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Reports until 09:18, Wednesday 22 July 2015
H1 IOO
betsy.weaver@LIGO.ORG - posted 09:18, Wednesday 22 July 2015 - last comment - 09:20, Wednesday 22 July 2015(19831)
Rotation stage poor performance - no new news here

Attached is a 6 day trend of the H1IMC-PWR_IN showing how the rotation stage finds a variety of stopping places when executing the same request.  This is a long-time known issue, so I'm just reposting to make the problem visible again.  In theory the asc/lsc is supposed to compensate for power-in differences, but a it's hard to hand-wave off a ~25% difference from one down state to another - it makes troubleshooting slow acquisition more muddied than it already is.

Images attached to this report
Comments related to this report
betsy.weaver@LIGO.ORG - 09:20, Wednesday 22 July 2015 (19832)

And here's the high powere full lock rotation stage power request compared to the actual power.

Images attached to this comment
H1 General
jeffrey.bartlett@LIGO.ORG - posted 09:16, Wednesday 22 July 2015 (19830)
08:30 Meeting Minutes
Earnest from Caltech on site for property checks

SEI: 
   Prep for Thursday maintenance

FMC:
   A wooden post near the chiller yard was knocked down. Bubba is repairing.
   Beam tube cleaning on the X-Arm continues
   Joint sealing continues on the Y-Arm

Thursday Maintenance Activities:
   PSL - PMC alignment
   FSS – Electronics upgrade 
   BSC-ISI – Payload watchdog fix
   PCAL – End-X clipping investigation
   LYLN – Driver commissioning
   Cosmic ray detector work
   HEPI – Accumulator fix End-Y
H1 CDS (DAQ)
david.barker@LIGO.ORG - posted 08:21, Wednesday 22 July 2015 (19828)
CDS model and DAQ restart report, Tuesday 21st July 2015

attached is the restart report for Tuesday maintenance. The frame writers appear to be more unstable following the fiber channel change.

Non-image files attached to this report
H1 CDS
jeffrey.bartlett@LIGO.ORG - posted 08:05, Wednesday 22 July 2015 (19826)
Reset CDS Errors
CDS errors reset this morning:

   TIM - H1IOPSUSEY, H1SUSETMY
   ADC - H1IOPSUSEY, H1IOPSUSEX
   IPC - H1SUSETMY, H1SUSTMSY, H1IOPSEIEY, H1ISIETMY, H1IOPETMX

DIAG RESET command cleared all errors. 

LHO VE
bubba.gateley@LIGO.ORG - posted 07:19, Wednesday 22 July 2015 (19825)
Beam Tube Washing
Ed P. Mark L.

7/20/15- VERY HOT AGAIN TODAY
The reduced size and somewhat new crew finished moving lights, generators and support equipment to the next section to begin cleaning.

We also had some cord repair to do. We changed out the U-ground style cords on the vacuum machines for a twist lock style plug. Additionally we made some 250' long AWG #10 S. O. cords with twist lock ends and installed strain relief at the generator. 

33.5 meters of tube cleaned ending 14.5 meters east of HSW-2-069.

7/21/15

Ed P. Mark L.
The temperature has dropped slightly and is supposed to continue a cooling trend for the next couple of days, this makes being in the enclosure much more bearable.

The crew cleaned 67 meter of tube today ending at HSW-2-065.

We relocated the generator and cords. The new cords are working very well.

Rodney is scheduled to return on 7/22/15. The crew will then be back to a full compliment of personnel.

H1 ISC
sheila.dwyer@LIGO.ORG - posted 02:06, Wednesday 22 July 2015 - last comment - 06:40, Wednesday 22 July 2015(19821)
work tonight
Jenne, Sheila, Evan
Comments related to this report
jenne.driggers@LIGO.ORG - 02:20, Wednesday 22 July 2015 (19822)

A2L notes:

The new A2L values hadn't been saved to the safe snapshot, so when there were boots and burts earlier today, the values were lost.  This is why we re-ran A2L for the test masses at high power tonight.  Those values were accepted in the SDF system.  This should be done every time the script is run.  Since I don't know if it's possible to do this in a scripted way, we'll have to do this accepting by hand for now.

