Corey, Nutsinee

Few minutes before the lockloess we noticed DHARD, IMC-F_OUT16, and ETMY DRIVEALIGN was running away on the FOM. No earthquake report from USGS within half an hour before/after the lockloss. No seismic activity in the earthquake band. I've attached some lockloss plots below. All the pretty much ASC signal were running away exacpt DSOFT and CSOFT.  WITNESS channels show BS, ETMX, ETMY, PRM, and SR2 running away. I've (temporarily) added IMC-F, ETMX and ETMY DRIVEALIGN to the plot.

Although it's technically Fri morning, I did check on the PSL chiller since its on the Thursday section of the Operator Check Sheet.  Tonight I topped it off with 100mL of water (it was last topped off yesterday with 150mL).

TITLE:  10/23 OWL Shift:  07:00-15:00UTC (00:00-08:00PDT), all times posted in UTC     

STATE of H1:  Observation Mode at 77Mpc

Outgoing Operator:  TJ

Support:  On Call-->Kiwamu

Quick Summary:  TJ walked me through the the special state H1 is in (running 45mHz blends & manual shuffling in the ENGAGE ASC PART3 step); this hub bub is all related to the elevated useism (it's currently around 0.03um/s).  TJ/Sheila felt the Blends were possibly having issues with the Soft Loop FM1 gains, so they are kept ON for this lock (FM1, -20dB gain is ENABLED).

We'll see how we do during the night as to whether we should run with these filters ON or OFF

• Title: 10/22 OWL Shift: 23:00-7:00UTC (16:00-00:00PDT), all times posted in UTC
  

• State of H1: Observing at 78Mpc
  

• Support: Sheila, Jeff K, Jim W.
  

• Shift Summary: Worked for awhile to overcome the useism, eventually seemed to find a working configuration, but lost lock an hour before the end of my shift.

• Incoming Operator: Corey G.

•  

• Activity Log:

• 23:37 Keita to LVEA to electronics racks
• 23:53 Keita back
• 00:00 Keita out again
• 00:12 Kiwamu to CER
• 00:15 Kiwamu and Keita back
• 00:18 Start Initial Alignment
• 00:24 Kiwamu in and out to check lights
• 00:54 Initial Alignment done, starting locking
• 01:57 Switched to 90mHz blends on BSCs
• 02:04 Switched to 45mHz blends
• 02:43 Started switching blends while in DC_READOUT
• 03:45 Nominal Low noise
• 04:17 Observing
• 06:06 Lockloss
• 06:49 Observing

H1:LSC-POP_A_LF_OUTPUT had an oscillation grow.

Useism still high (peaks at 0.5um/s)

Possible eathquake that was trending down that may not have helped (4.5 in Argentina says USGS).

Winds < 10mph

I will post Lockloss plots after I get this up again.

After about 9 hours of being down, we are now in Observing. BUT we are not is our normal configuration setting. Here is what worked/changed:

• Saw that the ASC PRC2 was pushing PR3 and kept running away with the lock. This is a sign of bad alignment so I did an Initial Alignment.
• We played with blends in different configurations and tried to change them while in DC_READOUT(partially unsuccessful, read below for more). The 45mHz blends seemed to work best with this high useism.
• Kept the SOFT loops in Low Gain (accepted in SDF). These are normally changed to high gain in the ENGAGE_ASC_PART_3 step in the ISC_LOCK Guardian. We did not edit the Guardian with these new settings, we just manuvered around in manual and did some by hand. Sheila suggested that we could turn them to high gain later in the locking sequence, but risk dropping the lock. So after waiting in NLN for ~10min, we decided to leave them in low since the range seemed just as stable and the glitches were not any more frequent.

The current configuration settings that are different than our normal are: SOFT loops in low gain and BSC blends at 45mHz. Future operators may need to change these back for future locks, depending on conditions. (OpsInfo tagged)

More on the blend switching

The 90mHz blends seemed to not do well with the ALS during the high useism. Looking at the ALS X/Y power on Striptool, there is visible movement in the power while in the 90's, but not while in the 45Hz. After the the Engage ASC steps, it seemed as though the 45's would become unstable. Sheila thought that the 90's may be better after we have transitioned off of ALS, so we thought to try to switch blends after getting to DC_READOUT.

