Daniel, Nutsinee

OPO didn't lock last night because it couldn't find a dual resonance. The OPO scan starts from 60V to 110V but it should have been 20 to 70V. The lock point prior to down time the dual resonance was found at 64V. We started scanning too close to the lower threshold. After several failures the OPO guardian went to idle and stopped trying for the rest of the night. 

An instruction to ops:

Next time the IFO loses lock, please go to sitemap > SQZ OVERVIEW > SQZT7 > OPO PZT and drag the PZT offset slider bar to 0. See screenshot attached.

TITLE: 03/22 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 12mph Gusts, 9mph 5min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.21 μm/s
QUICK SUMMARY:

IFO was in NOMINAL_LOW_NOISE when I arrived and shortly after H1 was in OBSERVING.
The Lockclock should not be trusted for the duration of this lock because it was restarted 6 hours ago.
The Current Lock has been in NLN and above for over 14 Hours and 30 minutes.
Everything else looks good and is currently running smoothly.
 

TITLE: 03/22 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing
INCOMING OPERATOR: Tony
SHIFT SUMMARY: H1 remained locked all shift, current stretch is at 14 hours (lock clock in control room is inaccurate for this lock), which made for lots of commissioning opportunities.

• 21:21 - NLN_CAL_MEAS for LSC measurements
• 22:43 - Back to NLN
• 23:05 - Started Observing (no commissioning activities desired at the moment)

LOG:

Last night due to some SQZ MANAGER issues, we had a long period without squeezing on. For future reference here is a list of NO SQZ quiet times with no glitches:

First 10 mins of a lock at NLN: GPS 1395133005

then 1395134044 - 1395139295 GPS for thermalisation period of 1 hr 28 mins with no glitches.

Then period 1395139667 to 1395146035 is 1 hr 44 mins about 2 hours into lock.

Then best thermalised period is GPS 1395151019  for 53 mins. (third image).

SQZ time starts at 1395165711 GPS for 53 mins on 22nd March. This was while we were doing our REFLB off test but it should be fine range-wise. (second image)

Calibrated measurement of DARM is shown in first image.

Code located in /ligo/gitcommon/labutils/beam_spot_raster/a2l_gain_stepper.py

Current spot positions (e.g. H1:SUS-ITMX_L2_DRIVEALIGN_P2L_SPOT_GAIN):

It will step the nominal values up and down 0.4 in 0.2 steps / 15 minutes. e.g. starting a2l + [-0.2, -0.4, -0.2, 0, 0.2, 0.4, 0.2, 0]

I've set up a script to run this on ETMY at 6am to 10am tomorrow (23rd) in a tmux session on cdsws26, will only run if the IFO is at NLN (>=600)  at 6am.

Ryan S will try to find times (4 hours each) to run this on the other optics ITMX and ETMX over the weekend, command below. We don't have beam spot control on ITMY so can skip that.

>> python /ligo/gitcommon/labutils/beam_spot_raster/a2l_gain_stepper.py ETMY --start 'now'

Sheila, Camilla, Naoki, remote converations with Vicky

Overnight the squeezing was not injected because of some guardian issues.   The OPO failed to lock, we will look into that separately.

After that the filter cavity did not find IR.  Looking at the logic in SQZ manager, it didn't make sense to me.  We were requesting the filter cavity to IR_FOUND without first locking the OPO or the CLF, but the filter cavity can't find IR until after both the IR and the CLF are locked.  This might have been done to save some time, but it sets up a race condition where we are relying on the filter cavity green locking to be slower than the OPO and CLF locking.  If the filter cavity failed in it's search, then it would stay in FIND_IR and not try again.   I separated the lock OPO and lock cilter cavity states, and rearranged the graph so that the filter cavity isn't requested to lock until after the CLF is requested to lock.  This will take slightly longer but not much longer, and this happens in parallel with IFO locking. We loaded this change and excerised it.