In addition, the script a2l.py was modified to be able to handle the BS in addition to the test masses.  The only change for this was an "if" statement at the beginning to define the drivealign channel names (they're in L2 for the quads, but M2 for the BS).  We found that excitation amplitudes of 300 cts for pitch and 150 cts for yaw give us an SNR of about 100 in OMC_DC, so those have been added to the GetOptList.py dictionary-creator.  Sheila tells me that the BS M2 is roughly 3 times stronger than the quads' L2 stages, and these excitation amplitudes are about 1/3 the quads' values, so that all makes sense.

The A2L is finishing up right now for BS, so in the next few minutes we'll have all 4 test masses and the BS all decoupled via Hang's new script.  EDIT:  Pitch worked, but Yaw isn't finding a happy place, so I'll have Hang look at this with me tomorrow.

I also added some lines in the "disable dither" function of a2l.py (which runs if you ctrl-c out, or when the measurements are finished) to reset the CLKGAIN excitations to zero for both the ASC oscillator and the LSC demodulators.  The script already zeroed the output matrices, so the signals weren't going anywhere, but it made me unhappy to have mystery oscillators running unnecessarily. 

evan.hall@LIGO.ORG - 06:40, Wednesday 22 July 2015 (19824)

I tried to get an OLTF of dHard pitch at 24 W, but somehow I rang up a 1.0 Hz instability and had to abort and bring the power down to 3 W. Strangely, even at 3 W this instability took a minute or so to ring down. I tried lowering the master ASC gain to 0.8 temporarily, but this did not make the ringing go away (so it is probably not a loop instability).

At 3 W I was able to get a preliminary measurement of the dHard pitch loop down to 1 Hz. More refinement required.

Images attached to this comment
H1 ISC (ISC)
stefan.ballmer@LIGO.ORG - posted 21:37, Tuesday 21 July 2015 (19818)
DHARD aand DSOFT for YAW
lowered DHARD_Y gain from 14 to 7, DSOFT_Y from 0.2 to 0.1, and updated the output matrix.
Images attached to this report
H1 INJ
jeffrey.kissel@LIGO.ORG - posted 21:26, Tuesday 21 July 2015 (19817)
Attempt to restart CW injections appear to have Failed
J. Kissel

We restarted the h1hwinj1 and h1hwinj2 injection machines today to check whether they were contributing to the recent EPICs freeze problems we've been seeing on control room work stations. The reboot did NOT help the problem. However, since they've now been restored, I figured I'd try my luck at using Eric's instructions on how to restart them (LHO aLOG 18831, T1400349). 

While I was able to log on to h1hwinj, find the appropriate directory, and start_psinject, after the 60 sec start up time, I did NOT see the injection start (looking at the excitation channel in the H1:CAL-INJ_CW_EXCMON or H1:CAL-INJ_HARDWARD_OUTMON), nor does the CAL-CS GDS_TP sceen indicate that there has been a test point selected, even though the interaction with start_psinject was as follows:
-bash-4.1$ ./bin/start_psinject 
Currently, we are running on: h1hwinj1.cds.ligo-wa.caltech.edu
Result of checking injection status: H1 injection is NOT RUNNING
  Automatic restart should occur within 10 minutes; no human action is required
H1 injection will be started with configuration ER7 if you proceed

For logging purposes, please enter your name     (or Ctrl-C to cancel)
Jeffrey Kissel
Type a BRIEF explanation (a few words) for why start_psinject is being executed
Hardware Injection Machines were restarted today to see if they were affecting EPICs slowdown seen in the control room. See LHO aLOG 19809.
Starting H1 injection into H1:CAL-INJ_CW_EXC on h1hwinj1.cds.ligo-wa.caltech.edu using ER7
exec /data/scirun/O1/HardwareInjection/Details/bin/exec_psinject_from_script /data/scirun/O1/HardwareInjection/Details/pulsar/ER7 /ligo/apps/sl6/gds-2.16.12 H1 H1:CAL-INJ_CW_EXC 1121573769
Injection will start at t=1121573769 (60 seconds from now)...
Injection starting now
-bash-4.1$ 


Also -- while the hardware injection machines were down, there was NO indication on the injection overview screen that the hardware injection machines were down / dead. In fact, since the EPICs records that *are* shown on the screen are all defined and stored in the front-end, they had been left in the ALL GREEN state making it deceivingly look like all is well. There should be a look-alive heartbeat EPICs variable sent from these machines, or at least a static alarm bit somewhere to indicate that these injection machines are down or up.
H1 CDS (CDS, DetChar, GRD, INJ, ISC, SEI, SUS)
jeffrey.kissel@LIGO.ORG - posted 20:48, Tuesday 21 July 2015 (19813)
7/21 Maintenance Day / Relocking Team Debriefing
J. Kissel, B. Weaver, N. Kijbunchoo, T. Sadecki, E. Hall, S. Dwyer

