Came into the Control Room at 8:45am(after the GW170817 press conferences)

Day's Activities:

• HAM4 work locking up the ISI & collect contamination samples (Hugh)
• 17:20- 17:47 Removing MC1 iris from HAM2 (Ed)
• 18:05 Staging parts for TCS work (TJ & John Richardson)
• 18:09 Recon HAM2 for baffling work (Jim)
• 20:17 HAM2 Baffle Checks (Jim & TJ)
• 20:43 PSL Crystal (top) Chiller topped off (Richard notified us of beeping, and Ed filled w/ 375mL)
• 21:36-23:00 OFI work at HAM5 (Gerardo, Peter)
• 22:30 Inside H1 PSL (Peter)

I parked this here for us to see and for a viable link from the wiki page.

Laser Status:
SysStat is good
Front End Power is 35.93W (should be around 30 W)
HPO Output Power is 154.0W
Front End Watch is GREEN
HPO Watch is GREEN

PMC:
It has been locked 2 days, 18 hr 41 minutes (should be days/weeks)
Reflected power = 23.4Watts
Transmitted power = 48.02Watts
PowerSum = 71.42Watts.

FSS:
It has been locked for 0 days 13 hr and 45 min (should be days/weeks)
TPD[V] = 2.632V (min 0.9V)

ISS:
The diffracted power is around 3.0% (should be 3-5%)
Last saturation event was 2 days 18 hours and 40 minutes ago (should be days/weeks)

Possible Issues:
PMC reflected power is high

Corner Station signals are a bit all over, but I reckon this is to be expected with open chambers.

End Stations holding steady.

I added 375mL of water to the Xtal chiller. It had been in alarm.

No issues.  ISI locked cleanly and 3 CC wafers collected for study.  ISI damping and other chores on deck.

I popped into HAM2 and made this adjustment. Below are before and after pictures.

Some time ago the transmission and polarisation rotation caused by the Faraday rotator was measured to be
98.8% and 15.6 degrees respectively.  At that time the TGG crystal was located towards one end of the
Faraday rotator - the "output" end. (see F1.jpg)

    After some effort in aligning the Faraday isolator we found that we could get good transmission but not
good isolation and vice versa.  Comparing the Faraday isolator with the unit installed in HAM5 revealed that
the TGG crystal is located in the middle of the magnet assembly.  Looking at the unit being worked on revealed
that the TGG crystal was loose within its holding cylinder.  Why and when it came loose is not obvious.  The
crystal was pushed more towards the centre of the Faraday rotator and the polarisation rotation angle was
re-measured.

    The new measurements suggest a transmission of 99.5% and a polarisation rotation angle of 46.1 degrees.
(see F2.jpg).  The angle plotted in both cases is the angle of rotation of a half waveplate.

    Anecdotally when the TGG crystal was pushed towards the centre, without any time spent optimising the
alignment we observed fairly good transmission and an isolation ratio of 30 dB.

    At present there is some confusion as to whether or not the TGG crystal is meant to be epoxied in place
or is held into place by what is rumoured to be a paramagnetic holder.  In either case the holding mechanism
failed.



  Koji / Gerardo / Peter

Will make comment to this entry when leaving.

J. Kissel

Took a set of Top to Top transfer functions for H1 SUS SRM this evening. Results look like the suspension remains free after Betsy & co re-engaged the OSEMs from having backed them off during the monolithic optic install. 

Data lives here (and has been exported to files of similar name):
    /ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/SRM/SAGM1/Data/
        2017-10-13_2122_H1SUSSRM_M1_WhiteNoise_L_0p01to50Hz.xml
        2017-10-13_2122_H1SUSSRM_M1_WhiteNoise_P_0p01to50Hz.xml
        2017-10-13_2122_H1SUSSRM_M1_WhiteNoise_R_0p01to50Hz.xml
        2017-10-13_2122_H1SUSSRM_M1_WhiteNoise_T_0p01to50Hz.xml
        2017-10-13_2122_H1SUSSRM_M1_WhiteNoise_V_0p01to50Hz.xml
        2017-10-13_2122_H1SUSSRM_M1_WhiteNoise_Y_0p01to50Hz.xml

Will post detailed graphical results with the usual comparison against previous measurements and the model on Monday. Attached is a sneak peak of the Pitch to Pitch TF, the DOF usually most sensitive to shenanigans.

The parts in question are D1101911 & D1101910.

