ETMY violin mode2 has been growing, and the RMS is currently at 3.64, so heading to 4.0, and the peak in Cal_Delta is at 1.7e-16 and growing, however, I can't type in a gain to damp the mode.  My first try the gain was loaded for a few seconds and then turned back to zero.  Very soon this will be big enough to cause problems.   I don't see any other Operators that have taken H1 out of Observe to damp.

TITLE: 04/13 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 107Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    Wind: 11mph Gusts, 9mph 5min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.54 μm/s
QUICK SUMMARY:  locked for 7 hours, useism is trending downwards

TITLE: 04/13 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 107Mpc
INCOMING OPERATOR: Cheryl
SHIFT SUMMARY: useism has grown to 0.4um/s. On a 8 hour lock but had a few planned commissioning activities in the beginning of the shift.
LOG:

• 0011 Observing, done with planned commissioning
• 0121 Out of Observing to fix OMC ASC issue
• 0123 Observing

Jenne, Sheila

We tried to move the OMC ASC to the dither servos, we were in low noise with the dithers on from about 0UTC April 13th until 1:21 UTC, but we have now reverted to using the QPDs because we saw that the optical gain was decreased by using the dithers.  We will have to come back to why these are not working.

The first time that we tried to transition to the dithers while DARM was locked on RF, the OMC unlocked.  The second time, we were able to engage the servos but they had a very slow oscillation (~15 minutes) and we could see signals in the Q quadratures.  We transitioned back to the QPD servos and introduced offsets.  We phased the dither demods to reduce the signals in Q while the offsets were on, and closing the servos brought the OMC transmission back up (once we removed out offsets).  

However, watching the trend of kappa_c over the first hour of the lock we can see that the optical gain was low and getting worse, in other locks kappa_c is consistently between 1 and 1.02, in this lock it started at 1 and dropped to 0.99.  at about -200 seconds in the attachment you can see that the optical gain goes right back to 1 when we dropped out of observing to swtich back to the QPD alignment servos.  It also seems that kappa_uim and kappa_pum respond to the change in OMC alignment, which seems funny.  

ETM spot moves, phase 1.  These spot moves are *very* slow, and so are happening while we are in Observing. 

I began at 20:52:15 UTC by turning off the ADS loops that control the ETM spots on both arms (pit and yaw, 4 and 5).  I left on the PRM->ITMY spot loop. 

I moved X Soft in yaw, since Anamaria et al. said that that was the most interesting one, back in March (alog 47606).  Since the spot on ITMY is still servoed, the spot on ITMX should be roughly the same the whole time, thus primarily making an ETM spot move. 

At 21:28 UTC I roughly hand tuned the ETMX Y2L gain, putting it to 5.5 from the 4.95 value it had been, then continued moving the Xarm in yaw.

At 21:36 UTC, I roughly hand tuned both ETMs Y2L gains, putting EX to 5.9 and EY to 1.8 from the 2.03 value it had been, then continued moving the Xarm in yaw.

At about 21:50 UTC, I *tried* to hand-tune the A2L gains, but typed a bad number into EY pitch, and things didn't go well for the IFO :(  Travis is bringing it back online though.

In the attached screenshot, you can see several metrics as well as the slider values for the optics.  In the bottom right corner you can see that I went one direction for a while, then turned around.  The circulating powers seemed to like the first direction better, but the calibration values for kappa_c and f_c both prefer the second direction pretty clearly.  The Xarm circulating power could be decreasing a bit because we are very nearly starting to fall off of one of the transmission QPDs.  But, the Yarm and PR gain also start to go down, which is somewhat surprising, and certainly real.

Georgia points out that, yet again, the circulating powers seem to be telling us the opposite thing from the kappa_c and f_c, which is somewhat frustrating.  

I will come back to this once we're locked later.

In total, though we didn't budget commissioning time for this, since I caused a lockloss and then we used the lockloss for the on-the-board but target-of-opportunity commissioning of the OMC ASC back to dithering, we were out of observing for 2.38 hours.