While I was looking at SQZ_MANAGER, I noticed some things that seem potentially confusing and could cause some difficulties with using it.  Several of these related to using the same states for frequency dependent and frequency independent squeezing.  The SQZ manager was looking at the state of the FC guardian to determine if FIS or FDS is desired, in many places.  I changed this so that FIS has a separate path from FDS after the CLF is locked.  This allows simplifying states like OPEN_BDIV (we now have two versions, one for FDS one for FIS).  Some states like LOCK_LO and SQZ_ASC are the same in the two paths, so I've used a generator to make sure that the same code is used in both paths.  Naoki and I checked this, going from DOWN to FDS, FDS to FIS, DOWN TO FIS, and FDS and FIS to no squeezing.  The previous version of the guardian had a path from FDS to FIS, but there was not code to do that so we've now eliminated the path. We made the changes needed to ISC_LOCK, and laoded them.

The guardian before these changes is 27284

The FC_LOCKED checker only checks that the FC gaurdian isn't in IDLE, but it seems to be used througout SQZ_MANAGER as though it was checking the filter cavity is locked.

FAMIS Link:  25983

Only CPS which looks higher at high frequencies would be ETMy Stage 1, H2 (although the terminal did not list it as "high").  (see attached plots).

FAMIS 26236

Laser Status:
    NPRO output power is 1.819W (nominal ~2W)
    AMP1 output power is 67.15W (nominal ~70W)
    AMP2 output power is 138.3W (nominal 135-140W)
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN

PMC:
    It has been locked 21 days, 21 hr 9 minutes
    Reflected power = 16.84W
    Transmitted power = 109.0W
    PowerSum = 125.9W

FSS:
    It has been locked for 0 days 11 hr and 41 min
    TPD[V] = 0.8342V

ISS:
    The diffracted power is around 2.3%
    Last saturation event was 0 days 11 hours and 41 minutes ago

Possible Issues: None reported

After the 76623 frequency noise injections, we left CARM control just on REFL B (H1:LSC-REFL_SERVO_IN1GAIN = 12dB) rather than the nominal  6dB on both REFL A and B. Kept the REFL B only config from 17:39UTC to 18:58UTC.

Plan to look for coherence between DARM and REFL A to check for frequency noise on REFL B (when REFL A is out of loop, acting only as a witness). Plot attached shows no coherence in 100Hz to 1kHz region above 0.04.

Test was maybe redundant after Francisco's 76533.

Sheila, Jennie, Camilla. Following 70642.  Intensity noise measured in 76323.

Plot of laser noise budget attached.  First conclusions: Frequency noise lower, Input Beam jitter slightly higher. Compare to O4a plot (Aug 20 data?) 74943 which is a factor of ~2 worse than Aug 10th 72140.

Jitter noise excitation gain, reduced from frequency range from10,000 to 2000, didn't mean to but reverted the templates and it doesn't matter.

Frequency_excitation.xml adjusted bandstop for dither lock from 4000-4200 to 4090-4290Hz (from 76587).

template: Frequency_excitation.xml

Adjusting  70642 for Switch CARM control from REFL A+B to REFL B only from 60W:

• REFL A and B both have 6dB digital gain with 60W
• Via sitemap > LSC > REFL Servo, step down 1dB on REFL A and up 1dB on REFL B until the REFL A gain is 0dB and REFL B gain is 12dB
• Step down REFL A gain down to -32dB 
• Turn off the input 1 switch (REFL_SERVO_IN1EN) for REFL A

Instead of bringing back CARM control to REFL A and B, from 17:39UTC we left CARM control on REFL B only  to look for some coherence.

Fri Mar 22 10:12:54 2024 INFO: Fill completed in 12min 50secs

Gerardo confirmed a good fill curbside.

Camilla, Sheila, Jennie W

After we restarted the SQZ MANAGER this morning we took the SQZ angle test to see how the squeezing changes with a thermalised IFO if we step through optimum  squeezing through tuning the ADF phase. This ran into some problems when we tried to start at 85 and 90 degrees as the loop seemed to run through a really wide range of phases (we think the loop was diverging). Camilla manually changed the ADF phase to 110 degrees and we restarted the test so it stpped up in steps of 3 degrees every 2 minutes. We changed this halfway through to have a longer time between steps for the loop to follow. The test was stopped at 161 degrees.

