After the coarse IAS checks were finished this morning, Travis and I fully unlocked the ETMy QUAD which repositioned all of the masses into their pre-aligned posistions.  This also removed alot of extra locking bracket payload.  We then pulled all of the shield and optic cap payload and added the witness plate mount such that the total payload of the QUAD was within ~a lbs of being correct.  We then reclamped some of the masses lightly such that SEI can load masses around upstairs on top of the ISI in order to continue their work.

Kyle investigated.

Cyrus and Dave

around noon the /ligo file system became unavailable, causing the workstations to freeze up. We rebooted cdsfs0 and restored the file system. We are in the process of restarting the workstations to give them a clean NFS mount.

(Doug, Jason, Hugh, Betsy and CO)
First look at the ETMy in chamber measurements are very encouraging. 
Results:
Longitudinal was short by 0.5mm from absolute, tolerance is +/- 3.0mm,
Lateral position is 0.35mm to the south, +/- 1.00mm
Elevation position is high by 0.35mm, tolerance is +/- 1.0mm

Optic is set lightly on EQ stops, but for a first look to identify any need to move the ISI or SUS this is very reasonable results.

The arm cavity baffle was rough positioned to accommodate the line of sight from the spool and currently rests unattached on its installation table so use caution when working around it.

When fully pay loaded, cabled with the ETM suspended we will do the the fine alignments of the positions and optic angles

J. Kissel, for F. Matichard,

As mentioned in LHO aLOG 10397, Fabrice has installed a clean set of three blend filters on ETMX, ITMX, and BS. (I loaded ITMX filters this morning). Here're plots of the new blend filters for ST1 BSC-ISIs. 
"TCrappy" is exactly the same -- a version virtually identical to Ryan DeRosa's very-low-blend filters, 
"Start" are an improved "750mHz" that *actually* rolls off at high-frequency and does not include the T240s. 
"TStart" has the same displacement sensor / inertial sensor 750mHz crossover, but includes the T240s to get rid of L4C noise at low frequency.

The plan is to use "TCrappy" when possible, and "TStart" under high wind conditions.

7:00 pm PT EDIT:
I've now added the filters for both stages in all degrees of freedom for a BSC-ISI. I've done this using a newly committed version of
/ligo/svncommon/SeiSVN/seismic/Common/MatlabTools/plot_current_blends.m
Use it. All the time. When ever you install a new set of blends.

At 16:20:23 UTC

PSL-Status:
- Laser is on
- Output Power = 28.8 W
- Watchdog is good.
- System Status is good

PMC:
- Locked for 2 days 20 hours
- PowerRefl = 1.1  W
- PowerTran = 10.8 W

FSS:
- Locked for 1 h 12 m, relatively unstable yesterday afternoon
- Resonant Threshold = 0.7 Volts

ISS:
- Diffracted Power = 6.134%
- Last saturation event was 1h 14 mins ago.

Stefan, Kiwamu, Yuta  (Yes! I have ligo.org account now!)

Last night, MC could not acquire lock after the guardian update for HAM2 and HAM3. So, Evan and I turned off the MC WFS loop and tweeked MC2 alignment offsets to lock MC. After that, we turned on the MC WFS loop and it seemed OK. H1:IMC-MC2_TRANS_SUM_OUT was ~635 and H1:IMC-IM4_TRANS_SUM_OUT was ~1600.

However, the WFS loop for MC2 was actually not turned on because the switch in the filter bank H1:SUS-MC2_M1_LOCK_(P|Y) was turned off. This was actually the cause of MC2 misalignment. Also, MC input PZTs were turned off (H1:IMC-PZT_(PIT|YAW)). So, MC WFS went crazy over night.

So this morning, we relieved the feedback for MC2 (H1:IMC-MC2_PIT|YAW) to be zero. This MC WFS relief should be added to MC guardian.

Stefan, Kiwamu

We noticed that HEPI and ISI for ITMX and ITMY had been down. So we brought them back up. We didn't investigate why they had been down.

Also, engaging the ITMX ISI was rather difficult -- we had to take out the offsets in the T240 signals by manually changing the bias targets.

• ITMX
  • HEPI
    • Level 1
  • ISI
    • stage 1: level 3
    • stage 2: level 3
• ITMY
  • HEPI
    • Level 1
  • ISI
    • stage 1: level 3
    • stage 2: level 3

Help us, Arnaud.

The "save misalgined" command in IFO_OVERVIEW screen doesn't work for ITMX. I didn't check other suspensions. Please have a look when you have a chance.

Jason and I are ready for the lateral and longitudinal ETMy position measurements in the AM. We won't know whether we will need to tweak the ACB position for any line of sight issues until the first look. Thanks Betsy and Travis for setting the ACB for us (temporary setup). We will not release the optic suspension for the fine positioning until we are satisfied that no large moves are needed.

While in the chamber, we also connected the 5 SUS and 1 ring heater cables to the feedthru and confirmed signal throughput on the 5 sus.  We pulled the C3 covers from both of the ETMy and TMSy suspensions before installing the corner cube. 

Jason and Doug should have a clear shot of the corner cube (and probably the edges of the optic) through the ACB from the spool.  We await X,Y,Z measurements.

The readback channels for the corner station ring heaters seem to not have been working properly since last Friday.  I've attached a graph that shows that the ring heaters seem to have turned off at 02-21-2014 22:5:32 UTC.  Judging from the ALOG around that time, there were a lot of reboots going on in software, I'm not sure about hardware reboots.  However, Kiwamu says that the PRC power level is looking like the ring heaters are on just based off of the amount of loss he measured.  He also advised that since the system is working well, I should hold off on trying to power cycle the TCS chassis until a later time but at the first chance I get, we should try to resolve this issue.

The ITMX ring heater is also displaying similar weirdness, which is expected since they share the same chassis and PLC.

(Alexa, Jax, Stefan)

Alexa was trying to hunt down a missing gain factor for her model and instead found a busted COMM PLL board (serial number S1200564). The op-amp for the VCO compensation stage (U37) was blown. I recalled replacing the same op-amp on the DIFF PLL about a month ago, suggesting that there's something that makes this particular op-amp vulnerable. After discussing with Richard McCarthy, we opted to change resistor R96 from 0 to 2k ohms to protect the poor thing. Lab tests show that it's in good shape, and it'll be back to the ISC rack as soon as we're done with the ISC meeting.