Displaying reports 53881-53900 of 83228.Go to page Start 2691 2692 2693 2694 2695 2696 2697 2698 2699 End
Reports until 10:29, Monday 03 October 2016
H1 TCS (TCS)
vernon.sandberg@LIGO.ORG - posted 10:29, Monday 03 October 2016 - last comment - 12:13, Monday 03 October 2016(30170)
TCS Chiller Status and Fill Report

Gerardo and Vern

TCS-X: Full no water added, 3.9 gal/min, 20.0 deg C.

TCS-Y: found water level to be 6.6, added 750 mL to raise gauge to 8.6, 4.0 gal/min, 19.8 deg. C.  Unusual fill pattern, first 500 mL showed no sign on gauge then suddenly the gauge ball droped to 5.0 and climbed with the addition of the last 250 mL of water.

Noticed the icons on the two chiller control panels were different. TCS-X displayed horizontal bars. TCS-Y displayed chevrons pointing up. 

Comments related to this report
betsy.weaver@LIGO.ORG - 10:40, Monday 03 October 2016 (30171)

I'm guessing that the TCS-Y symbols are related to the fact that this laser tripped right when you guys were refilling the water for some reason (9:45am).

matthew.heintze@LIGO.ORG - 10:47, Monday 03 October 2016 (30172)

Yes this is normal. Means that the chiller is heating with the arrows pointing up (or cooling when pointing down) so that the water is at the setpoint of the chiller

cheryl.vorvick@LIGO.ORG - 11:03, Monday 03 October 2016 (30173)TCS

At Richard's request, I inspected the inside of both TCS tables, and found nothing, no drips and no sign of water, the tables are dry.

I inspected TCSY first, then TCSX.

betsy.weaver@LIGO.ORG - 11:06, Monday 03 October 2016 (30175)

Also, apparently both Gerardo and I, separately, walked the length of the piping and found no leaks.

 

Attached is this morning's story of laser power.

Images attached to this comment
alastair.heptonstall@LIGO.ORG - 11:36, Monday 03 October 2016 (30177)

It looks like there is a small increase in temperature on the laser which causes a power output increase from the laser.  Following that the laser trips off, and the Guardian code then starts trying to relock the laser.  

We'll need to  think about the right way to get Guardian to "see" that the laser has tripped off - we should get it to check the laser error channels.  Anyway that's why the temperature of the chiller has those steps in it.

I'm not sure how sensibly Guardian will react if you just restart the laser without restarting Guardian.  The reason I say this is because it typically takes ~30mins for the laser to come into thermal equilibrium during which time Guardian won't be able to lock it.  Also while Guardian is hunting for a locking point it will occasionally be stepping the chiller temperature (as shown in the chart) which may in turn increase the time taken for the laser to reach an equilibrium temperature.  This logic isn't well baked in to the current Guardian code which at the moment locks the laser when it is reasonably stable (ie after 30mins of running unlocked).

betsy.weaver@LIGO.ORG - 11:58, Monday 03 October 2016 (30179)

I'm thinking the anomolous note Vern mentions in the first post on this thread is the culprit for the laser trip:  The indicator float bobbled way low and then rose while they were filling.  So, I think an air bubble pushed out from under the filter and dropped the level briefly, thus triggering a low water level trip.

 

This adds to my thought that maybe the mystery water "loss" issue is actually not a water loss at all, but an air loss.  Maybe we didn't fill the chiller all the way up when we found the chiller dry on Wed, and we are still "topping it off'.  as I pointed out last week, the indicator goes/stays low after you push air out from under the filter.  Today, I played with this more and was again able to bleed more air out from under the puffy filter fabric which then left the indicator low.  I had to fill another 225mL just in playing with it.  Attached are pix of the X and Y filter while water is running thru.  Note how the Y filter fabric is being pushed up towards the surface of the water, while the X one has more of a trough down the middle?  (Use your imagination, it is much more obvious when standing over it and pushing it around with a gloved hand or hose tool). 

