BRSY out of commission for a few days

I went to try to recenter BRSY today, but I had little luck. Looks like it's sitting in another difficult spot. I spent 5 hrs trying to recenter and barely out of range is the best I could do. It will drift further out of range as the box heats up again. I've left the damping off on the BRS and have turned off the outputs on the sensor correction paths that use the BRS. Right now, this probably won't prevent locking, but if someone tries to turn on the sensor correction at EY it will trip the ISI, as seems to have already happened once today. I've left the outputs of the appropriate sensor correction banks off, so please talk to me before "fixing" the ETMY ISI SDF or trying to change the ISI's controls configuration. I need a day to recover enough to try again, so I'll see if I can make another attempt on Thursday.

h1seih16 timing tripped, models restarted

It looks like cabling work in the CER accidentally glitched the timing for h1seih16 (its at the end of the row of racks). I have restarted all the models on this front end computer.

Ringdown Q measurements of the 4th and 5th harmonic for the QUAD violin modes - After Earthquake

These ringdown measurements, of the LHO QUAD suspensions violin mode 4th and 5th harmonics, were obtained 2 days after the big Earthquake hitting LHO on the 20170706. For this analysis I used 17 hours of detector data in Low noise state from "20170708 06:30:00" UTC. None of the 4th and 5th harmonics were being actively damped or excited. Although clearly the Earthquake excited these harmonics well enough to get very nice ringdowns.

In this analysis, a line tracker (iWave) was applied over each of the identified 4th and 5th harmonic frequencies, locking onto them.

I give next the results for those frequencies that show ringdowns. I also attach 'png' plots which shows; in each column the mode monitored with the top plot being the frequency tracked as a function of time, the middle plot is the 'log(Amplitude)' (natural logarithm of the mode's amplitude). The red dashed lines are respectively the median of the tracked frequency and the fitted first order polynomial to the 'log' of the mode's ringdown. The plot at the bottom shows the Phase deviation respect to the linear fit.

4th Harmonic

Mode frequency (Hz)          Q  

1924.678                           795280070

1924.919                           940157702

1926.236                         1013199693

1927.462                          963907721

1929.327                          590576596

1931.569                        1022004204

1932.15                            890355597

1932.331                          985512132

1932.623                          946775350

1941.352                          838872691

1942.129                          808459376

1942.178                        1140538266

1942.384                          806784836

1946.727                        1153580301

1947.704                        1078584113

1954.459                          778605954

1956.503                          788173599

1957.333                          847485779

 

5th Harmonic

Mode frequency (Hz)          Q  

2373.487                         431860210

2374.656                         495634311

2381.893                         719623590

2382.987                         638328976

2385.441                         691971670

2386.924                         767976787

2398.523                         791021530

2398.529                         761223997

2399.509                         843982379

2400.302                         746568211

2404.642                         860932811

2405.621                         807844171

2406.763                         630423384

2407.992                         880751631

2409.266                         617892329

2410.265                         819561647

2411.371                         789591091

2414.764                         827720300

2415.259                         860571672

2419.552                         603552195

2424.416                         575422358

2427.241                         672293500

2428.109                         789905044

 

These results show that exciting and measuring the Q of higher order harmonics is possible. If we are able to identify these higher order harmonics with specific fibres then this information could be used to enhance suspension thermal noise characterisation.

Optical Lever 7 Day Trends

  The plots of the OpLev 7 day trends are attached. All look OK, except ETMX Pitch, which is approaching -10, down from 0 a week ago. Closinf FAMIS #4742

Add Water to TCS-Y

   Found the water level on TCS-Y chiller to be just above the zero level. I added 1420ml to bring up the water level up to the 3/4 level. Before today, water added was 40 days ago. TJ and Jason checked the system lines and found no apparent leaks. TJ is going to take a look on the table.  

h1fwsex to run only kernel 3.19.49

The machine h1hwsex was pinned to run kernel 3.19.49 which is the newest kernel that successfully work with the hws camera, previeusly it was trying to run 3.19.78 on boot, but we removed that option from Grub. see work permit number 7128

additional ethernet PCIe card installed in h1ecatc1

WP7127 Daniel, Dave:

we powered down h1ecatc1, installed a second ethernet PCIe card in the second slot down on the full card size side, and powered the computer back up.

h1susey BIOS change, CPU power management setting changed

WP7126: Dave:

The BIOS setting on h1susey was modifed in an attempt to stop the periodic ADC glitching seen on these faster computers. Gerrit at AEI discovered that disabling the 'turbo' cpu mode fixed the glitching.