Another heavily loaded Tuesday today. For what we planned to do, see LHO aLOG 19770. We have managed to complete the IFO recovery, on the same day, and before the sun has gone down!! Most of the failures and deviations from plan today were software problems, which didn't fix the problem they'd intended to fix, were slow to recovery, or had to be reverted because of new found bugs. Towards the tail end of recovery, there were other problems that were more related to half-finished or mistakes from commissioning last night, but thankfully by the time we had reached recovery the guilty commissioned had arrived on site and confessed their sins. In summary -- not so bad -- but there was little IFO systems' software actually restarted. 


(All times PDT)
07:00 Richard brings SEI platforms and SUS to SAFE/OFFLINE LHO aLOG 19778

07:30 Richard, Daniel and Fil swap the internal GPS of the timing master for the external GPS unit. LHO aLOG 19782
      This did *not* crash any front-ends, so the corner station models have stayed up all day, and were otherwise unaffected by the rest of maintenance. This was a huge relief.

08:00 Richard and Fil continue moving GPS Antennae on roof, no further impact on the timing system
     Hugh and Jim W begin ramping down HEPI for pump maintenance
     Jim B heads down to EY to begin timing fanout replacement and SUS fast front-end BIOS upgrade

09:15 Begin corner station SEI / SUS and IMC recovery
     A little bit of trouble bringing the IMC up because the WFS output had not been offloaded in a while, so with the initial alignment the WFS trigger PD had a little bit too low of light. We've since offloaded the IMC WFS DC values to the alignment sliders to alleviate this, LHO aLOG 19814 
     HEPI HAM2 trips during recovery, HAM5 has he usual problems with Rogue Excitation vs. Watchdog RESET, but otherwise a smooth restart of the remaining SEI and SUS.
     Vinny starts PEM sensor calibrations. 

09:30 IMC recovery complete
      Jim's finished with EY Timing fanout and SUS fast FE, find that the BIOS upgrade makes no difference to ADC Timing Errors, but moves on to EX.
      Cable runs for PEM cosmic ray detector begin. LHO aLOG 19804

10:00 Betsy and Jeff begin EY SUS ETMY's RCG upgrade to get all improvements to TrueRMS and SDF sort-on-substring, discover that branch 2.9 (which has all improvements to TrueRMS) has some terrible BURT/SDF restore bug. End result is to compile against RCG 2.9.5 LHO aLOG 19793
      Hugh and Jim finish repair of HEPI pump station, and it's brought back in loop. LHO aLOG 19794

10:15 TCSX Laser trips from PEM cable pulling, recovered shortly after by Nutisnee. Ha! We knew to expect this one! LHO aLOG 19786

10:30 Huh discovers EY HEPI fluid level is significantly lower than last week, suspects accumulator bladder has let in fluid. Executive decision is to wait until next week to assess and repair. LHO aLOG 19796.
      EY HEPI Trips
      Fil and Andres head to EX to being LVLN ESD driver install and cable pulling. The new ETMX ESD LVLN Driver was literally, merely installed in the rack, but has not been hooked up. LHO aLOG 19803

11:00 Discover that EY SUS has IOP DAC output issues after finished of recompilation against RCG 2.9.5, requires full front-end shut down and restart (including TMSX and new EXPI model) LHO aLOG 19793
      Jim B. is done with BIOS upgrade for EX SUS fast-front end. Also no improvement in timing errors.

11:15 EY front-end model recovery complete
      EY SEI / SUS restoration begins
      SEI system up and running, SUS restared to damping and aligned, charge measurements begun to assess health.

11:20 EX front end model restoration begins, encountering the same problems with no IOP DAC outputs. Restart entire front-end, like EY.
      Begin EX SEI / SUS restoration begins 
      Charge measurements on ETMY ESD complete, confirm charge is OK and little no change in charge since yesterday LHO aLOG 19764
      EY recovery complete.

11:40 ISC EX and ISC EY front-end epics settings restored to 05:00
      SUSAUX model updates installed, having been compiled against RCG 2.9.5 LHO aLOG 19780      
      Preventative maintenance reboots begin
            Conlog computer restarted, no problems LHO aLOG 19789

12:00 MX / MY PEM model changes installed LHO aLOG 19809

12:10 DAQ / Frame Builder restart, doesn't come back gracefully, needs a lot of prodding from Jim and Dave. 