 

They added 1.3gal (5L) on Wed when they found it dry.  We've added ~a gallon (3800mL) since then, in small ~500mL batches.  I'm looking up the capacity of the chiller...

Images attached to this comment
betsy.weaver@LIGO.ORG - 12:13, Monday 03 October 2016 (30181)

The chiller reservoir volume is listed as 7.2L (1.9 gal).

We've added ~5L plus ~3L since Wed - given some error bar on these plus a little reasonable amount of bubble bleeding, we might find that the indicator reading settles out at "full".  That's one theory anyways...

We have inspected the tables, the piping and the chillers 3 times since last Tues and cannot find any loss of water.

H1 CDS
james.batch@LIGO.ORG - posted 09:32, Monday 03 October 2016 (30167)
Restarted h1lsc0 after replacing bad power switch
WP 6179
F. Clara, J Batch

The rear panel power switch for the I/O chassis for h1lsc0 was replaced this morning, the h1lsc0 computer has been restarted.
LHO General
patrick.thomas@LIGO.ORG - posted 08:55, Monday 03 October 2016 (30166)
Morning meeting notes
* First 4 hours of today declared maintenance *

SEI: Tue: Investigate elevated CPS noise on BSCs. Power cycling boards, etc. Takes ISIs down.
PSL: Separate breakout meeting before commissioning meeting to address periodic tripping off of PSL.
TCS: Possible water problem on TCSY. Check table today before going laser safe tomorrow.
VAC/FAC: Tue: Crane scissor lift. Request for laser safe Tue.
CDS: Fix bad pin on AS-C QPD whitening chassis.

Photographer for Science magazine back tonight
Jeff B.: Check all dust monitors on site (time permitting)
H1 AOS (PSL)
robert.schofield@LIGO.ORG - posted 16:17, Sunday 02 October 2016 (30164)
Strange behavior of power meter flow sensor

I attach a plot showing several flow sensors and flags around the time of the latest PSL shutdown. The power meter flow sensor channel (thought to be responsible for the shutdown) has a strange constant oscillation that does not stop when the flow does,  and it doesnt go to zero. It doesnt seem consistent with an air bubble shutdown and may need replacement or there may be problems with the data acquisition.

Non-image files attached to this report
LHO General
corey.gray@LIGO.ORG - posted 15:33, Sunday 02 October 2016 (30152)
Ops Day Shift Summary

TITLE: 10/02 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: DOWN due to PSL
INCOMING OPERATOR: Corey
SHIFT SUMMARY:

The PSL continued to have issues today & decided to cancel EVE & OWL shifts tonight.  Did make it to NLN twice (PSL trip ended both) which is nice (ITMy Bounce must be gone).  

LOG:

H1 PSL
corey.gray@LIGO.ORG - posted 14:34, Sunday 02 October 2016 (30161)
CANCELING EVE & OWL Shifts Tonight

With the PSL only able to operate for an hour or so at a time, it was decided to work on the PSL TOMORROW and cancel the EVE & OWL shifts.  (Jason consulted with Vern & I've been in contact with Daniel, Mike, & Vern via email.)

H1 PSL (PSL)
corey.gray@LIGO.ORG - posted 14:03, Sunday 02 October 2016 (30160)
2:01pm Another PSL Trip (after ~40min of NLN)

Was just getting ready to post an alog saying we've been in NLN near 60Mpc and that Robert was going to do injections, but the PSL tripped as I opened the alog....going to call Jason...after I have lunch.

H1 PSL
corey.gray@LIGO.ORG - posted 12:24, Sunday 02 October 2016 - last comment - 12:52, Sunday 02 October 2016(30154)
12:16pm: 15min at NLN, Then PSL Trips.

15min at NLN, here are notes on DARM:

Comments related to this report
corey.gray@LIGO.ORG - 12:52, Sunday 02 October 2016 (30156)

Completed Recovery in ~30min with Jason on the phone.  Back to locking at 12:42pm.

