroom airflow and overpressure
• iMacs and mac minis need to go to CDS network. Ubuntu needs to be installed on them as well
• Dust monitors without internal pump need to be installed
• Alarms need to be created
• CDS POE network switch needs to be set up
• Install external TV
• Get environmental signals into DAQ
• Set up final configuration power/rf supplies (cables need to be run too)

After MichaelR's struggles with the PMC locking yesterday, I worked on things a bit today.

The laser tripped again, apparently due to a temporary loss of AC power.

The AC power distribution is a MESS.  Hopefully this will all be replaced soon.

Rodney wants to run the low-loss RF cables to the PSL rack tomorrow and I think the only reasonable thing to do is just shut down the PSL during that work. - the chances of not shutting down the laser again would be negligible, I think.

After today's outage, the HPO would not lock.  Eventually, I checked the phase that minimizes the error signal.  It was about 152 deg.  Thus 62 deg. looked better than the 42 deg. used earlier for the injection locking.  However, 242 deg. (62+180) was what was required to get the HPO locking again.

The Noise Eater servo was oscillating at around 800 kHz, so I disabled it at the NPRO power supply.

PMC locked right away.  I suspect that the HPO was the problem yesterday, or maybe the relaxation oscillation.

FSS is now proving a bit finicky; MichaelR is working on it from the control room.

The two Tektronix function generators appear to be properly locked to eachother - PMC/ISS unit displays "Ext Clock Ref" with input from the ILS/EOM unit.  However, it seems that we are having phase issues.

Hopefully switching to the aLIGO RF sources and delay units will be more stable.

We will leave the laser running overnight with at least the PMC locking.  The LRA has been enabled, as have the watchdogs.

We will shut down for Rodney's work in the morning.

Brushing began today with the collar, upper, and mid-sections completed. The worrisome area at C/U-11/12 brushed off nicely (although we will still FTIR it). There are twelve drills ready for use should they be needed.

In our investigation to prevent the new H1 front ends from killing the PSL data, we moved all the H1 systems over to the new timing master today. Previously only the new SUS and SEI front ends were clocked from the new master (via the fanout in the H1 EE room), the h1psl and the DAQ were being driven from the old H2 master. All systems were moved over this morning and restarted, which resulted in some downtime of the PSL. Unfortunately we can still regularly corrupt the PSL DAQ data when starting the other front ends, so the investigation continues. We also worked on configuring the H1 Dolphin network to be identical to the one at LLO.

The IOP model ran for 24 hours after the one-stop fiber optic cable was replaced Tue. At noon today I started the user models (SUS FMY and FMX). So far, so good, but a bit early to declare victory.

We have all the lifting gear attached to the ISI and the Transport Rails positioned at the Chamber.  The Spacers are attached to the Support Tubes.  We will fly the ISI from the Diagonal to the South Bay in the morning and I expect to have the chamber all covered (I-Beams removed) by lunch.

We didn't have any trouble positioning/rolling the A-Frames.  We sealed up the chamber as best as possible with the rails in place--See photos:
DevilDog Ed shows how easy it is to move the A-frames (001).  Zack connects the back end of the Rail being steadied by Caleb to the Frame (005) followed by Ed securing the rail to the Middle Frame (006).  The Chamber is now ready for the ISI to be nested in between the rails before the Front Frame is connected up (008).  Meanwhile, MarkD confirms we are using Bumax bolts on the lifting pads while Scott double checks their location followed by precise torquing (004).  Randy ran the crew & crane.

Thanks-H