The BIOS path to the relevant screen is Advanced -> CPU Configuration -> CPU Power Management Configuration

The 'Power Technology' item was changed from 'Max Performance' to 'Disabled'

Before this change both h1susex and h1susey were glitching (approximately several times per day), now hopefully h1susey will stop glitching.

Unfortunately, even though I manually took h1susey out of the Dolphin fabric, and ran its power off script, it still glitched the EY Dolphin on restart. All models on h1seiey and h1iscey needed to be restarted. For now on we will assume this glitching can happen and put SEI into its SAFE state before rebooting SUS.

The CPU usage of the models running on h1susey are shown in the second trend plot attached (two hour trend, BIOS change in the middle). The IOP model (Ch 3) does not show any change. SUSETMY (Ch 4) is running 2uS longer (33uS to 35uS). SUSTMSY (Ch 5) is running 1uS longer. SUSETMYPI (Ch 6) is running 1-2uS longer.

All are well within nominal range.

PSL Weekly Report

Laser Status:
SysStat is good
Front End Power is 33.8W (should be around 30 W)
HPO Output Power is 154.8W
Front End Watch is GREEN
HPO Watch is GREEN

PMC:
It has been locked 14 days, 1 hr 23 minutes (should be days/weeks)
Reflected power = 16.87Watts
Transmitted power = 57.1Watts
PowerSum = 73.97Watts.

FSS:
It has been locked for 0 days 1 hr and 12 min (should be days/weeks)
TPD[V] = 1.446V (min 0.9V)

ISS:
The diffracted power is around 3.2% (should be 3-5%)
Last saturation event was 0 days 1 hours and 12 minutes ago (should be days/weeks)

Possible Issues:

None

ETM HWS Measurements Re-Done

I decided to re-do these measurements because the previous aLOG-38213 seemed to have really bad noise associated with the contour plots for ETMY, I think from one of the ALS loops still being active and  trying to lock which flashed some extra light onto the HWS periodically and screwed up the images.

Note: It is a bit difficult to adjust PZT2 to a point where we only saw the ETMY reflection (ETMX still works well), so it seems like the values measured by Nutsinee in aLOG-35979 are no longer valid.  I also found it difficult to search for the new offsets needed so Sheila suggested changing the green QPD offsets instead while the PZT servo was in-loop to make the measurement more repeatable:

- H1:ALS-Y_IP_ANG_YAW_OFFSET = -750 cnts

- H1:ALS-Y_IP_ANG_PIT_OFFSET = 840 cnts

- H1:ALS-X_IP_ANG_YAW_OFFSET = -1000 cnts

We also turned off the PLL locking so that ALS doesn't try to lock as well.

I've attached the first 180 secs after power up, there seems to be some absorption present but no obvious point absorbers.  However, the things to keep in mind are that the ALS-ETM sampling spot size is only about 5 cm in diameter and the overlap with the resonant IR beam is assumed based off the locking process to get up to DC_READOUT and there could be a more precise way to get better overlap between the two beams.

DC_READOUT: 2017-08-29 03:30:00 UTC

NLN: 2017-08-29 03:43:00 UTC

Corner 2 Chassis Modified for Squeezer (SQZ)

Daniel, Marc

WP7129 

We successfully installed an Anybus Modbus adapter to the Corner 2 Chassis in the CER to prepare for the installation of squeezer.

PSL Weekly FAMIS Tasks (FAMIS 3665 & 8437)

This morning I completed the weekly PSL FAMIS tasks.