NOTE:  LRA, stands for Long Range Actuator.

H1 PSL (OpsInfo, PSL)
corey.gray@LIGO.ORG - posted 10:52, Sunday 02 October 2016 - last comment - 10:50, Friday 07 October 2016(30150)
PSL Recovery From Flow Sensor Trip (and Being down/cold for 10+hrs)

(Corey, Jason on phone)

Last night, Nutsinee came in early for her OWL shift & just before midnight the PSL tripped.  We opted to leave it tripped for the night to wait for Jason to walk us through recovery procedure.  Atleast for now, we always want to run through this procedure with one of our PSL people (Jason or Peter K).  Here are my rough notes:

Now on to "Aligning" on Observatory Mode!

PSL Status NOTE:

Comments related to this report
dennis.coyne@LIGO.ORG - 12:21, Sunday 02 October 2016 (30153)

The Xtal chiller has tripped 3 times in the last week:

  • 9/25 (29964) - added 200 mL water - "normal due to known slow leak"

then 4 days later:

  • 9/29 (30063) - added a "few 100 mL" water - water sprayed onto door

now 3 days later:

  • 10/2 (30150) - "cap blew off" - added 375 mL

The last two events imply an overpressure condition. The problem seems more significant than replacing lost fluid from a slow leak.

Was the cap which "blew off" in today's event the "bleeding cap" (section 4.2.2), the "filter sleeve cap" (section 6.2) or the "filler pipe cap" (section 6.3 of T1100374-v1, "200 W Laser Crystal Chiller Manual")?

 

BTW, LRA = Long Range Actuator; see section 7.2 of  T0900641-v5, "Under Manual 200 W Laser".

matthew.heintze@LIGO.ORG - 12:51, Sunday 02 October 2016 (30155)PSL

From my quick look through the alog I think the PSL has tripped more than this (for LHO to concur). From what I can see it has gone off 11 times in the last week (thats as far as I looked back).

 

I'm not sure if all the same problems, but alogs reporting the PSL laser off are LHO alogs:

10/2/2016

LHO alog 30160

LHO alog 30154

10/1/2016

LHO alog 30146

LHO alog 30143

9/30/2016

LHO alog 30118

LHO alog 30086  (due to power glitch)

9/29/2016

LHO alog 30076

LHO alog 30063 (this alog reports two different  instances of the laser going off)

9/27/2016

LHO alog 30016

9/25/2016

LHO alog 29964

 

The filler pipe cap popping out is a known thing (happens all the time at LLO) when the chiller turns OFF. At LLO at least this has not shown to be due to any problem (just a consequence for whatever reason when the chiller is turned off).  Its why we try to not turn these chillers OFF if can help it as they "burp" water over the floor and pop these fill caps even when trying to restart

 

I have as one of the main agenda items of this Wednesdays PSL meeting to discuss this problem and see if we can work out whats going on. Some statistics on how many times happened in say the last month or two, what the PSL trip was attributed to, and how many times happened before and after the chiller swap (to see if accelerating or at the same rate), would help this. Im not sure if FRS fault reports have been made for each laser trip to make this search easy for us remote to the site to do and work out how much lost observatory time we have had due to this issue.

corey.gray@LIGO.ORG - 12:58, Sunday 02 October 2016 (30157)PSL

Yes, Dennis, as Matt says it's the Filler Pipe Cap that pops off.  We have had (3) trips since Friday evening (so Matt is probably right about there being more trips over the whole week).  OH, and I should correct ourselves here because we just had a 4th Weekend PSL trip (this was just after I had H1 at NLN for 15min.  This time the cap was blown off and there was a puddle on the floor.

Able to get back in 30min this time (vs 60min this morning).

