TITLE: 05/15 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Various maintenance activities around site, prep for HAM6 doors off tomorrow, and PEM PSL work.
LOG: See attached

As per Chandra's request, I reconfigured the cell phone alarm system to no longer alarm on the channel:

H0:CDS-ROC_VAC_MY_CP3_TE202A_DISCHARGE_TEMP_DEGC_1HOUR_R

DAQ restart:

for new:

H0EDCU_VAC.ini (h0vaclx.ini)

h1ecat[c,x,y]1plc2.ini

H1EDCU_GRD.ini

Slow controls SDF were restarted for h1sysecat[c,x,y]1plc2sdf. Any new channels were ACCEPTED+MONITORED

This morning, CoreyG, Marek, DanB and I went to EX and installed the last 2 baffle panels on the PCALX periscope. Marek & Corey stayed outside the chamber, used the top gun on the panels and installed fasteners in. Dan and I waited inside, and put screw caps on while they were working outside. No real issues. All hardware has been installed, including screw caps and barrel baffle fastener swap (for new coated hardware, this had been done a couple weeks ago). Corey took some photos, hopefully he'll post.

   CS: Pump temps and vacuum pressure are within specs. No adjustments made.
   EY: Pump temps within spec. Made slight increase in vacuum pressure.
   EX: Pump temps are high due to scroll compressor running. Opened up bypass to add more cooling.

   Closing FAMIS ticket #7525  

TravisS, RickS

Yesterday afternoon, we transitioned Xend to Laser Hazard, energized the Pcal laser, checked the beam centering on the Pcal Receiver Module power sensor, then transitioned back to Laser Safe.

The beams are well-centered on the power sensor aperture (see attached photo), indicating that the beams are still where we want them on the ETM surface.

After the unsuccessful search for the AS_C signal today (see 41962 and comments), I wanted to get some of the DRMI alignment better.  This will help us be sure that, when we go into HAM6, we're working with a roughly okay beam. 

I started with a place that I knew from last week that I could lock PRX.  While locked in PRX, I dithered PRM in length and rotated the RF phase of REFL_9 and REFL_45 until the PRCL signal was all in the I-phase.  This took REFL 45 from an old value of -13 deg to a new value of -53 deg.  This took REFL 9 from an old value of -90 deg to a new value of -30 deg.  Net -40 deg for RF45, and +60 deg for RF9.

The only mirror (out of PR2, PR3, BS, ITMX) whose alignment was different from the single-bounce alignment was PR2.  So, I noted my PRX-locked value for PR2, and went back to the single-bounce value.  I walked PR2 toward my PRX slider values, while moving SR2 and SR3 to keep beam on AS_A and AS_B.  In the end I was able to lock PRX while still seeing beam at the AS port.  I then misaligned the PRM and aligned the SRM, giving me an SRX configuration.  I did a very rough alignment of SRM until I saw SRX fringes.  I then misaligned SRM, and ITMX, and realigned ITMY.  I moved ITMY around until I saw beam on the AS WFS again (since we don't have an AS camera yet).  Once I realigned ITMX, I had some weak MICH fringes.  I tweaked up the alignment of ITMY, and now have pretty good MICH fringes. 

Depending on what we decide in the morning meeting, I may work more on locking and aligning DRMI, although the beam we have should be good enough to see signal on AS_C, certainly within picomotor range.  Since we're seeing beam at AS_AIR, we can't actually be all that far off......

I installed a microphone and accelerometer in the PSL to help study the vibrations sources.

After evicting a tiny snake out of the X-End VEA floor, it just didn't want to go, I went to check on the purge air skid.  This system was having issues keeping up with the demand.
After shutting off 4 out of the 5 compressors found that we had 3 relief valves stuck open, wasting lots of air.
All 3 bad relief valves were replaced and the system appears to be healthier now, after 30 minutes of the skid running on all compressors the dew point was measured at -18.2 ^oC.

CP4 pressure on 450 l/s turbo pump is 2.5e-9 Torr. Will take RGA scans tomorrow. Bake enclosure will be removed tomorrow.

Recording pressures and RGA scans weekly with HV1600-10 activated at EY. H2 reduction is most significant change.

PT-428 = 1.62e-7 Torr (NEG housing hot cathode gauge)

PT-410 = 1.21e-7 Torr (BSC 10 main volume cold cathode gauge)

In an effort to complete work at the vault and vault power room prior to the dry season we have been pushing hard to get the readbacks for the Seismic and LEMI channels in the vault operational.  Many issues impede this work, including but not limited to bugs, mice and their biproducts, bees, goat heads, snakes, dirt, weather, spotty communication to the control room, etc...  Currently the seismic reset resides inside of a bees nest.

The FIBOX is a system that can read in an audio signal (seismic and magnetic LEMI signals) and transmit them via multi mode fiber over long distances.  Our system has three Seismic channels, X, Y, and Z, and two LEMI channels X and Y.

Over the past week we have tried resetting the FIBOX's, replacing them with freshly calibrated units, we carried everything back to the lab and tested it, carried everything to MID X and tested the throughput.  After testing the FIBOX's at MID X with a local fiber, I can report that all of the channels are working as designed in this controlled environment.  The ADC inputs also work when a signal is injected into them.