12:20 Frontend network switch restarted, does not fix EPICs slowdown issue
      EPICs Gateway restarted, does not fix EPICs slowdown issue
      Hardware injection machines turned OFF, does not fix EPICs slowdown issue

12:45 Guardian machine restarted. Doesn't come back up on first try, does better the second time LHO aLOG 19812
      Attempt to begin ETMX charge measurements to confirm health, but EX Beckhoff PLCs crash, not necessarily unexpectedly. After restoration, settings are restored to 05:00
      Beckhoff crash trips ETMX ESD HV Driver power supplies, and renders Beckhoff remote restart useless. 

13:00 Fil drives to end station to turn ESD power supplies back ON.

13:15 Charge measurements on ETMX ESD begin, only one data point, but confirms EX ESD is functional
      EY recovery complete
      Begin Full IFO Recovery

13:45 Initial alignment complete for green and PRM. recovery up to this point was MUCH more smooth this week

14:00 Discover that certain visiting commissioners have removed vital MICH and SRCL lock acquisition filters last night. Filters restored from archive, and we move on.

14:20 Initial alignment complete for IFO
      Begin lock acquisition sequence

14:50 Reach DC Readout, increase to high power, but lose lock instantly upon transition from ETMX to ETMY as DARM actuator

      An ETMY ISI trip, later associated with IPC communication problems because of ADC timing issues from SUS front-end. LHO aLOG 19808, LHO aLOG 19799
      several more lock-losses, a few on transition to TR CARM, a few more on transition to ETMY

16:45 Discover that certain visiting commissioners have left the ETMY hierarchical control filters in a half-commissioned state last night. Filters restored from archive.

17:00 Frame builder crashes again. LHO aLOG 19811.
      Evan notices that Trans QPD dark noise for X arm is huge. While the IFO continues to lose lock on TR CARM transition, Evan and Shiela investigate what possible QPD offset settings might have been lost.

18:00 Shiela just gives up, assumes that the dark noise of the QPDs has actually changed (perhaps because of ETMX electronics work earlier in the day)

19:40 Full IFO recovered to a stable 60 [Mpc]!
H1 CDS
sheila.dwyer@LIGO.ORG - posted 19:34, Tuesday 21 July 2015 (19815)
new one for me
Images attached to this report
H1 IOO (ISC, SUS)
jeffrey.kissel@LIGO.ORG - posted 19:18, Tuesday 21 July 2015 - last comment - 09:05, Wednesday 22 July 2015(19814)
IMC WFS Offloaded to MC Optics' Alignment Offsets
J. Kissel, K. Izumi, J. Driggers

This morning, we had a little trouble relocking the IMC because the initial alignment of the IMC SUS causes the light on the IMC WFS trigger PD to be just a hair too low. To solve the problem this morning, Jenne temporary decreased the trigger threshold (H1:IMC-IMC_TRIGGER_THRESH_ON) from 40 to 15 [ct], such that the IMC WFS engaged, which steered the IMC to our known good alignment (and then restored the trigger threshold once the WFS had steered the optics back to a good enough alignment that the normal trigger threshold was easily surpassed). To avoid this in the future, we said "we should offload the DC value of IMC WFS control signal to the MC SUS alignment offsets," but at the time didn't know that was the right script / button / thing to call in order to do so since there have been many in the past which had suffered from bit rot. 

Just now, in between lock attempts, I've asked Kiwamu what the right script is, he should me, and I ran it. This changed the alignment offsets as follows:
                                     Before             After
H1:SUS-MC1_M1_OPTICALIGN_P_OFFSET     1207.50       1208.3750756649936
H1:SUS-MC1_M1_OPTICALIGN_Y_OFFSET    -2025.30      -2024.9455029701996 	
H1:SUS-MC2_M1_OPTICALIGN_P_OFFSET      527.00        525.7250127471385
H1:SUS-MC2_M1_OPTICALIGN_Y_OFFSET     -534.03       -535.7085973743652
H1:SUS-MC3_M1_OPTICALIGN_P_OFFSET     -722.14       -721.3522559898023
H1:SUS-MC3_M1_OPTICALIGN_Y_OFFSET    -2034.10      -2034.4394052459747
I've spoken with Kiwamu about the seeminly-now-prolific issue of using double-precision python scripts to produce calculated EPICs settings to ridiculous precision, and he agreed to fix it in due time.