We stepped SQZ-ADF_OMC_TRANS_PHASE 

GPS 1395157776  PHASE = 110

H1:SQZ-ADF_OMC_TRANS_PHASE = 113
H1:SQZ-ADF_OMC_TRANS_PHASE = 116
H1:SQZ-ADF_OMC_TRANS_PHASE = 119

H1:SQZ-ADF_OMC_TRANS_PHASE = 122
H1:SQZ-ADF_OMC_TRANS_PHASE = 125
H1:SQZ-ADF_OMC_TRANS_PHASE = 128
H1:SQZ-ADF_OMC_TRANS_PHASE = 131
H1:SQZ-ADF_OMC_TRANS_PHASE = 134
H1:SQZ-ADF_OMC_TRANS_PHASE = 137
H1:SQZ-ADF_OMC_TRANS_PHASE = 140
H1:SQZ-ADF_OMC_TRANS_PHASE = 143
H1:SQZ-ADF_OMC_TRANS_PHASE = 146
H1:SQZ-ADF_OMC_TRANS_PHASE = 149
H1:SQZ-ADF_OMC_TRANS_PHASE = 152
H1:SQZ-ADF_OMC_TRANS_PHASE = 155
H1:SQZ-ADF_OMC_TRANS_PHASE = 158
H1:SQZ-ADF_OMC_TRANS_PHASE = 161
 

Phase was put back to 130 degrees after the test at GPS 1395160576.

First image shows the SQZ BLRMS that show how squeezing gets better and worse during the test, calibrated in dBs. Then below this the CLF phase, the OMC trans phase which we are changing and the range at the bottom.

Second image attached shows the same BLRMS (in counts before and just after the test on the bottom left) and the CLF phase and OMC trans phase on the bottom right. From the blue trace just before the test you can see the sign flip when we tried to start the test at 100.

NB: we had been locked for over 6 hours when we started but squeezing wasn't injected until around 20 minutes before the test started.

As shown in the attachment, I turned on the beam spot control. The flag of the beam spot control in sqzparams is set to True. The beam spot control seems working well, but I feel the yaw was too slow so I removed the -20dB gain (FM7 in INJ_ANG_Y). I will tune the green QPD offset with FC2 dither tomorrow.

[Jennie, Gabriele]

We tried again to move the input beam.

For pitch, we directly ramped IM1, IM3, IM4, PRM and PR2 with sliders deltas measured from the test yesterday. IM1 and IM3 were the mirrors we move yesterday, while the other were moved by ASC loops. Today with the ramp we helped the ASC loops by moving those mirrors in the right direction too. We first diod one step 1/10th of the target step, then 2/10th and then the remaining 7/10th. All went well: IM4_TRANS increased, but we did not see much change in POP_LF. However ASC-POP_B dropped near the end of the ramp, while ASC-POP_A didn't, so maybe we were moving near the edge of B.

We then started a  motion in yaw (both IM1 and IM3 negative). This seems a very good direction, and both IM4 and POP_LF got better quickly. However, right after we started the second step, we lost lock. This is similar to what happened in the previous test. We should probably move more slowly in yaw, but it worth repeating the test, since we are gaining power in POP_LF and arms.

EvanH, FranciscoL

Because we've been loosing lock for unknown reasons, we measured OLG transfer function of MICH, SRLC, and PRLC. The UGF for each one is (see attached figures for reference) roughly

MICH: 10 Hz

SRCL: 12 Hz

PRCL: 35 Hz

We may want to lower the MICH UGF to avoid cross coupling with the SRCL loop.

We tried the in-lock charge measurements but forgot about the New-DARM configuration so caused a lockloss in the SWAP_TO_ITMX state.