When the FIBOX's are placed in the vault the seismic channels look bad, I assume it is because we cannot reset the seismic system (reset located in bees nest).  The LEMI signals also look bad.  Next step will be to read the signals directly with an oscilloscope and inject signals directly with a function generator out in the vault.

Everything is reconnected in the vault as of 3:00pm PDT.

Alexei, TVo

Ran a measurement OMC mismatch from of single-bounce beam (off of ITMX) as a function of SR3 heater temperature.

The power to the SR3 heater was gradually ramped from 0 W to 5 W (corresponding to a temperature range of 25 C to 70 C) over the course of several hours to account for the SR3 time constant (about 15 minutes according to G1501373)

The OMC was scanned by applying a sawtooth ramp voltage to PZT2_EXC with a period of 20 seconds and amplitude of [0,120] counts.
There were also some OMC alignment loops that were closed during the scan (AS_A, and AS_B?) (I'm sure TVo will correct me if I'm wrong).

The mismatch was computed by measuring the ratio of the second order peak to the zeroth order peak. The mismatch data was taken by an OMC scan analyzer tool that I've been developing, which tries to track the zerorth and second order peaks
in time by essentially plotting the PZT2_EXC channel against the AS_DCPD channel. I will upload the tool on gitlab and pypi hopefully sometime soon when it can be used without needing me to watch over it.

The final plot ( m_vs_temp_1_2.png ) is the summary of the measurement, which is a combination of two sets taken about an hour apart. The mean mismatch managed to drop by about a 1% over a 40 C change, with a fluctuation of about 1% for any given temperature. I'm not really sure why the mismatch data is so noisy (I confirmed that the tool was correctly tracking the heights of the peaks). I was also unsure what temperature load the SR3 heater could sustain ( G1501373 says that either 10 W (emitted?) or 87 C is the max).

I will investigate the single-bounce models of the IFO to see if the mismatch change is what we expect.

Thomas, Dan Brown

This morning we wheeled out the SRM heater to the north side of HAM5. The CO2 laser cannot be switched on currently until the SOP is complete, the controller for the CO2 is on Thomas' desk. The goal today was to try and align the table to the two steering mirrors and the holes in the SRM baffle. We managed to center on the ZnSe viewport and the first steering mirror. Changing pitch and yaw there we could trace the beam around the edge of the first baffle hole, we were unable to do the same on the output baffle hole. When we believed we were centered correctly the alignment beam could be clearly seen on the baffle on the HR side of the SRM, we're currently unsure whether that should be the case or not. We also do not have a good view of the beam dump from the north side which makes trying to align into it difficult. We still have some alignment work to do here before we are ready.

The north HAM5 door area is now sectioned off with screens between the squeezer table and the clean room, pictures of the area are attached. 

Daniel, Jenne, Fil, TVo

In preparation for this weekend's work to try to do an OMC Scan measurement while varying SR3 RoC, I decided to try to make sure our new alignment of the IMC could make it down to HAM6.  I was able to get light on AS_A_DC and AS_B_DC and close the centering loops but I noticed that AS_C had no light on it which is very odd.  

All the electronics were turned back on from our grounding loop searching from April 26-27 however, the attached trend shows that something dramatic happened to that QPD segments around Apr 27 2018 15:53:41 PDT which caused the individual segments to get much noisier and the sum to drop dramatically.  I'm pretty sure we were laser safe at the time so it wasn't like the a beam falling off the diode. So I thought this might be some sort of electronics problem like a disconnected cable in the midst of the madness, but everything in the rack to the chamber feed-through seemed to be connected properly, Fil and Daniel tested the in vacuum QPD chain from the outside with a multi-meter and confirmed that there is a connected diode in chamber.

So maybe we're just not seeing light? Again, this seems strange because we see light on both AS_A and AS_B.

In general, this won't deter our work this weekend but we might want to get this figured out before we open the doors early next week or put it on the task list for the chamber.  One method we haven't tried is looking for AS_AIR and seeing if that comes out of the viewport. Also, there is a picomotor we can actuate to steer the beam onto AS_C, but I'm holding off on this unless we know what is going on.

The two attached plots show before and after adding the final HEPI Y to RZ Cross Coupling factor.

This was first looked in alog 40106, 40117, & 40150 for ETMX.  I want to look at ETMX again as that was before I looked at the geometric consideration I posted earlier in 41955.

I feel pretty good about the solution here though now.

The optical lever out put during the HEPI length stroke is the sum of actual optic yaw plus the expected apparent yaw due to the OpLev Length to Yaw Cross Coupling: OLOutput = Actual + Expected.

So I want to minimize the Actual = Output - Expected.  Assume in this case the Actual is all caused by the HEPI Cross Coupling.  See the 40106 alog for the conversions and such to get the units, and the amplitudes of the OpLev Cross Coupling factors are from E1200836.  The signs of these corrections are subject to geometric analysis.

Anyway, with a CC factor for HEPI Y to RZ of 0.0065 in H1:HPI-ETMY_IPSALIGN_3_2 of the IPS Alignment Matrix, the residual is pretty much zero'd out as seen in the 2nd plot although I might be able to tweak it a little bit more.

This length drive on the ETMY HEPI is 0.8mm so a huge drive wrt anything we'd ever need to drive but why not get rid of it.