Derek Davis, Laurel White, Miriam Cabero

Following up a study done in O1 (see alog 28534) connecting internal humidity rates to an increase in the number of blips glitches, we repeated this analysis for O2. A plot of the blip glitch rate (based on Gravity Spy classifications) and relative humidity inside the CS mass storage room is attached.

The highest blip rates for the run in weeks 2-7 did correspond with a time of extremely low internal humidity, adding support to the previous theory that these trends are related. However, periods of similarly low humidity rates past week 7 did not correlate with elevated blip rates. Further follow up of how blip glitches during each of these low humidity periods (as was done in the previous study) may also help understand what is driving these large increases in blip glitch rate and whether efforts to better control the internal humidity are warranted.

Between ETMY closeout work at EY, Travis and I continue to rebuild the ETMX suspension at EY.

We're working towards installation of the new AERM07 mass into the reaction chain.  Last week we removed the ERM02 mass from the lower structure frame.  Yesterday we gutted the PenRe mass at the stage above this mass to rebuild it with heavier cans which compensate for the lighter AERM with the hole in the middle.  The 2 lowest masses of this reaction chain need to maintain their total before-rebuild weight, so the PenRe will need to be built to 64,303g:

* Weighed with scale during this rebuild

For my record keeping:

The output of the front end laser was transformed by a pair of nominal f=-50 mm and f = 80 mm lenses.
In positioning the lenses, the results measured with the Beamscan were not consistent with a simulation.
We already knew from a JAMMT simulation that the position of the lenses was very sensitive.  A fair
amount of time was spent adjusting the lenses and the measured result compared to the simulation.
Each time the measured result loosely followed the trend of the simulation but did not match it.

    The "mis-match" as it were was traced to a combination of a intermittent Beamscan and the application
settings for it.  A Beamscan with a smaller aperture was used to re-measure the results.  The lenses
were adjusted to produce a measured 273 um +/- 2 um beam diameter at approximately 73 mm from where the
70 W power amplifier will be located.  This better matches the input parameters given by neoLASE.

    The large aperture Beamscan should be sent for re-calibration and/or repair.

    This entry summarises work from the previous Friday and yesterday.



 Rick / Ed / Georgia / Jason / Peter

TVo, Terra

In anticipation of SR3 heater mode matching measurements, we've

1) made SR3 heater medm screen, under a new purple Active Wavefront Control button in TCS main screen

2) calibrated SR3 heater; values shown in SR3 heater calibration medm screen

1200 lbs. sitting on VEA floor 2' from BRS igloo.  

Longer "blow out" durations following activations further reduced counts.

Pumps will need to be activated just prior to exposure to VE if/when entering service.

Still need to remove equipment and clean up mess!  

Undid flange fasteners of newly installed gate valve at IP6 location and used the overhead crane to separate the valve a few inches from the port.  Visual inspection of vacuum seal weld looks normal.  Knife edge imprint in copper gasket indicates that gasket was "cocked".  Installed new gasket and torqued flange metal-to-metal, i.e., no gap around entire periphery.  Also, installed 1.5" valve and adapter to allow pump side of closed valve to be evacuated.  

J. Kissel

Inspired by Jim W. who had the idea to take OSEM basis transfer functions (see Jim's prototype measurements in LHO aLOG 41227) 
to help diagnose the lingering problems with the H1SUSOPO (see previous latest in LHO aLOG 41196), 
Stuart grabbed his own OSEM basis TFs of the healthy L1SUSOPO (see LLO aLOG 38455). 

Since Stuart's had a little bit better SNR, I imported his templates and re-drove the H1 SUS OPO in the OSEM basis.

The results (alloposs_2018-04-02_SUSOPOS_OSEMBasis_ALL_TFs.pdf) were indeed very helpful: it immediately identified H3 as having an incorrect actuation sign. I subsequently flipped the COILOUTF gain (as though it were, say, an incorrect magnet polarity), and this cleaned up the problematic Transverse and Yaw transfer functions perfectly. There's still an overall sign issue with Transverse, but correcting that with an opposite damping loop gain means that all DOFs now have functional damping.

The OSEM basis also reveals that V2 OSEM has a remaining problem of some very strange frequency response. That manifests only in the V, and P TFs (looking at E1700390, we see that R involves very little V2). I believe this strangeness is mechanical or electronic, because it has *changed* since when we first started measuring the H1 SUS OPO -- compare the change between the 2018-02-27 and 2018-03-29 results. 

We'll keep chasing these daemons tomorrow (and gather damping loops closed TFs), but I'm happy to say that we've finally made some progress!!