OK, back to locking.  

corey.gray@LIGO.ORG - 13:42, Sunday 02 October 2016 (30158)

Another Note:

Something I wanted to add about the chiller was that when filling it, I noticed quite a bit of turbulence in the fill pipe.  And you could see a air bubble vortex/tornado in there.  Something we probably don't want if air bubbles are postulated as a trigger for flow sensor trips.  

matthew.heintze@LIGO.ORG - 13:48, Sunday 02 October 2016 (30159)

We see these bubbles as well in the chiller fill pipe at LLO with no chiller trips due to it (hopefully haven't jinxed myself). Perhaps post a movie of it so can see if looks the same as here

corey.gray@LIGO.ORG - 14:49, Sunday 02 October 2016 (30163)

Jason & crew will be investigaing tomorrow.  We should ask them to record a video of it.

matthew.heintze@LIGO.ORG - 05:21, Monday 03 October 2016 (30165)

Movie of the water turbulence of LLO's crystal chiller fill tube posted at LLO alog 28397

jason.oberling@LIGO.ORG - 10:50, Friday 07 October 2016 (30304)

I took a video, but I can't post it; my phone only takes video in .mp4 format, which is apparently not a valid file type for upload to the alog.  Huh.

I attached a still from the video to give you some idea of what we've been seeing here for the last few weeks.  It's appearing to fluctuate though; the video was taken on Monday, 10/3/2016, but this morning our fill port looks very similar to what's seen in Matt's video of the LLO crystal chiller fill port.

Images attached to this comment
H1 ISC
stefan.ballmer@LIGO.ORG - posted 21:21, Friday 30 September 2016 - last comment - 20:58, Monday 03 October 2016(30126)
Input beam Gouy Phase (for jitter investigations)

In an attempt to bring some clarity into the beam jitter discussion I looked at the Gouy phase evolution of the input beam. I collected distance and focal length information from a variety of sources, notably T1200470 and E1200616.

The biggest uncertainty I had was the PSL persicope to HAM1 viewport distance - if someone knows that, let me know.

The MATLAB script with all the numbers is in ~controls/sballmer/20160930/inputBeamCalc.m. It creates a structure of the following form, fully describing the beam and optical mode:

IMC =
    lambda: 1.0640e-06               % The wavelength in m
         q: 0.2325 +13.3832i          % The input Gaussian beam parameter q=z+izR in m
         N: 4                                 % number of optics
      dist: [16.2406 16.2406 0.2325 0.2325 0] % Distances between the optics (one more than N)
      ifoc: [0.0731 0 0 0]               % inverse focal length for all lenses and mirrors (f=R/2 for mirror)
     label: {'MC2'  'MC3'  'Waist'  'MC1'} % optic names
 

The attached .mat file contains the following structures of that form::

IMP:    Input beam: From PSL periscope to MC3
IMC:    Input Mode Cleaner
IMCp:  Input Mode Cleaner from MC1 to MC3 only (output path inside IMC)
IM:      Input Mirros: from IMC to PRM
PRC:  Power Recycling Cavity forward path
PRCr: Power Recycling Cavity return path
PRCrt:Power Recycling Cavity round trip

Below are plots and data for the different beam segments.

Non-image files attached to this report
Comments related to this report
stefan.ballmer@LIGO.ORG - 20:52, Friday 30 September 2016 (30127)

Input Mode Cleaner:

IMC =
    lambda: 1.0640e-06
         q: 0.2325 +13.3832i
         N: 4
      dist: [16.2406 16.2406 0.2325 0.2325 0]
      ifoc: [0.0731 0 0 0]
     label: {'MC2'  'MC3'  'Waist'  'MC1'}
       Pin: 50

z= 00.0000 m, Gouy phase: 00.0000 deg after passing MC1;   Spot size w=2.1293 mm
z= 16.2406 m, Gouy phase: 49.9133 deg after passing MC2;   Spot size w=3.3764 mm
z= 32.4812 m, Gouy phase: 99.8267 deg after passing MC3;   Spot size w=2.1293 mm
z= 32.7137 m, Gouy phase: 100.822 deg after passing Waist; Spot size w=2.129 mm
z= 32.9462 m, Gouy phase: 101.8172 deg after passing MC1; Spot size w=2.1293 mm
Round trip Gouy phase:  101.8172 deg