When we got to DC_READOUT I first changed the ETMX X blend from 45 -> 90. This worked with some disturbance seen in AS90. I moved on, with Jim W giving me some advice, and changed ETMX Y to 90. This also didn't drop us out of lock, but the AS90 trace wasn't getting any better. Next ETMY Y -> 90, same as the last two. And finally what did us in was ETMY X -> 90. Not sure if it just couldn't hold the instability anymore or if that particular dof just didnt agree with the change.

Since the ends were in 90 and the CS was in 45, I figured let's try it like that. ALS power looked slightly better than with 45 all around, but much more jagged and not as consistent of an oscillation as with all 45's. This configuration couldn't make past the first couple of steps, similar to all 90's.

Switched back to 45's and stayed here. When we got to DC_READOUT the next time all seemed well and we moved on to NOMINAL_LOW_NOISE.

TJ, Jeff K, Jim W, Sheila

We are on 45 mHz blends today, with microseism and wind that TJ will post. The first attached screenshot shows that today at least the optical levers show more motion when we are on 90 mHz blends. 

We are also running with low gain in the SOFT loops today.  We struggled with locklosses when turning up the gain in these loops (similar story in alog 22447).  This seems to be related to the 45mHz blends, because the gain peaking with these blends is unfortunately near something a little unstable in these loops with their nominal gains.  So it may be that we are best off to use low gains when we are on 45 mHz blends (FM1 off for all soft loops)  screen shot is attached.  Operators can probably let these come on in ENGAGE_ASC_PART3 and then manualy turn them off.  If this is not woking you can call me, we can add a check on the blend configuration in the guardian.  With low gain in these loops we do not have the large fluctuations in power build ups we had when we locked with 45 mHz blends in the past. The attached screenshot shows that when we used the 45 mHz blends in the past (22477), there were rather large fluctuations in POP LF (500 counts peak to peak)  Tonight with low gain in the SOFT loop the fluctuations are more like 100 counts peak to peak.  

For a good part of the afternoon we were struggling to lock because the recylcing gain was too low when the PRC2 loop came on.  We already had a check on recycling gain in the guardian, but the threshold was set too low, 31.5 (or 1050 in TR_X and TR_Y).  I increased the threshold to 34.5 (or 1150 in TR_X and TR_Y).  This means that the operators are now more likely to get an error message in ENGAGE_ASC_PART1 that says "Low recycling gain! Align by hand or redo Intial alingment"  If this happens people can try to align things by hand, (adjusting PR2 would be a place to start, maybe ITMs).  If we loose lock it is probably best to just redo inital alingment.  

We were also loosing lock when the SRC loops were re-engaged after being turned off for the CARM offset reduction. 22554 We edited the guardian to leave them on all the time, because I don't think that was really the problem with the locklosses durring CARM offset reduction. The good news is that we didn't have any trouble with these locklosses today, despite high ground motion. 

I attempted to turn back on the CW injections since they were turned off earlier this week from the power outage.

Upon restarting psinject through the monit web inteface it said it the process was running. However the CAL-INJ_HARDWARE_OUT_DQ and CAL-INJ_CW_OUT_DQ time series were still zero.

I turned off the psinject monit instance and returned the hardware injections to the state they were in.

Seems to be the microseism keeping us down. The DMT monitor is showing levels reaching 0.5um/s. Sheila, Jeff K, Jim W, and I have been trying some different blend combinations and trying to switch from the 45mHz to the 90mHz at DC_READOUT, but just can't seem to make it past that point.  Sheila still has some ideas up her sleeve, so I will update more along the way.

In order to apply the calibration parameters kappas to h(t), we need to low pass it so that the noise (high frequency variation) picked up from the detector is smoothed out and only the low frequency variation, which we are confident is an actual change in the response of IFO, is applied to the data.