The script that does the offloading is launched from the IMC WFS MASTER screen, from the bright blue button marked "! OFFLOAD WFS" just below the output filters in the middle-bottom right. See attached screenshot.
Images attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 21:55, Tuesday 21 July 2015 (19820)

This alog doesn't really state it, but I assume the PZT is off loaded as well. I also assume each TM is off loaded individually.

  • Are you sure that running this script repeatedly will minimize long term drifts?
  • What keeps the uncontrolled dof in the IMC from walking away?
  • Have we established that the quads are a better long term reference than the suspensions?
kiwamu.izumi@LIGO.ORG - 09:05, Wednesday 22 July 2015 (19829)

Daniel,

  1. The offload script includes the PZT as well, as you guessed.
  2. The script does not fix long-term drift. Running the script before you hit a potential risk of loosing the ASC control values is good for speeing up relocking.
  3. I don't know what introduces drift to the uncontrolled dof. For some reason the uncontrolled dof tends to shift when some computers reboot.
  4. We don't know if the QPDs are more stable references than the suspensions. In the current configuration, the beam poointing to the interferometer is determined by a combination of a QPD (= MC2 trans) and suspensions (MC1, 2, 3 and IM1,2,3 and 4).
H1 CDS
david.barker@LIGO.ORG - posted 18:02, Tuesday 21 July 2015 - last comment - 18:27, Tuesday 21 July 2015(19809)
CDS maintenance summary

Timing Upgrades [WP5370]

Richard, Filiberto, Andres, Jim, Dave:

The timing source for the MSR timing master was transitioned from internal GPS receiver to external 1PPS. The transition went smoothly. The broken timing fanout at EY was replaced with a spare. The timing MEDM screen is now GREEN with no errors.

BIOS changes of end station SUS front end computers [WP5374]

Jim:

The BIOS settings for h1susex and h1susey were modified to be identical to the LLO computers. This was an attempt to clear the IOP glitching seen since the faster computers were installed last Tuesday, it did not clear the glitching.

RCG upgrade of end station SUS and OAF [WP5372]

Jeff, Betsy, Jim, Dave:

the h1susetmy and h1susetmypi models were built against RCG branch-2.9 to install the TrueRMS fix. We found an EPICS initialization problem and reverted the models back to RCG-2.9.5. Rolf has found the error so we can try this upgrade again.

New h1susetmxpi model [WP5365]

Dave, Jim:

the first roll-out of the h1susetmxpi model was made. To remove the "DAQ too small" error and the writing of channels to the commissioning frame which were not needed, I removed all DAQ Channels definitions in PI_MASTER.mdl. At this point the RCG chose two fast channels and set them to "acquire=0" in the ini file. This solves the problem without writing data at 64kHz to the frame. I applied this change to both h1susetmypi and h1susetmxpi

Add Beam Tube Accelerometers to PEM mid stations [WP5375]

Robert, Vinny, Dave:

the models h1pemmx and h1pemmy were modified to change the 11th ADC channel from a generic input to the BEAMTUBE_CRYO acceleromter channel. They were added to the science frame at 2kHz.

MSR Front end Rack Network Switch Reboot [WP5371]

Jim:

As part of the FE channel access problem investigation, the Netgear switch which supplies the FE-VLAN to the front end computers, boot, build and guardian was rebooted. The downtime was about a minute and all systems reconnected seamlessly afterwards. It does not appear to have fixed the problem.

MX PEM power supply failure

Jim, Dave, Richard, Filiberto:

While restarting h1pemmx models I noticed the ADC data was zero, starting around 9pm Friday 17th July PDT. We found the -18V power supply to be off. We replaced it with a spare and the AA chassis is now operating correctly.

Server reboots

Patrick, Dave, Jim

The following servers were rebooted as part of preventative maintenance: all conlog machines, h1guardian0, cdsegwe0, h1hwinj0, h1hwinj1.

after the first reboot of h1guardian0 the guardian nodes did not auto start. After a second reboot guardian started correctly.