Gouy Phase from input coupler (MC1) to output coupler (MC3): 99.8267 deg

Images attached to this comment
stefan.ballmer@LIGO.ORG - 21:02, Friday 30 September 2016 (30128)

Input mirrors: From PSL periscope to MC3:

IM =
    lambda: 1.0640e-06
         q: -0.2325 +13.3832i
         N: 6
      dist: [0.2325 0.5507 1.0613 1.1703 1.2071 0.4130 0]
      ifoc: [0 0 0.1562 -0.3199 0 0.0409]
     label: {'Waist'  'IM1'  'IM2'  'IM3'  'IM4'  'PRMlens'}

z= 0.0000 m, Gouy phase: 0.0000 deg after passing MC3;         Spot size w=2.1293 mm
z= 0.2325 m, Gouy phase: 0.99527 deg after passing Waist;      Spot size w=2.129 mm
z= 0.78319 m, Gouy phase: 3.3516 deg after passing IM1;         Spot size w=2.1308 mm
z= 1.8445 m, Gouy phase: 7.8634 deg after passing IM2;           Spot size w=2.1444 mm
z= 3.0148 m, Gouy phase: 13.8099 deg after passing IM3;         Spot size w=1.7841 mm
z= 4.2219 m, Gouy phase: 19.9983 deg after passing IM4;         Spot size w=2.1257 mm
z= 4.6349 m, Gouy phase: 21.6763 deg after passing PRMlens; Spot size w=2.2471 mm
 

Images attached to this comment
stefan.ballmer@LIGO.ORG - 21:10, Friday 30 September 2016 (30129)

Input beam: From PSL periscope to MC3:

(The PSL periscope to input viewport distance is an educated guess.)

INP =
    lambda: 1.0640e-06
         q: -7.3931 +13.3832i
         N: 6
      dist: [0 2.7100 4.0180 0.2118 0.1400 0.2563 0.2895]
      ifoc: [0 0 0 0 0 0]
     label: {'PSLperiscope'  'INPUTViewPort'  'PeriscopeTop'  'PeriscopeBottom'  'Steer1'  'Steer2'}
 

z= 0 m, Gouy phase: 0 deg after passing PSLperiscope;                       Spot size w=2.4323 mm
z= 2.71 m, Gouy phase: 9.6308 deg after passing INPUTViewPort;         Spot size w=2.2556 mm
z= 6.728 m, Gouy phase: 26.0719 deg after passing PeriscopeTop;        Spot size w=2.1316 mm
z= 6.9398 m, Gouy phase: 26.9771 deg after passing PeriscopeBottom; Spot size w=2.1302 mm
z= 7.0798 m, Gouy phase: 27.5759 deg after passing Steer1;                Spot size w=2.1296 mm
z= 7.3361 m, Gouy phase: 28.6729 deg after passing Steer2;                Spot size w=2.129 mm
 

Images attached to this comment
stefan.ballmer@LIGO.ORG - 21:15, Friday 30 September 2016 (30130)

Power Recycling Cavity:

PRCrt =
    lambda: 1.0640e-06
         q: 7.1228 + 5.2551i
         N: 8
      dist: [16.6128 16.1551 24.8880 0 0 24.8880 16.1551 16.6128 0]
      ifoc: [-0.4391 0.0556 -2.3189e-04 -0.0010 -2.3189e-04 0.0556 -0.4391 -0.1818]
     label: {'PR2'  'PR3'  'ITMlens'  'ITMback'  'ITMlensr'  'PR3r'  'PR2r'  'PRM'}

