I got some alignment work done, but not as much as I would have liked.

I had just finished aligning the Xarm to green, although it's flashing and not locking.  Flashes up to 0.8, so it seems fine, but the PLL is complaining about not enough beatnote signal.  I don't actually know where that PD is, so I can't check it's alignment. 

The IR flashes also looked good, so I was getting ready to misalign the ITMY, use BS to get the beam onto AS_C, and then work on aligning ISCT6.  However, the PSL decided that it had had enough, and decided to turn off.  So.  I'll come back to this Monday after the laser crew is done with their activities for the day.

Side note:  The Yarm green is complaining about beckhoff communications errors, if someone more knowledgeable than me could have a look at that Monday as well.

The PSL has turned itself off. 

I spoke with Jason, and it looks like perhaps the chiller decided to turn off, which triggered the laser interlock to shut off the PSL.  The crystal chiller reservoir looked fine, although there was water on the floor and a cap had popped off (apparently this happens as part of the chiller turn-off?). 

The H1:PSL-OSC_BOXHUM channel has been exponentially increasing over the last ~20 hours from 28 to 35, which is consistent with the air conditioners being turned off around that time. Jason tells me that when the AC isn't drying things out, the box humidity usually sits in the 35-45 range, so since it's just now getting to 35, it seems like there is NOT a water leak. 

Jason logged in remotely, and agrees that things should be safe to leave as-is until he and Peter come in on Monday morning. 

Attached is a plot of the power measured at the base of the IO periscope as a function
of the requested angle in the MEDM screen.

    The following angles may be of interest:
minimum power -25 degrees
maximum power  -70 degrees and 20 degrees

    Measurements were performed with the Ophir power meter, using 3 second averages.

    The requested angle was consistent with the scale etched on the rotation stage.
To check that the half waveplate was not slipping within its mount, angular requests
moving the waveplate from one end to the other were made and the power measurements
were consistent with previous measured values.  So there was no experimental evidence
of the waveplate slipping within its mount.




Jason, Peter

After experiencing some problems locking the frequency stabilisation servo yesterday.
The plan was to improve the mode matching to the pre-modecleaner.  After which the
frequency stabilisation servo still did not lock.  The cause was traced to the locking
photodiode not having it's power cord plugged in.  The power cord, located underneath
PSL Rack 1, must have been disturbed.  Once plugged in again, the frequency stabilisation
servo locked.

The power incident to the pre-modecleaner was increased to ~150 W.  The measured throughput
of the pre-modecleaner was ~124 W, with the power stabilisation off.  With the power
stabilisation the throughput was ~117 W.  The power stabilisation suffers from occasional
glitches.  It is not known where the glitches come from, they may well come from either
the pre-modecleaner or the oscillator.

The output power of the pre-modecleaner was attenuated before the IO electro-optic
modulator to 60W.  The maximum power available at the base of the IO periscope is
~60 W.  The so-called "volume" control was tested, and a maximum power of 56 W was
measured when the rotation stage MEDM screen was used to request a power or angle.  We
found that both the requested angle and requested power are consistent with the
rotation stage scale and the power meter.

A more detailed report will be submitted later.




Jason, Peter

All time in UTC

Log:

23:24 Lase CO2 laser to make power measurement.

00:12 CO2 laser turned off. The rotation stages' angles are set such that they output lowest power the next time the lasers are lased. The "Go to minimum" function doesn't seem to work very well with CO2X (it gave 0.9 W output) so I manually set it to go to 40 deg (0.015 W output).

00:41 Resetting WDs.

01:18 Peter and Jason came out. We have the light!

02:45 Keita transitioned LVEA to LASER HAZARD

03:01 Jenne to help Keita at ISCT6

Possible issue with in-vac alignment. Shop closed early.

We also realigned all the main optics.

We're able to see the beam on ISCT6 camera but in-vac alignment is somewhat questionable. We'll align the table once at least the green transmission is seen in ISCT1.

The table fan was turned on and then off.

Accelerometer on HAM6 door is not connected.

Miriam, Jenne

*SUMMARY*

We check the L1 and L2 FASTIMON channels introduced in Feb 2016 and the L3 LVESDAMON at the times of blip glitches (found on data from Feb 11 and Feb 13). This investigation suggests that the actuation electronics are not the cause of blip glitches, but their origin must be in the interferometer.

*DETAILS*

We investigate 5 different times: 1139199176.774658, 1139240197.712158, 1139246246.086670, 1139400338.701172, 1139412012.846924

The channels we look into are of the kind H1:SUS-(E/I)TM(X/Y)_L(1/2)_FASTIMON_(UL/UR/LL/LR)_OUT_DQ and H1:SUS-ETM(X/Y)_L3_LVESDAMON_(UL/UR/LL/LR)_OUT_DQ.
These channels show the actuation on the mirrors. 

We plot the whitened data from the H1:OMC_DCPD_A_OUT_DQ as well as the whitened data from the channels mentioned above. The vertical lines show the times listed above. In the attachment we show only the channels that showed something significant. When the blip glitches are loud (higher SNR), it can be observed in the plots that the actuation starts pushing on the mirrors only after the DCPD has seen the blip glitch. 
Therefore, the blip glitch must have originated in the interferometer and not in the actuation electronics.

Layout is O1 version.  Current O2 version has a second high power beam dump, in preparation for up to 50W input power.

DCC# is D1300357-v1, O1 version

The two new BRS status Guardian nodes have been added to the Guardian Overview. The purpose of these nodes is to give the condition of the BRS in the node's state (ie. READY, DAMPER_ON, FAULT). The nodes seemed to have ran well over night so I added them and we'll see what they do over the weekend.

I attached a screenshot of the important code for BRS X. I would still like to make a way to check if the software has crashed since this was a big issue previously, but there are plans to change the computer soon anyway.

The code is simpler for the BRS Y, and the node only really looks at the DAMPCTRLMON channel. If this channel is above 8000 then it is in good shape, if around 3000 then the damper is on, and if less then it is in some type of fault.

1/2 open LLCV bypass valve, and the exhaust bypass valve fully open.

Flow was noted after 1 minute and 11 seconds, closed LLCV valve, and 2 minutes later the exhaust bypass valve was closed.

I isolated the aux pump cart yesterday afternoon to let the HAM6 annulus ion pump run on its own.

Today at 21:30 utc the aux pump cart and accesories were shut down.  All hardware is decoupled from the chamber.

Extended, routed and terminated CDS signal cable for HAM5 annulus ion pump controller.

With the need for heat in the LVEA low we took Heater 5 offline to convert it over to the variac system.  To protect the components we have limited the unit to 440V AC.
Must have a bad heater on C phase as the current draw was too low.  I have to talk to the vendor about adjusting the span on the controller.  We now max out at 14ma instead of 20ma.

4ma off <.5A
6ma 2.41 A 90V
8ma 8.6 A 175V
10ma 19.1A 265V
12ma 33.5A 355V
14ma 50.1 A 439V

No issues unlocking and no issues reisolating the platforms.  I'll run range of motion & linearity tests; possibly transfer function too, just because.

Late entry from yesterday. We discovered that h1pemcs's channel H1:PEM-CS_ADC_4_26_16K_OUT_DQ was railed at +20V. It was determined that this channel in the AA chassis was bad. I demoted this channel in the model back to 2048Hz and promoted H1:PEM-CS_ADC_4_28_16K_OUT_DQ to 16384Hz so Robert continues to have two 16kHz channels for his microphone work.