Comments related to this report
jeffrey.kissel@LIGO.ORG - 18:27, Tuesday 21 July 2015 (19812)
J. Kissel, D. Barker

I'll call special attention to the failure of the guardian machine: after an initial restart of the guardian machine, all guardians hung white for some time. After a few minutes of wonder, we went back to Dave, who briefly took a look at [[some error log message]] that had said [[something to the affect of]] "tmpfs: bad mount on user code." A second restart of the guardian machine cleared the error it came up just Dandy. Just giving a heads up to Jamie to see if there is further investigation warranted.
H1 General
nutsinee.kijbunchoo@LIGO.ORG - posted 17:52, Tuesday 21 July 2015 - last comment - 21:48, Tuesday 21 July 2015(19806)
Tuesday Relocking Notes: Problems and Lessons learned

Travis, Nutsinee, Jeff K., Betsy, Ed, Cheryl, Hugh, Jim, Stefan, Sheila, Elli, pretty much everyone in the control room!

 

This log is meant for fellow operators, but commissioners might find it useful as well.

- We started relocking in the afternoon. Locking green went well. There was an argument about whether to request LOCKED NO SLOW or LOCKED WITH SLOW FEEDBACK (as stated in the Initial Alignment Wiki). I went for LOCKED NO SLOW because I knew it worked two Saturdays ago but I didn't know when was the last time wiki got updated (and I also don't know what LOCKED WITH SLOW FEEDBACK was). It is a good idea for the person who's maintaining the Ops wiki to put in the date and the content that was being updated (this was already brought up by TJ, but I just wanted to emphasize how important it is if we are going to use the wiki as the reference so we know we can trust it). 

- Everything went well up until MICH DARK LOCKED. The counts on the BS output were awfully high and the AS port wouldn't go dark. The solution to this in a normal situation would be to request DOWN and wait until the beam splitter becomes settle. However, Stefan found that there was a change in the LSC MICH filter and the Guardian tried to turn on the filter that no longer existed (Guradian turning on a blank filter wasn't a problem, the problem was a filter was supposed to be there). He reverted the filter to the way it was the night before. Then everything worked again. I wasn't sure if this difference showed up in the SDF or not.

- Mode Hopping! Soon as you approach DRMI LOCKED, get the IFO_ALIGN window ready. You will have to touch the beam splitter if the RF18 (pink) is low. You have to act quick! Or the interferometer will give up on you. Use AS port camera as a reference for pitch/yaw and watch "pink" and "purple" to see if you go the right way.

- We lost lock at LOW NOISE ESD ETMY. After that we had difficulty relocking ETMY green. Power dropped after WFS was engaged. Shortly after Travis found that the TMSY slide bar was off from Kissel's screenshot in the morning (or last night?). After we put TMSY yaw back to where it was and the arm was able to lock in green. Not only the screenshot never hurt, but it has also proven to be helpful! 

- We also switched ISI Windy Blend filters on for ALL Quads because the wind was reaching 35 mph (and we thought might have lost lock because of that). However, TURNING ON WINDY BLENDS TRIPPED BOTH ETMX AND ETMY ISI. Jeff demands all ISI filters are set the same while Sheila thinks it's okay to leave the Windy blend at the corner station on. Personally I would turn on the corner station windy blends iff I'm desperate. Since the wind wasn't too bad we switched the filters back to "Quite" (I'm sure it should spelled "Quiet"). This configuration worked fine the night before.

- Then we lost lock at LOW NOISE ESD agian. At least we got all the way there right after maintenance period!

- Ed was updating the Wiki during the relocking. It should be as up-to-date as it possibly can right now.

Comments related to this report
daniel.sigg@LIGO.ORG - 21:48, Tuesday 21 July 2015 (19819)

LOCKED NO SLOW: no tidal relief

LOCKED WITH SLOW FEEDBACK: tidal is feed to the ETM (will keep the green laser frequency constant)

It makes little difference, if you only spend a small amount of time in this mode. On the other hand, I am not aware of any reason why LOCKED WITH SLOW FEEDBACK wouldn't be the better option under any circumstances.

H1 AOS (CAL)
darkhan.tuyenbayev@LIGO.ORG - posted 13:20, Tuesday 21 July 2015 - last comment - 11:43, Wednesday 22 July 2015(19792)
Adjusted calibration line drive levels

RickS, Sudarshan, Darkhan

We've adjusted PCALX, PCALY and ESD calibration line drive levels to give a signal to noise ratio of about 100 (for 8 s FFT) over the mean science mode spectra from ER7.