The value of kappas (data) obtained from the GDS pipeline is calculated by doing a 10s FFT and stored at 16 Hz to the frame. In order to determine an appropriate low pass filter, I averaged the 16 Hz data at 64s, 128s and 256s. 

The attachment below contains 3 pages of plots for each IFO. I took a day worth of data where there were several locks during the day. The plot on page 1 and 2 are plots for kappa_C and kappa_tst respectively. Each page contains four plots of which the first one is the actual 16 Hz data  with 64s, 128s and 256s averaged data overlayed on top of it. The rest three plot are individual averaged plots.

The plot on the last page is standard deviation of the data after applying the averaging plotted along with the estimate standard deviation as if the variation improved as square root of N. The two agree very closely. This just says that data is normally distributed (could be noise but not necessarily) and variation improves as a square root of average time.

Title: 10/22 Day Shift 15:00-23:00 UTC (8:00-16:00 PST).  All times in UTC.

State of H1: Locking

Shift Summary:  After losing lock early in my shift, I have been struggling to get locked.  After doing initial alignment 1.5 times, we have been getting to DRMI 1f consistently, and made it as far as ENGAGE_ASC_PART3.  Microseism is high.

Incoming operator: TJ

Activity log:

18:55 Adjusted ISS diffracted power from ~11% to ~8% after Guardian complained

20:48 Switched BSC ISIs to 45mHz blends due to high microseism

21:26 GRB alert

21:50 Betsy and Mitchell to optics lab

22:18 Betsy and Mitchell done

• Title: 10/22 Eve Shift: 23:00-7:00UTC (16:00-00:00PDT), all times posted in UTC
  

• State of H1: Unlocked

• Outgoing Operator: Travis

•  

• Quick Summary: High microseism (0.5um/s) seems to have kept the IFO out for the past 5 hours, and it looks like we just had an earthquake (4.4 in Canada) to top things off.

I have taken a look at the recalibrated C01 frames for LLO and LHO.  See LLO alog  21961 , for the LLO version of this.

I grabbed the H1:GDS-CALIB_STRAIN (online) and H1:DCS-CALIB_STRAIN_C01 (recalibrated) data from the Caltech cluster, and generated the ratio of the spectrum at time which we expect both the C01 and C00 to be correct.

The data is stored in the calibration svn at:
https://svn.ligo.caltech.edu/svn/aligocalibration/trunk/Runs/O1/H1/Results/C01

It was generated by the script:
https://svn.ligo.caltech.edu/svn/aligocalibration/trunk/Runs/O1/H1/Scripts/CHECKS/compare_C00_C01.m

Below I attach a ratio of the strain between C01 and C00, from GPS 1128249017 (Oct 7, 2015 10:30 UTC).  This is a time period when the front end models and GDS pipeline matched our best knowledge of the instrument and were used to generate the recalibrated C01 data.
 
This should be compared to LHO alog  22291 , first attachment.  Similarly to LLO (see LLO alog  21357 ), we believe the small 2% differences at low frequency are due to minor mismatches in the front end filter realization against our full calibration model which the GDS filters match well against.

The large narrow frequency 5% differences are around the DARM calibration line (at 37.3 Hz) is similar to LLO (see  21961 ).  The other higher discrepancy is I believe related to the front end filtering handling of certain notches, which Kiwamu had to reduced the Q for in the calibration.  See LHO alog  21332  and  22738 .

Betsy writing on Kissel's account, but on behalf of Kissel for the most part...

Attached are the long trend plots of the ETM charge data taken last Tuesday after the power outage.  Stuart has added a new plot ala Kissel's request which plots ESD actuation strength.  This new plot will be useful in comparison against calibration's estimate of the actuation stregth from calibration lines, aka the parameter "kappa_TST" (for example alog 21817).  The sign flip of the ETMY bias voltage for a couple weeks ago seems to have turned the effective charge voltage back towards zero as expected.

Lockloss @ 18:46 UTC.  Cause is currently under investigation.