Ops Eve Beginning Shift Summary

TITLE: 10/27 [EVE Shift]: 23:00-07:00 UTC (16:00-00:00 PDT), all times posted in UTC
STATE Of H1: Observing @ ~ 71 MPc
OUTGOING OPERATOR: Nutsinee
QUICK SUMMARY:
Lights appear off in the LVEA, PSL enclosure, end X, end Y and mid X. I can not tell from the camera if they are off at mid Y.
Winds are less than 20 mph.
ISI blends are at 45 mHz.
Earthquake seismic band is between 0.01 and 0.1 um/s. Microseism is between 0.1 and 0.6 um/s.
In standdown for GRB until 23:41 UTC.

~1430 -1630 hrs. local -> Anchored Y2-8 ion pump stand to concrete floor

Ops Day Shift Summary

TITLE: "10/27 [DAY Shift]: 15:00-15:00UTC (8:00-16:00 PDT), all times posted in UTC"

STATE Of H1: Observing at 78 Mpc

SUPPORT: Control room folks

SHIFT SUMMARY: Maintenance period went well. There were couple of things that happened before I was informed and both had potentials of interfering with on-going tasks so please do not forget to come by or call the control room to check with operator on duty. We had a little trouble locking DRMI. After locking PRMI everything went smoothly. Jenne ran a2L script and and Evan was doing some measurement before we went to Observing. Then a GRB alert shortly after. The ifo is currently in Stand-down mode.

INCOMING OPERATOR: Patrick

ACTIVITY LOG:

15:08 Richard transitioning LVEA to LASER SAFE. Bubba begins grouting work. PSL is not down. IMC still locks.

15:21 Hugh to EY to check HPI fluid and secure light pipe between table and BSC

15:23 Jeff and TJ to pipe bridge between HAM4 and HAM5

            Ryan patching alog

15:25 Ken to the beamtube 250 meters from end X

           Jodi et al to mid X

15:35 Fil to both ends for temperature sensors installation

           Dale to LVEA taking pictures

15:40 Karen to LVEA and EY to cleam

           Jason to diode room to restart PSL WD

15:48 Hugh leaving EY, heading to EX. Jason out of diode room.

15:52 Christna to LVEA.

           Ryan done patching alog.

           Kiwamu leaves laser at high power for ISS measurement

16:00 Dale back

16:05 Mitchell taking Sprague to LVEA

         Jonathan installing EPICS IOC to monitor Beckhoff PLC

16:14 Jodi to LVEA checking on 3IFO stuff

16:19 Kyle to check on HAM3 ion pump

         Mitchell out

16:27 Hugh done

          Jodi out of LVEA

16:36 Karen out of EY

16:52 Maddie called to make sure it's okay to restart h(t) DMT. Things went well.

17:00 Christina opening the roll up door. Karen called saying she's at EX. Fill also there.

17:18 DMT0 - Ryan Fisher called to say he's restarting some process and shouldn't affect anything. Next time if people don't speak English-English I'm just gonna hand the phone over to Jeff Kissel.

17:26 Jeff done with charge measurement (started about an hour ago).

          Evan to LVEA installing cable at ISC rack (R1 to R4).

17:41 Fil done at EX. Heading to EY.

17:44 Jeff K. begins EX charge measurement.

17:48 HAM2 tripped. Jeff K. recovered everything. HAM2 ISI switched to low gain.

18:04 TJ and Jeff B. done

18:13 Kiwamu and Sudarshan to LVEA measuring ISS second loop TF.

18:17 Richard at EX pulling some cable.

18:18 Hugh to HAM1 to check on grouting.

18:22 Hugh out.

18:44 Jeff done with EX charge measurement.

18:46 Jodi back from the Mid.

          Kiwamu out

          Grouting done

18:48 DAQ restart (Jim B)

18:59 Kiwamu done with ISS for the day.

19:01 NDS not come back. DAQ restart again.

         Fil done at EY and done with all temperature sensors installation.

19:06 Richard leaving EX

19:50 Begins initial alignment. Cheryl and Jeff K to LVEA doing sweep.

19:52 Cheryl to Optics lab

20:07 Cheryl out

20:45 Kyle to anchor ion pump 275m from EY.

          Richard to HAM6 to put on safety sticker.

20:58 Richard done

21:52 Evan to unplug the cable.

21:56 Evan out.

21:59 Observing/Sciencing

22:40 GRB alert. Stand down.

 

I don't see this reported elsewhere in the log, but the DAQ restarts seem to have introduced a large (5 minute?) lag in the calibration pipeline. To fix this, Maddie restarted the pipeline at about 21:04 UTC (14:04 PDT). This resulted in a few (unlocked data) h(t) frames being lost, but the pipeline latency is reduced to ~11s.