The following lines have been adjusted:

Line Frequency (Hz) Old drive level (ct) New drive level (ct)
PCALX 33.1 38 700
PCALX 534.7 6000 19300
PCALY 36.7 40 320
PCALY 540.7 5000 9900
ESD 34.7 0.50 0.22
ESD 538.1 0.20 2.40
Comments related to this report
evan.hall@LIGO.ORG - 02:28, Wednesday 22 July 2015 (19823)CAL

I added pcal lines at 325.1 Hz, 3000 ct for X and 331.9 Hz, 1500 ct for Y. These are maybe not optimal because they are in the region of the PSL piezo mirror mount, but I wanted to stay close to the DARM pole and out of the bottom of the bucket.

darkhan.tuyenbayev@LIGO.ORG - 11:10, Wednesday 22 July 2015 (19837)

Based on noise levels around calibration lines during ER7, to get SNR of 100 (with 8 s FFT) , drive levels adjustments needed for LLO calibration lines:

    PCALX_TX_at_33_7_Hz should be increased 6.19 times;
    PCALX_TX_at_533_3_Hz should be increased 3.19 times;
    PCALY_TX_at_37_3_Hz should be increased 6.41 times;
    PCALY_TX_at_539_9_Hz should be increased 4.42 times;
    LINE_SUM_at_34_9_Hz should be increased 1.68 times;
    LINE_SUM_at_535_1_Hz should be increased 1.51 times.
kiwamu.izumi@LIGO.ORG - 11:43, Wednesday 22 July 2015 (19839)

I inserted a nototch filter for each of the two lines that Evan added last night. Because of the limitation in the number of the IIR coefficients, I had to put one in suscomp (in FM7) and the other in ResG (in FM3). The previous notch that we put for the cavity pole tracker (alog 18401) was removed from FM7 since we have not been using it.

H1 ISC (DetChar, ISC)
hang.yu@LIGO.ORG - posted 02:07, Tuesday 21 July 2015 - last comment - 20:07, Tuesday 21 July 2015(19773)
HAM5 vs DARM
Rana, Matt, Hang

We did some further investigation of HAM5's coherence with DARM, as suggested by Gabriele (aLog # 19756). A list of what we did:

05:35:10 (UTC): Tapped the lower middle flange south of HAM5. 
05:35:32 (UTC); Tapped the same flange harder.
05:35:54 (UTC): Tapped gull wing. The interferometer lost lock. Before the unlock, the IFO was operating at 24 W with LSC FF on.

A plot of the corresponded time series was attached (TSaccHam5vsDarm.png). We could see ringing corresponding to tapping the flange in HAM5 channel, yet they did not seem to have a significant effect on DARM.  The frequency of the ringing was 207Hz with a decay time of 1.6s. No 90 Hz feature seen. The gull wing tapping did not appear in the ACC_HAM5_SR1 that Gabriele noted.  Summary: no clear connection between this ACC and DARM.
Images attached to this report
Comments related to this report
rana.adhikari@LIGO.ORG - 04:21, Tuesday 21 July 2015 (19776)

evan, rana

we did further slapping and shouting around HAM5/6 (from 10:25 - 10:39 UTC) and saw a few interesting things:

  1. rapping on the chamber doors (HAM5 / 6) made no noticeable change in the DARM spectrum
  2. brushing the pink clean room curtains produces no issues, except...
  3. many of the curtains are touching the HEPIs; touching these ones produce broadband glitches in DARM, presumably through some L4-C saturations
  4. the piece of beamtube between HAM5 and where the tube gets fat is in two pieces; the one with bellows on both ends has low frequency modes from 90-100 Hz. These are easily visible in DARM with gentle tapping. Not sure if this is related to the 90 Hz coherence seen in BruCo.

afterwards, we ran Hang's A2L script. It ran well, but takes awhile. We ought to run these in parallel.

rana.adhikari@LIGO.ORG - 20:07, Tuesday 21 July 2015 (19816)DetChar, ISC

Some times and events for analysis:

10:25:45     knocking on HAM5-south

10:26:01      knock on south door, upper west side

10:26:40      wiggle HAM5's curtains

10:27:40      wiggle HAM6's curtains

10:27:53      acoustic injection near HAM6 east side

10:28:12     ISCT6 acoustic noise

10:28:46     HAM5 north door

10:30:22     HAM5-HAM4 manifold

10:32:32     septum plate (north end)

10:34:39     HAM4-5 manifold whack

10:35:45     tube between bellows near HAM5

10:37:34     more of same

10:38:14     more of same

 

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