TITLE: 04/12 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Travis
CURRENT ENVIRONMENT:
    Wind: 15mph Gusts, 9mph 5min avg
    Primary useism: 0.07 μm/s
    Secondary useism: 0.38 μm/s
QUICK SUMMARY: Relocking after a lock loss from before my shift. useism is rising, nearing the 90th percentile line.

TITLE: 04/12 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: TJ
SHIFT SUMMARY:  Currently relocking.
LOG:

15:46 Christina and Nichole to MY

16:20 Kyle to MY

18:15 Kyle back

Cause is known, but I'll refrain from using names.

Next time we are out of observing, it would be good to reload the guardians for IMC_LOCK, ALS_COMM, and OMC_LOCK.

Travis reminded us again about the annoying configuration difference that keeps coming up in the MC2_M2 Lock filter.  In inital alingment there is a more aggressive low pass used for MC2 when we are locking the X arm with IR.  The DOWN state of ALS COMM was setting this back to the less aggressive low pass used for locking in the main state, but the DOWN state of ALS COMM isn't necessarily re-requested after an initial alignment is done if ALS_COMM is already in DOWN.  This is the drawback of having 4 different gaurdians that set the state of one filter, but in this case it would be hard to avoid.  I've added an only_on statement to the IMC_LOCK guardian so that this should be reset there everytime the IMC relocks, and also copied the statement that sets this up in ALS_COMM from DOWN to PREP_FOR_HANDOFF.  This should make sure that it is set correctly each time. 

For the OMC guardian, I had tried to change the setting for the OMC ASC MASTER gain to 0.02 last night and TJ had loaded that guardian at the lockloss.  However, the gain was reset again in the state which is meant for changing the ASC over to the dithers (currently commented out).  This morning Travis and I set it by hand to the lower gain before going to observe.  I made a parameter in omcparams that is a flag indicating if we are using the dither asc or not, and now the mastergain will be set according to that flag.  The guardian was making changes to these gains in slow steps, but we have been manually doing it in single steps which hasn't caused any issues so the guardian is now doing single steps.  

Did an Initial Alignment after EQs rang down sufficiently.  No issues relocking, other than SRC_ALIGN preferring Sheila's button clicks over mine.

On March 19, half of the proto-type wind fence was extended down to the ground.  We've had a few strong wind events since then and most events tend to get the tumbleweeds tumbling.  But, on 3 and 10 March, there were stronger and longer events (see first attachment) with gusts over 30mph and sustained winds over 20 & 25 mph for 10 & 18 hours respectively.  During these events the wind direction was from ~90° to ~150° ; 90 is normal to fence and 135 would be "NW".  So the second event may have cleaned the fence some but there still remains a few albeit the panel is only 15' wide so how many can it hold anyway.  Photo of the fence from this morning attached too.  Notice that the top edge of the lowest panel is not attached to the bottom of the above panel; this may have allowed some weeds to escape.  I think this shows that over time, the bottom panel will tend to accumulate tumbleweeds.

TITLE: 04/12 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Earthquake
OUTGOING OPERATOR: Cheryl
CURRENT ENVIRONMENT:
    Wind: 12mph Gusts, 6mph 5min avg
    Primary useism: 0.33 μm/s
    Secondary useism: 0.24 μm/s
QUICK SUMMARY:  More EQs still arriving.  Earth is angry this morning.

On Tuesday we increased the mx_stream delay for h1susauxh34 from 1mS to 3mS. At 04:29:09 and 04:29:31 PDT this morning we got 5 CRC errors in total. I have just increased the delay from 3mS to 5mS while H1 is unlocked and reset the CRC counter to zero.

TITLE: 04/12 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Earthquake
INCOMING OPERATOR: Travis
SHIFT SUMMARY: Great until a series of EQs
LOG:

• 11:45 UTC - first EQ allert
• 12:11 UTC - H1 lost lock, I put SEI into Very Large EQ
• list is below, no locking

Last night we moved the SR3 heater, and while doing this we found that kappa C (which is supposed to be proportional to DARM optical gain) went the opposite way of the range.

In particular, when Georgia moved the SRC alignment in yaw, we saw kappa C increase by about 1%.  This made us think we were winning with DARM response.