HAM 1 HEPI PIERS

The HAM 1 HEPI piers have been grouted. If there is a lock loss at some point tomorrow or the following day, it would be good to go into the LVEA to remove the grout forms.

GRB Alert 22:40:40 UTC

DO NOT TOUCH THE IFO (for at least an hour).

Back Observing 21:59:47 UTC

Crusing at ~78 Mpc.

New CAL_LINES.adl screen

I made a new screen to help Operators check the status of the CAL lines. It shows the current value of the sine waves with their amplitudes and frequencies as well as the status of the Optical Follower Servos. The OFS Oscillation Monitor will have a green border if the absolute value stays under 0.01, and red otherwise. There are links to each of the line's medms for more information, if needed.

This is located under the CS CAL on the Sitemap.

Outreach activity report (Friday, 10/23/15)

LHO's fourth-Friday public tour occurred on the afternoon of 10/23.  Arrival time at LSB = 2:30 - 3:00 PM.  Departure time = 5:00 PM.  Group size = ~12 adults.  Vehicles at the LSB = ~6 passenger cars.  The group was on the overpass near 4:15 PM and in the control room from about 4:30 to 4:50.  

Maintenance Recovery Complete @ 2:05p PDT!

J. Kissel, N. Kijbunchoo, S. Dwyer

After a pretty breezy maintanence day, we've successfully achieved nominal low-noise in record time.

Good job team!

P.S. We're going to run a few commissioning measurements before heading into observation mode. Expect science in about a half hour.

ISS 2nd loop maintenance today

Sudarshan, Kiwamu, (WP#5569)

During the maintenance period in this morning, we looked at a few things in order to improve the ISS robustness.

In summary, the 2nd loop ISS is not back in a great shape yet. There will be some times where it needs the manual engagement.

 

(1) The open loop measurement suggested that the UGF is at 10 kHz with a phase margin of about 50 deg. No crazy thing was found.

(2) The PID loop seems to have been suffering by unidentified extra offset, which explains the behavior we saw yesterday (alog 22863). I have edited the IMC_LOCK guardian so that it servos to a better locking point where the transient is less in the diffraction power.

(3) The IMC seems to be adding extra intensity noise below 1 Hz. This is the main reason why the PID loop does not converge simply because it is too high.

Change in the PID locking point

After a number of the 2nd loop engagement tests, I confirmed that it was the PID loop which pulled the diffraction power to a small value (alog 22870). This happens even without any additional gain or boosts which are engaged in the CLOSE_ISS loop. The reason of this bad behavior was found to be due to a different (unidentified) offset in the SECONDLOOP_SINGAL. I do not know why it changed. Originally the guardian was supposed to servo SECONDLOOP_SIGNAL to 0.7 which had been fine in the past in terms of transient kick to the first loop. However, as reported in the recent alogs, this locking point became bad in the sense that it gave a too large kick and eventually unlocked both 1st and 2nd loops. I experimentally adjusted the offset point which ended up with -0.4. I have edited the guardian accordingly and checked in to the SVN.

I then tested the manual engagement with the new PID locking point multiple times (Note, I did it manually because the PID loop was not able to converge due to large motion in the IMC). I confirmed that it did not pull the diffraction to a small value. Though it often lifts up the diffraction up to about 10% which is acceptable.

Extra intensity noise from IMC

This is something we already knew (alog 22482), but intensity noise became higher at low frequencies as the light goes through the IMC. This is likely due to some static misalignment somewhere (or perhaps very large offset in the length control) in the IMC. In order to identify which optics are contributing most, I looked at several channels for SUS-MC1, MC2 and MC3, and HAMs 2&3 table motion. However, sadly, all three MC optics and both HAM tables seem to equally contribute to the intensity fluctuation seen in MC2_TRANS and ISS PD array below 1 Hz according to coherence. The contribution from yaw tend to be larger than that of pitch according to the coherence, but they all are above a coherence of 0.85 or so below 1 Hz. It is difficult to say what optics are contributing most.

We need to study why the IMC motion is so high these days.

For those who will engage the 2nd loop in the future

The manual engagement now works fine. As usual, when the 2nd loop does not engage on its own for more than 5 minutes or so, please follow the instruction for the manual engagement (alog 2249). Also, when the manual attemp fails (i.e. the deffraction power is pulled by more than 5 % when manually engaging), one can prevent a lockloss by manually disengaging the second loop input (the very top red button in the 2nd loop ISS screen). Subsequently one can make another attempt once the diffraction power settles.