The new H1 data has been committed here:
OSEM Basis, prior to H3 sign flip:
    /ligo/svncommon/SusSVN/sus/trunk/OPOS/H1/OPO/SAGM1/Data/
        2018-04-02_2000_H1SUSOPO_M1_WhiteNoise_H1_0p01to50Hz.xml
        2018-04-02_2000_H1SUSOPO_M1_WhiteNoise_H2_0p01to50Hz.xml
        2018-04-02_2000_H1SUSOPO_M1_WhiteNoise_H3_0p01to50Hz.xml
        2018-04-02_2000_H1SUSOPO_M1_WhiteNoise_V1_0p01to50Hz.xml
        2018-04-02_2000_H1SUSOPO_M1_WhiteNoise_V2_0p01to50Hz.xml
        2018-04-02_2000_H1SUSOPO_M1_WhiteNoise_V3_0p01to50Hz.xml

Euler Basis, After H3 sign flip:
    /ligo/svncommon/SusSVN/sus/trunk/OPOS/H1/OPO/SAGM1/Data/
        2018-04-02_2157_H1SUSOPO_M1_WhiteNoise_L_0p02to50Hz.xml
        2018-04-02_2157_H1SUSOPO_M1_WhiteNoise_P_0p02to50Hz.xml
        2018-04-02_2157_H1SUSOPO_M1_WhiteNoise_R_0p02to50Hz.xml
        2018-04-02_2157_H1SUSOPO_M1_WhiteNoise_T_0p02to50Hz.xml
        2018-04-02_2157_H1SUSOPO_M1_WhiteNoise_V_0p02to50Hz.xml
        2018-04-02_2157_H1SUSOPO_M1_WhiteNoise_Y_0p02to50Hz.xml


The crude analysis script for loading in, processing and comparing the OSEM basis TFs is here:
    /ligo/svncommon/SusSVN/sus/trunk/OPOS/Common/MatlabTools
        plotOPOS_dtttfs_OSEMBasis.m

Dew point of XBM = -25.9C

Dew point of YBM = -52.6C

I'm calling XBM good after an inadvertent Friday night vent to atmosphere (from 45 Torr) with room air from flange/gate leaks on IP6 GV.

We will start roughing out both volumes tomorrow.

14:00 UTC Chris S. traveling both arms to assess tumbleweed blockage
14:30 UTC Chris S. finished. Both arms are clear for travel.
15:07 UTC Rick to PSL enclosure. Peter already there.
15:13 UTC Chandra to LVEA
15:30 UTC Nutsinee to HAM6, squeezer table
15:44 UTC APS on site (new access control system install)
16:00 UTC Morning meeting in control room
16:33 UTC Jeff B. starting transition of LVEA to laser safe
16:33 UTC Tyler and Mark to end Y to drop off IP valve
16:47 UTC Sheila to LVEA to help Jeff B. transition to laser safe
17:02 UTC Jeff B. done transitioning LVEA to laser safe
17:07 UTC Jeff B. to LVEA to remove old dust monitor air lines
17:11 UTC Gerardo to end Y to prep for IP/CHEV/GV install
17:15 UTC Kyle running crane
17:21 UTC Thomas taking Sebastian on tour of LVEA
17:24 UTC Mark, Tyler and Bubba inspecting HAM5 for door removal. Then Mark, Tyler to work on IP6.
17:30 UTC Travis and Betsy to end X to pick up bin then to end Y to work in chamber
17:32 UTC Sheila to optics lab
17:56 UTC Jeff K. done running measurements on HAM5 SUS
17:58 UTC Truck from Apollo through gate to see Bubba
18:03 UTC Jeff B. done in LVEA
18:19 UTC Karen to mid Y
18:20 UTC Sheila back
18:33 UTC Gerardo back
18:35 UTC Filiberto pulling cables over HAM5 and HAM6 (WP 7451)
18:55 UTC Karen leaving mid Y
Mark and Tyler back for lunch
19:09 UTC Visitor to meet Jenne through gate
19:26 UTC Filiberto out of LVEA
19:31 UTC Thomas to LVEA to retrieve equipment
19:46 UTC Jenne taking visitor on tour through LVEA
19:57 UTC Betsy and Travis back from end Y
20:11 UTC Marc to vault power room (WP 7452)
20:12 UTC Jenne and visitor out of LVEA
20:13 UTC Rick and Peter out of PSL enclosure
20:18 UTC Mark and Tyler to LVEA to install IP5
20:56 UTC Jeff B. to LVEA to run zero count and flow tests on dust monitors
21:23 UTC Terra and Thomas to electronics bay to calibrate SR3 ring heater
21:26 UTC Jeff B. done in LVEA. Moving to optics lab and diode room.
21:44 UTC Betsy and Travis to end X
21:55 UTC Jason to PSL enclosure
21:56 UTC Marc back from vault power room
22:00 UTC Gerardo to end Y to continue gate valve removal
22:04 UTC Jeff B. to end stations to test dust monitors
22:10 UTC Terra and Sebastian to LVEA to look for spare mirrors in cabinet by ITMX
22:26 UTC Mark and Tyler done at IP5. Dropping off gaskets at end Y then leaving site.
22:39 UTC Terra and Sebastian back
22:41 UTC Chandra to end Y
22:54 UTC Jeff B. done

   Zero count and flow test all dust monitors on site except in the PSL. Adjusted the flow on DM #5. All others were OK. 