z= 00.0000 m, Gouy phase: 00.0000 deg after passing PRM;      Spot size w=2.2471 mm
z= 16.6128 m, Gouy phase: 23.9355 deg after passing PR2;       Spot size w=6.1716 mm
z= 32.7679 m, Gouy phase: 24.8769 deg after passing PR3;       Spot size w=53.9602 mm
z= 57.6559 m, Gouy phase: 25.0458 deg after passing ITMlens;  Spot size w=52.9743 mm
z= 57.6559 m, Gouy phase: 25.0458 deg after passing ITMback; Spot size w=52.9743 mm
z= 57.6559 m, Gouy phase: 25.0458 deg after passing ITMlensr; Spot size w=52.9743 mm
z= 82.5438 m, Gouy phase: 25.2148 deg after passing PR3r;      Spot size w=53.9602 mm
z= 98.6989 m, Gouy phase: 26.1562 deg after passing PR2r;      Spot size w=6.1716 mm
z= 115.3117 m, Gouy phase: 50.0916 deg after passing PRM;    Spot size w=2.2471 mm
Round trip Gouy phase: 50.0916 deg (one-way Gouy phae: 25.0458 deg)

Images attached to this comment
jeffrey.kissel@LIGO.ORG - 09:34, Monday 03 October 2016 (30168)SYS
I see you've used 2.71 [m] as your distance between the PSL periscope an the HAM1 viewport, and mentioned this was a big uncertainty.

If I take the corner station Rack/Cable tray layout D1002704, which tells the distance between the HAM1 viewport and the +X edge of the PSL table is 86 [in], and add it to the distance from the edge of the table to the periscope mirrors from D0902114 -- 14 [in] -- I get an even 100 [in].

Thus, 2.54 [m] is likely a better number.

I tag Systems just in case they have an even more accurate/precise number, but I think past the ~inch level precision, we'd need to measure it.
cheryl.vorvick@LIGO.ORG - 20:58, Monday 03 October 2016 (30196)
T1000696-v2 PSL table to HAM1 door flange 88in
T1000696-v2 HAM door depth 18in
picture top periscope mirror to edge of table 14in
total top periscope to input viewport 84in, 2.134m 

T1000696-v2 has verified distances.

D1002704 is measuring PSL table North edge to HAM1 door flange, and states it's 86 inches.

D1102219-v1, Micheal Rodruck's document, aptly named H1_table_v1.pdf, has what I believe are measured values, though not in a form that's easy to use, but what I've looked at is consistant with T1000696-v2.

Using this combination of documents, the outer PSL wall to the input viewport is calculated to be 70 inches, something that could easily be measured.

Non-image files attached to this comment
H1 ISC
daniel.sigg@LIGO.ORG - posted 17:04, Friday 30 September 2016 - last comment - 11:26, Tuesday 04 October 2016(30119)
Jitter into the IMC

This is a plot of the jitter measured by the IMC WFS DC PIT/YAW sensors during last nights lock. The 280 Hz periscope peak reaches about 1x10-4/√Hz in relative pointing noise, or about 3x10-4 rms. The relative pointing noise out of the HPO is about 2x10-5/√Hz at 300 Hz. After the attenuation through the PMC this would correspond to a level below 10-6/√Hz. The jitter peaks show up in DARM, if they are high enough. This is clearly visible in the coherence spectra.

The ISS second loop control signal is an indication of the intensity noise after the mode cleaner with only the first loop on. The flat noise level above 200 Hz is around 3x10-6/√Hz in RIN, with peaks around 240 Hz, 430 Hz, 580 Hz and 700 Hz. Comparing this to the free-running noise in alog 29778 shows this RIN level at 10^-5/√Hz. We can also compare this with the DBB measurements, such as in alog 29754: the intensity noise after the HPO shows a 1/f behaviour and no peaks. Looking at the numbers it explains the noise below 300 Hz. It looks like a flat noise at the 10^-5 level including the above peaks gets added to the free-running intensity noise after the PMC. The peaks in the controls signal of the second loop ISS line up with peaks visible in the pointing noise. But, neither the numbers nor the spectral shape matches. These peaks have coherence with DARM.