HAM2: I've installed a QPD cable strain relief on IM4 trans. See first attachment.

HAM3: Done with MC2 trans and POPB, but not POPA.

For POPA, 1/4-20 screw wouldn't go in easily (I only tried for a minute or two) and I didn't bother to keep trying because I remember that this was a problem in the past for some of the QPDs (alog 19168 for TMSX).

One set of parts is left on the wire shelf on the work table in HAM2 cleanroom (top right of the wire shelf). If the 1/4-20 wouldn't cooperate, I would recommend to do the same solution as the above alog entry.

F. Clara, J. Kissel, R. McCarthy, G. Moreno

After 
    - sorting out confusion with drive electronics (thanks Fil and Richard!)
    - a few iterations of tuning transfer function amplitudes, 
    - realizing that the eddy current damping magnets may be interfering with / over damping the SUS, 
    - a tweak of a rubbing OSEM, and finally 
    - diagonalizing the longitudinal transfer function (i.e. actuating in Yaw to compensate for the SD OSEM's offset from the center of mass)
Gerardo and I have completed the first set of in-air, driven transfer functions with the recently installed OSEMs on the OFIS. 

Attached are the results, and the resonant frequencies are as follows:
    DOF          Freq (Hz)
     L         0.625 +/- 0.01
     T         0.625 +/- 0.01
     Y         1.039 +/- 0.01

This confirms that AOSEMs, driven with standard 16 bit, 20Vpp DAC, through a (LIGO) standard AI chassis, HAM-A coil driver and ISC/US-style satellite amplifier, pushing 3mm DIA x 6 mm LEN magnets is sufficient to drive the suspension. Further, the OSEM sensor has plenty enough signal to read out the position of the platform, so damping loops will be quite straight forward.

Excellent work design and assembly team!

Details
The data collection templates for the best, diagonalized transfer functions live in
    /ligo/svncommon/SusSVN/sus/trunk/OFIS/H1/OFI/SAGM1/Data/
        2017-10-13_2116_H1SUSOFI_M1_WhiteNoise_L_0p01to50Hz.xml
        2017-10-13_2116_H1SUSOFI_M1_WhiteNoise_T_0p01to50Hz.xml
        2017-10-13_2116_H1SUSOFI_M1_WhiteNoise_Y_0p01to50Hz.xml

Because the new SQZ electronics infrastructure is not yet in place, the drive chain is a temporary setup involving the digital drive chain of OM1 (hence the nonsensical denominator in the labels of the transfer functions), and several in-air cables, including a pin-flip ribbon cable (hence the poor coherence above 5 Hz).

Norna is suspicious of the OFIS's dynamical model put together by Mark Barton back in 2014, so hopefully this data can be used to solidify some degrees of freedom of the model.

I've created a new script that populates the new OFI's infrastructure with a diagonal sensor / actuator basis, which now lives in 
    /ligo/svncommon/SusSVN/sus/trunk/OFIS/Common/MatlabTools/
        make_susofis_projections.m
where the conventions are defined as in E1700352, T1200015, and G1701887. Note I'm also sticking with the SUS convention to have the OSEM2EUL and EUL2OSEM matrices be the *transpose* of each other, and not the inverse. Taking into account that the LF and RT OSEMs (for driving T and Y) are equidistant from the suspended center of mass by l_LR_to_COM = 0.111 [m], but the SD OSEM is offset from the center of mass by l_SD_to_COM = 0.056 [mm], means the drive matrix is 
  | L |    [     +r            +r             -1 ] | LF |
  | T |  = [     -0.5          -0.5            0 ] | RT |
  | V |    [    +0.5/l_LR      -0.5/l_LR       0 ] | SD |

where r = l_LR_to_COM / l_SD_to_COM, and I've abbreviated l_LR_to_COM as l_LR. Actually sticking in the numbers, and reporting as they must be in the CDS system, that's

OSEM2EUL = +1.9821   +1.9821   -1.0000         EUL2OSEM = +1.9821   -0.5000   +9.0090
           -0.5000   -0.5000    0.0000                    +1.9821   -0.5000   -9.0090
           +9.0090   -9.0090    0.0000                    -1.0000    0.0000    0.0000

TITLE: 10/13 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:
LOG:

15:09 Garilynn into the LVEA

15:17 Betsy into biergarten

15:35 TJ out o HAM5 and then HAM2

15:39 Peter and Jeff heading ino PSL for water leak mitigation

17:04 Marc to MY

17:05 TJ out for a quick break

17:09 Gerardo into HAM5

17:36 Travis, Betsy, and Greg out of LVEA

18:12 TJ and Cheryl out to HAM2

18:15 Marc Back from MY

19:20 Gerardo ad Peter out to HAM5

19:21 Greg to biergarten to prepare chambers fo Monday work

19:27 TJ out for lunch

20:34 Gerardo and Peter back and Peter into the optics lab

20:49 Greg out and gone for the day

21:22 Arnab out to Y Cryopump area with Kyle

21:32 Richard out to CER

21:43 Peter and Gerardo out

Dust Monitor 102 has stopped responding in the last couple of hours and needs to be power cycled/re-started.

Krishna, Jim

This is a slight variation on an earlier duty cycle analysis by Jim. I'm trying to establish how the new ISI-Stage1 control scheme implemented in O2 at LHO benefited the interferometer. As a reminder, in O1, we only used feedback from the Stage 1 seismometer and switched between the 45/90 mHz blends to combat microseism/wind respectively. In O2 we used 'tilt-subtracted' feedforward at low-frequencies and 250 mHz blends as the nominal configuration on all platforms including the HAMs. The data lives in:  SeiSVN/seismic/Common/Data/LHO_O1_O2_duty_cycle_data

The first attachment shows plots for duty cycle versus wind for O1/O2. It uses the minute trends of ISC Lock State and the ETMY windspeed (max) signal. The first page simply shows the distribution of wind - fraction of time windspeeds were in a given bin (bins were ~2 mph) during O1 and O2. The second page shows the fraction of the time the interferometer was locked at a given windspeed. Not only is there a clear improvement in O2, but the curve looks flat up to a windspeed of ~30 mph unlike in O1. The overall duty cycle in O2 seems to have suffered a bit, possibly due to other reasons. Pages 3 and 4 show similar plots, but only comparing the 45 mHz blends used in O1, which are still the default configuration at LLO. Again, it is interesting to note the downward trend on page 4 for the 45 mHz blend, which suggests that even 10-20 mph winds would begin to impact the interferometer.

The second attachment has very similar plots for duty cycle versus microseism velocity, using the band-limited-rms ITMY_Z (max) signal in the microseism band. The O2 configuration looks better once again and there is a similar trend of nearly flat duty cycle up to ~1300 nm/s velocities in O2. The distribution of the velocities looks odd/different, partly because of the inclusion of Hanford summers in O2, which are very quiet in the microseism.

S. Dwyer, J. Kissel

This completes the investigation of the broken beam dump found in HAM6 (see LHO aLOG 38918) -- the beam dump has been identified as the OMC REFL Beam Diverter Dump. 
This beam dump captures light *down stream* (toward the OMC) of the fast shutter.
The dump was broken in a relatively clean vertical fracture which lines up with the dump's set screw, and when reconstructed appears to show a small pock-mark from an apparent small laser blast.

While there's no way to prove why it broke, we have two main suspicions:
   - The black glass is secured to the dump's mount with metal set screws. It has been suggested that all such black glass should be secured with PEEK set screws. If not, these metal screws create un-due stress on the glass, especially if over-tightened.
   - During observation, it has become standard to leave the OMC REFL path's Beam Diverter CLOSED, i.e. blocking the path from hitting the OMC REFL QPDs and/or exiting HAM6 onto ISCT6. Thus, during some high-power lock loss in which both
      - the fast shutter protection failed, leaving the OM2 > OM3 > OMC > OMC REFL path exposed, and
      - the OMC was unlocked sending lots of OMC REFL light down the REFL path (instead of through the OMC, if it were locked).


Picture highlights and labeled drawings are attached as .jpgs, and a more complete collection of pictures are compressed as a .pdf.
Regarding the metal set screws on this dump: a survey of other similar beam dumps in the chamber indicate that *all* such dumps in HAM6 are secured with metal set screws (see 2017-10-11_HAM6_BumpDump_SetScrews.pdf).

Open question:
   - Was the beam diverter closed when the shutter failed and killed the OMC DCPDs in Aug 2016 (LHO aLOGs 28820 and 28842)?
   - If closed, did we inspect this path / dump when we went in to fix the DCPDs?
       This picture from the Corey's Resource Space collection show that the dump is at least intact then.