   Added 50ml water to Crystal chiller. Diode Chiller water level is OK. 

   Crystal chiller filter is yellow and will be changed when the PSL changes are complete. Diode chiller filter is fine. 

This morning, Travis and I checked the ETMY suspension health and then made the pitch adjustments needed to compensate for the addition of the AMD devices to the front of the mass last week.  Like what was reported at LLO, roughly 200 uRad (up) of realignment was needed to recenter on the optical lever.  A few rounds of TFs showed that the suspension was still free of mechanical interferences, and OSEM speed dials looked good.

We then locked the test mass, swung the ACB back, attached the First Contact spray cone, and sprayed an application of the solution to the ETMY HR.  Per procedure, we removed the cone and reinforced the edge of the applied sheet with brush-on First Contact.  It now dries until tomorrow morning.  So, no oplev or pcal beams will be of use over night.

VE intends to work on the IP port near this chamber this afternoon.

J. Kissel, C. Vorvick

Cheryl and I grabbed base-line, top-to-top mass, health-check, transfer functions on all HAM5 suspensions (SR3, SRM, OFI, and ZM2) in prep to the corner-station vent this week, in which we'll install a picomotor on the OFI's SQZ path (ECR E1800070), and wider apeture eddy-current-damping brackets on ZM2 (D1800094). 

Delightfully, all suspensions show no problems what-so-ever, and results are comparable across similar instantiations of the given suspension type and across observatories. What a breath of fully functional fresh air (here's lookin at *you* HAM6 SQZ SUS...)!
 
Attached are all of the results. A double thanks to Cheryl for helping out!

The templates for the data plotted in this aLOG have been committed to the repo here:
    /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/
        2018-04-02_1703_H1SUSSR3_M1_WhiteNoise_L_0p01to50Hz.xml
        2018-04-02_1703_H1SUSSR3_M1_WhiteNoise_P_0p01to50Hz.xml
        2018-04-02_1703_H1SUSSR3_M1_WhiteNoise_R_0p01to50Hz.xml
        2018-04-02_1703_H1SUSSR3_M1_WhiteNoise_T_0p01to50Hz.xml
        2018-04-02_1703_H1SUSSR3_M1_WhiteNoise_V_0p01to50Hz.xml
        2018-04-02_1703_H1SUSSR3_M1_WhiteNoise_Y_0p01to50Hz.xml

    /ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/SRM/SAGM1/Data/
        2018-04-02_1636_H1SUSSRM_M1_WhiteNoise_L_0p01to50Hz.xml
        2018-04-02_1636_H1SUSSRM_M1_WhiteNoise_P_0p01to50Hz.xml
        2018-04-02_1636_H1SUSSRM_M1_WhiteNoise_R_0p01to50Hz.xml
        2018-04-02_1636_H1SUSSRM_M1_WhiteNoise_T_0p01to50Hz.xml
        2018-04-02_1636_H1SUSSRM_M1_WhiteNoise_V_0p01to50Hz.xml
        2018-04-02_1636_H1SUSSRM_M1_WhiteNoise_Y_0p01to50Hz.xml

    /ligo/svncommon/SusSVN/sus/trunk/OFIS/H1/OFI/SAGM1/Data/
        2018-04-02_1642_H1SUSOFI_M1_WhiteNoise_L_0p01to50Hz.xml
        2018-04-02_1642_H1SUSOFI_M1_WhiteNoise_T_0p01to50Hz.xml
        2018-04-02_1642_H1SUSOFI_M1_WhiteNoise_Y_0p01to50Hz.xml

    /ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/ZM2/SAGM1/Data/
        2018-04-02_1641_H1SUSZM2_M1_WhiteNoise_L_0p01to50Hz.xml
        2018-04-02_1641_H1SUSZM2_M1_WhiteNoise_P_0p01to50Hz.xml
        2018-04-02_1641_H1SUSZM2_M1_WhiteNoise_Y_0p01to50Hz.xml


All plotting analysis scripts (especially the plotall*_tfs.m) have been committed with the new measurements added to the list as well.

   WP #7440

   Removed the last of the house vacuum PVC piping from the LVEA and Mechanical Building. I also removed a 1/2" air line that was used for the old Lighthouse dust monitors. The Lighthouse monitors were shutdown several years ago. 

   This completes the house vacuum removal from End-Y and the Corner Station. Next up, as conditions allow, are End-X and both Mid-Stations.    

Platform installed
NEG pump commissioning almost done
Resume pumpdown of XBM today. YBM tomorrow.
Jeff K. running transfer functions on HAM5 SUS in morning
no Thursday 1PM meeting
Crane inspection postponed
New access control installation starting at warehouse
Prepping for HAM5 in chamber work (scheduled for Thursday)

   Transition LVEA to laser safe.

   (1). Closed and locked PSL beam light pipe
   (2). Locked both HAM6 tables
   (3). Turned off and removed key for both HAM6 lasers

    All other checks were OK

70W installation - ongoing

FAMIS 6097

Results attached.