Non-image files attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 10:30, Monday 03 October 2016 (30169)

Checking the calibration of the WFS DC readouts I noticed a calibration error of a factor of 0.065. So, all angles measured by the WFSs should be scaled by this number. This still makes the jitter after the PMC dominant, but one might expect to see some of the HPO jitter peak show through in places where the downstream jitter has a valley. In any case, we should repeat the PSL jitter measurement with the IMC unlocked.

Non-image files attached to this comment
daniel.sigg@LIGO.ORG - 11:26, Tuesday 04 October 2016 (30206)

A report of the measured beam jitter at LLO is available in T1300368.

An earlier measurement at LHO is reported in alog 21212. Using an IMC divergence angle of 1.6x10–4 rad, the periscope peak at 280 Hz is around 10^-4/√Hz. This is closer to the first posted spectrum with the "wrong" calibration. Here I post this spectrum again and add the dbb measurement of the jitter out of the HPO propagated through the PMC (1.6%), but scaled by a fudge factor of 2. The Sep 11, 2015, spectrum shows a more or less flat noise level below 80 Hz, whereas the recent spectrum shows 1/f noise. The HPO spectrum also shows as 1/f dependency and is within a factor of 2 of the first posted spectrum. If jitter into the IMC is the main coupling mechanism into DARM, the HPO jitter peaks above 400 Hz are well below the PSL table jitter after the PMC and the would not show up in the DARM spectrum.

Non-image files attached to this comment
H1 ISC
nutsinee.kijbunchoo@LIGO.ORG - posted 07:04, Friday 30 September 2016 - last comment - 14:44, Sunday 02 October 2016(30085)
Adding a small offset to CSOFT gained us 15 Mpc in range

Tasked by Kiwamu and Stefan to turn random knobs in a hope of getting rid of 100-1kHz bump, I was able to gain 15 Mpc by adding -0.05 offset to CSOFT pitch and yaw. I haven't had a chance to try every ASC knobs due to the power glitch. We were at 75 Mpc before the IFO went down.

Here's a note on everything I've tried (all time in PT):

3:40 added/subtracted 0.02 counts to H1:LSC-MOD_RF45_AM_RFSET -- Nothing improved

3:46 Added +6 gain to PRC1 LSC -- 27 Hz line became visible. But later found this line to come and go so this could totally be a coincidence

3:52 Changed CO2X power to 1W -- quickly dropped the power back to nominal when I realized that it's probably going to take a while to see the result

4:38-4:58 [In ASC land] Played with CSOFT pitch and yaw offset -- Settled at -0.05 for both. Slightly improved overall DARM spectrum but made 20-30 Hz wrose. Gained 15 Mpc in range here (if it's not calibration that's fooling with me). Any more negative number added would decrease AS90/POP90.

5:06 Added -10 to CHARD pitch -- nothing improved

5:13 Added -0.07 to CSOFT pitch -- nothing improved

5:14 Added -20 offset to CHARD yaw. -- Nothing improved

5:17 Added offset to DHARD pitch -- Nothing improved

5:27 Added offset to DSOFT pitch -- Nothing

5:48 Added -0.05 offset to DSOFT yaw -- Increased AS90/POP90 but no obvious approvement in DARM.

5:58 Added -25 offset to INP1_Y -- improved AS90/POP90 but no apparent improvement in DARM spectrum

6:08 Power glitch. Meh.

 

I also moved PR3 and changed something on SRC1 but didn't write down details (since it probably was not doing anything).

I put everything back in place before the power glitch except for the CSOFT gain that worked. I turned off all the gain buttons that I turned on except for CSOFT P and Y but not neccesary return the gain number back to what they were. I have them all written down though.

Images attached to this report
Comments related to this report
nutsinee.kijbunchoo@LIGO.ORG - 14:44, Sunday 02 October 2016 (30162)
In the last paragraph I meant "offset" when I wrote "gain". Just to clarify I added -0.05 offset to CSOFT pitch and yaw. Sorry about the confusion.
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