HPO Diode Current Adjustment (FAMIS 8437)

With the ISS turned OFF, I adjusted the operating current of the HPO pump diode boxes.  DB1 increased by 0.2A and no change on DB2, DB3, and DB4.  The changes are summarized in the below table; I also attached a screenshot of the PSL Beckhoff main screen for future reference.

	Operating Current (A)
	Old	New
DB1	49.8	50.0
DB2	52.7	52.7
DB3	52.7	52.7
DB4	52.7	52.7

I also adjusted the operating temperatures of the DBs; changes summarized in the below table:

	DB1		DB2		DB3		DB4
	Old	New	Old	New	Old	New	Old	New
D1	28.5	28.5	20.0	19.5	21.0	21.0	23.5	23.0
D2	28.5	28.5	19.5	19.0	25.0	25.0	21.0	20.5
D3	28.5	28.5	20.5	20.0	25.0	25.0	22.5	22.0
D4	28.5	28.5	18.5	18.0	22.0	22.0	21.0	20.5
D5	28.5	28.5	18.5	18.0	26.0	26.0	23.0	22.5
D6	28.5	28.5	19.0	18.5	20.5	20.5	23.0	22.5
D7	28.5	28.5	19.5	19.0	21.5	21.5	23.0	22.5

The HPO is now outputting 154.9W and the ISS is back ON.  This completes FAMIS 8437.

PSL Power Watchdog Reset (FAMIS 3665)

I reset both PSL power watchdogs at 16:43 UTC (9:43 PDT).  This completes FAMIS 3665.

TCSX Chiller Trip

Jason O., Thomas V., TJ S.

TCSX chiller tripped at Aug 29 2017 11:21:40 UTC (1188040918 GPS). Flow rate only dropped to ~2.55gpm, this should not trip until 2.0gpm. See attached.

This 2.0gpm limit is set analog via some resistors in the controller. The plan, sometime in the future, is to test this controller and make sure that the resistance is what it is suppose to be, and then fix/replace if necessary.

Thomas and I went out to the LVEA to reset the interlock and it came right back. Verbal briefly complained that it had turned off a few minutes after we got back, but it seems that it just lost lock briefly and the power fell low enough that Verbal caught it. Everything seems okay now.

Swap DARM control to ITMX

Sheila, TVo

We successfully swapped DARM control to ITMX.

In this configuration the TMX_DRIVE_ALIGN_GAIN = 150 compared to ETMY_DRIVEALIGN_GAIN = 30 is roughly the right actuation strengths, the OL DARM TF is attached and is roughly unchanged.

 This swap allows us to do a charge measurement on ETMY which Sheila will post about in a separate aLOG.  This did not change the mystery low frequency noise.

Violin mode frequency changes from in-air measurements to in-vacuum complete results for LHO and LLO

I have compiled the results of in-air measurements during installation and in-vacuum measurements from the alogs; 14231 LLO (including corrections mentioned in alogs 21652 and 27901) and 17610 at LHO (including corrections mentioned on the comments).

In the case when a frequency split is shown on in-vacuum measurements we have taken the average of both frequencies. I have grouped these numbers per front and back fibres, then per test mass and then per detector, finally I obtained the difference as (in-vacuum – in-air) including the sign:

We notice that in most cases the frequency difference is always positive, so frequency increases when moving the suspension to in-vacuum.

The increase in frequency is always a few hundred mHz (mean of 0.3Hz and median of 0.4Hz), with a clear outlier on LLO_ITMY_FL (which as explained here seems to be involved with uncertainty in the identification).

There is not clear difference in frequency variation between front and back fibres (especially no sign difference) which would indicate pitch effect.

However, notice that as per the Technical document T1700399 the expected increase in frequency due to buoyancy is of 0.14Hz, and the variation in frequency due to pitch angles of 2mHz is of 0.33Hz (although that would be an opposite sign change between front and back fibres). Therefore while the observed changes cannot be explained through pitch and buoyancy alone, they are of the same order.