However, when we looked at the DARM spectrum we found that the response to the 331.7 Hz PCAL line had gone down.  Since the PCAL line signal had not changed, this means that the DARM optical gain actually decreased.

This means that kappa C is going like inverse DARM optical gain.  According to documentation (T1700106), kappa C ought to be proportional to optical gain.

After all the latest model and fitting work by JeffK and Lilli, Jeff installed the appropriate inverse sensing filter (same as for 'usual' darm, but doesn't have the cavity pole in it, and also doesn't have some high freq stuff, since those get take care of in series just after the filter). 

I had been confused at that time, and wondered why the CFTD inverse sensing filter bank also had a whitening filter in it, so Jeff turned it off.  After further looking around today, I discovered that really it's just that the CFTD path does the whitening in a different place than in the 'usual' path for some numerical precision reasons, so we really did need that whitening filter on.  So, with the updated inverse sensing filter, and the whitening filter correctly on now, and also the integer number of delay cycles set to 9 to match the 'usual' DARM path, the CFTD version of DARM seems to be ready for use.

It looks like there is some discrepancy at high frequencies that I don't yet understand, but otherwise I think we can use the CFTD version for references when we are doing tests.

Craig, Danny, Georgia

Today we stepped the SR3 heater down in 0.5 W steps, from 5W to 3.5W, according to plan. Here's what we found as we reduced the heating on SR3:

Buildups, cavity pole

• the DARM coupled cavity pole increased by a few Hz
• the optical gain (Kappa_c) decreased by ~2%
• POPAIR_B_RF18 decreased by ~5%
• The BNS range went up ~4 MPc, maybe this peaked at 4W on the SR3 heater
• The changes in arm power were only slight - maybe went up a little ar 4.5W, but decreased after that?

These values are shown in the first attachment, The kick in many signals just before we stepped down to 3.5 W is explained below.

DARM plant and laser noise couplings

We also monitored the DARM plant, frequency noise coupling, intensity noise coupling, and RF9 RIN coupling at each step.

• Craig will post the DARM plant and frequency noise measurements
• The intensity noise coupling at high frequency got worse as we reduced the heater power (second attachment shows darm during noise-buget-style ISS second loop intensity noise injections)
• The RF9 RIN coupling reduced slightly at 4.5W and 4W but was increased again when we measured at 3.5W (third attachment shows the 9MHz RIN excitation to DARM transfer function)

SRC ASC

While we were sitting at 4W on the SR3 heater we checked for detuning in the SRC ASC. This is the big peak in RF18 and RF90 in the first attachment; the 4th attachment is zoomed in during this time. We opened the loops and moved the sliders (top right plots), found nothing too interesting in pitch, but while aligning yaw we saw:

• some gains in RF18, but
• increase in RF90 (maybe we were aligning the SRC to compensate for a misalignment in the PRC?)
• a 2% increase in kappa_C (!)
• a 25 Hz drop in the cavity pole (!!)
• a corresponding dip in the range

We were surprised that the optical gain increased, that doesn't seem to hang together with the other pieces of information here. Maybe we should consider operating with 4W on the SR3 heater, and re-phasing the SRC ASC for this. [Edit: notes for attachment 4: at t = -4500s we turned the SRC ASC back on, which is why the alignment went back to its nominal level. The calibration lines were off before t = -4800s, and the calibration values before this time are not to be trusted.)

Other notes:

• The SR3 cage servo (really an oplev servo) was on for this measurement, this kept SR3 servo'd in pitch, but uncontrolled in yaw
• At 3.5 W on the SR3 heater we encountered a very slow (~2 minute period) oscillation in the corner DOFs. This settled when we returned the SR3 heater to 5W. We spent a bit of time tongiht with the ADS YAW DOFs off, to stop them from oscillating.
• We spent 2 hours and 34 mins out of observing today to do these tests, comfortably within our allotted 3 hours :-)
• While we were out of observing to make measurements we chopped the OMC ASC master gain for Sheila.
• To run our excitations we connected two LSC AO extra channels at the PSL racks to the common mode board excitation, and the 9MHz EOM excitation port, these need to be disconnected again.