PRMI to DRMI transition

We implemented a version of the PRMI to DRMI transition that Stefan did by hand 20698 a few weeks ago (22472).  It has worked a few times and not worked a few times, operators are using this only when the DRMI alignment is bad to improve alignment in PRMI. Here are plots of two examples of a sucessfull and unsucesfull transition.  (failure at 20:37:19 UTC today, Oct 27,  sucess at 10/26 23:35:05 UTC )  

In the failure, the PRMI lock was lost when the SRM suspension started to realign SRM, before any feedback came on.  Jeff and I changed the ramp time for SRM in the guardian to 10 seconds (I think the default is 2 seconds).  We will see if this helps the PRMI lock to survive realigning the SRM.  

Also, in the sucessfull attempt the SRCL feedback came on at a time that AS90 was high, and POP90 was low.  It might be that triggering the SRCL output on one of these channels would be better than POP18.  

WHAM1 Intertial Spectra Post Grouting--No Dramatic Changes

JeffK HughR

Attached are the Blend Input from the L4Cs and the Ground Seismos.  Reference is from 4am today and the current is from about 1230pdt.  The L4Cs are in the first 2 columns and the ground  STS2s coming into the Sensor correction path are in the last column.  The increase in motion seen is a direct reflection of increased daytime ground motion.  Does not look like there is any increase in motion not attributed to the ground motion.

H1 BSC Temperature Sensors EX/EY

Temperature sensors for BSC9 and BSC10 were installed this morning. Sensors were installed on southeast corner of each chamber (next to SUS-R1 rack).

List of activities done at each end station:

EX
1. BNC cable from electronics room (PEM-C1) was pulled back from PEM area in VEA and routed to Southeast corner of BSC9. 
2. Power cable was pulled from SUS-R1 to BSC9.
3. Temperature sensor was installed by using a C-clamp to hold sensor securely next to chamber outer wall.

EY.
1. BNC cable was pulled from electonics room (PEM-C1) to southwest corner of BSC10. 
2. Power cable was pulled from SUS-R1 to BSC10.
3. Temperature sensor was placed in final location, but not secured by C-Clamp.

HAM3 .6hz investigation, comparison to HAM2

BrianL, JimW

Brian and I are investigating the HAM3 .6hz, looking at the tfs we took post chamber closeout in 2014. Brian wanted to look for the possibility of some magnetic coupling from the actuators to the sensors, so we were looking more closely at the cross terms in the transfer functions. We looked at a lot of the cross couplings, but most of them were uninteresting. We thought we found something on the V3 actuator on HAM3 (first pdf) at about .65 hz, but when we looked at HAM2 (second pdf), the feature is even bigger, so we suspect that this is maybe due to the payload. It is suspicious that the vertical drive to horizontal coupling changes slope at about .6 hz, but not very conclusive. 

I've also attached the script that we used to make the plots, but to run it you will have to correct the path to the data. The measurements we looked at were H1_ISI_HAM2_TF_L2L_Raw_2014_09_16.mat and H1_ISI_HAM3_TF_L2L_Raw_2014_09_10.mat in the HAM2 and HAM3  /Data/Transfer_Functions/Simulations/Undamped folders in the Sei SVN. 

EndY ISCT to Chamber Light Pipe Secured

Did not remove the existing pipe and the duct like pipe covers the lexan slot so that can not be used.  Just loosened the hose clamp pulled the duct to completely cover the partly exposed slot and retightened the hose clamp--more than it was.  Less likely to move now.

Tidal Trip 25 Sept--Looks like Temps in PSL

Kiwamu reported in 22781 about a couple lock losses due to the drive to HEPI hitting the 250um limit.  HEPI can handle more than this but should not need to if the PSL (likely Ref Cav) temperature does not trend off somewhere.

Attached are several PSL Temp channels for 14 days with the limit hit time noted on the run away Tidal Channel.  Certainly many of the PSL Temp channels show a trend that correlates pretty well with the run away.  In iLIGO we had tight temp control of the Ref Cav, do we have a temp of the Ref Cav now or is there another signal that would best represent that?

Tidal offloading performance over the past 45 days

Daniel, Sheila, Evan

Summary

Over the past 45 days, we had two instances where the common-mode length control on the end-station HEPIs hit the 250 µm software limiter. One of these events seems to have resulted in a lockloss.

Details

The attached trends show the ISC drives to the HEPIs, the IMC-F control signal, and the IMC-F offloading to the suspension UIMs over the past 45 days. One can see two saturation events: one on 25 September, and another on 11 October.

We survived the event on 11 October: the EY HEPI hit the rail, and counts began to accumulate on the EY UIM, but the control signal turned around and HEPI came away from the rail. On the 25th of September, both end-station HEPIs hit the rail, and after about 2 hours of counts accumulating on the UIMs, IMC-F ran away (second attachment). Note that both HEPI drives started at 0 µm at the beginning of the lock stretch.