TITLE: 04/01 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 70Mpc
OUTGOING OPERATOR: Travis
CURRENT ENVIRONMENT:
Wind: 19mph Gusts, 16mph 5min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.34 μm/s
QUICK SUMMARY: Smooth sailing at 70Mpc for almost 8hours
TITLE: 04/01 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 70Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY: Observing for ~8 hours. Relocked early in the shift. No issues to report.
LOG: See previous aLogs.
Locked for ~4 hours. No issues.
Begin 1 hour stand down.
No issues relocking.
Shift Summary: Run A2L check script; Pitch is around 0.6, Yaw is below reference. Lost lock, reason unknown. Had trouble with ALS locking, finding IR and DRMI_1F. Ran initial alignment. On relocking, broke lock, twice on FIND_IR ALS_DIFF. Third time made it all the way to NLN. Back to Observing.
Ran A2L check script. Pitch is up to 0.9, Yaw is OK. Will run correction script when opportunity presents.
Damping unruly PI Modes 27 & 28
Lost lock a second time, with no apparent cause. Did not need realignment. During FIND_IR lost lock several times during ALS_DIFF. From the log it looked like the offset was being moved from 1368 to 0 and then back to 1368. The lock was breaking on the second jump of the offset to 1368. Made it through FIND_IR just as Travis was coming on shift. Relocking is proceeding.
TITLE: 04/01 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Jeff
CURRENT ENVIRONMENT:
Wind: 7mph Gusts, 4mph 5min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.26 μm/s
QUICK SUMMARY: Unlocked before my arrival. Relocking seems to be going OK with none of the issues noted by previous operators thus far.
First 3 hours of shift were good observing time. Lost lock - reason unknown. Had trouble with ALS Locking, IR, and DRMI_1F, so ran initial alignment. On relocking, broke a couple of times on FIND_IR for ALS_DIFF. After this relocking went OK. Reset the ETMX RMS WD. Finally relocked at NLN. IFO in Observing, 29.2W, and 75.2 Mpc. Wind and seismic are low.
TITLE: 04/01 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 68Mpc
INCOMING OPERATOR: Jeff
SHIFT SUMMARY: One lockloss that I couldn't figure out. There was a small earthquake coincidentally at the same time, but it didnt look to me like that was the cause, there was not enough motion on the platforms. Relocking had some minor annoyances, see my last alog for more info.
Not a straight forward relock. I couldn't get green to lock without having to move the TMSs so I went to do an initial alignment, but then the fiber polarization was >20% on the Y laser. After adjusting that and moving through IA, MICH would not dark lock. The alignment looked really good but it still would only lock bright. The dark offsets didn't look great so I ran the scripts for that hoping it might help. Then INPUT_ALIGN refused to lock. This is exactly what happened after the harmonic oscillator was replaced recently so I was getting worried, but bumping up the LSC XARM gain eventually worked. I couldnt bring the gain back down or it would kick the IMC and lose lock. After this the rest of IA went well, and locking was no problem.
Bounce is damping slowly but we are back to observing.
After 45hours and 22min it had enough. There was a small earthquake passing through (4.8 from Guatemala) but it didnt seem big enough to knock us out.
TITLE: 03/31 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 68Mpc
OUTGOING OPERATOR: Ed
CURRENT ENVIRONMENT:
Wind: 7mph Gusts, 6mph 5min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.25 μm/s
QUICK SUMMARY: 42hrs long so far. wind is calm, seismic is calm, and range looks good.
b>TITLE: 03/31 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 67Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:
H1 locked the entire shift at fairly good range for over 40hrs. We rode out 1 .4um/s shake. H1 could use a good shot of a2l. ETMY is .9 in YAW and ETMX is not far behind. uSeism is trending up a bit. Handing off to TJ.
LOG:
15:45 Richard to X arm vault and Fil to MX
15:47 Karen into Optics lab
19:18 Tour group in control room
19:57 Second tour group in the control room
20:00 Bubba reported that baers were a couple hundred meters from the corner station on Y arm
20:17 Richard out to the vault
20:49 Jim turning of BRSY temporarily
20:52 Jim done
As Krishna noted in aLog 35160, this machine does not have a lot of extra juice to run this. I should have closed out before but was watching the diagnostics. Jim turned off the sensor correction so in case the session closing glitched things, it would not glith the ISI/IFO. It did not and SC has been turned back on.
Starting CP3 fill. LLCV enabled. LLCV set to manual control. LLCV set to 50% open. Fill completed in 571 seconds. TC B did not register fill. LLCV set back to 17.0% open. Starting CP4 fill. LLCV enabled. LLCV set to manual control. LLCV set to 70% open. Fill completed in 3188 seconds. TC A did not register fill. LLCV set back to 33.0% open.
Raised CP3 to 18% open (was 17%) and CP4 to 36% open (was 33%).
FYI we are losing our striptool scans for these fills. Robo-log will still be generated. Also the text alert will be generated at noon (rather than 10:45) reminding us to check that fill completed.
Added more insulation to the BRSY auxcillary table supporting the T240 seismometer, see 35147, on Tuesday. We saw improvement in the low frequency noise after insulating the supporting legs of the table, see 34869, so more on the table was warranted.
Attached are spectra before and after.
It is a little hard to see but I think the story is good. The upper plot shows the Y axis and the X axis traces are below. The reference traces are from 26 March 1000utc when the wind was very low. The current traces are from 31 March 1120utc, two days after the insulation was added to the table. Generally, comparing suggests the insulation has improved things below 60mHz. Maybe little improvement on Y below 10mHz.
Was logged on checking health from the earlier invasive work. Everything was working fine so I closed (pushed X) on the remote desktop shell. The BRS output went to never never land and the ISI tripped. This of course did nothing useful for the the IFO or Observation mode.
When I logged back onto the BRSY, it was still running but giving some errors and the output was still very rung up. I am not sure which was causing which though. Following the BRS2 Manual (T1600103), restarted the TwinCat code, killed the old occurance and restarted the C#, and finally the EPICS. Exited the session the same way and this time it survived. Yikes!
The amplitude is still a bit large with the camera image swinging into the reference image on the edge. When that stays off the edge during its cycle, the BRS will be useful again.
The BRSY is now damping itself down and is no longer swinging out of range. But it is still getting itself under control. It is coming down quickly but may be some time. Operators should feel free to contact me if they aren't sure if it can be returned to service.
It is strongly advised to not login to the BRS machines when they are being used. This is because the spike in CPU-use disrupts the autocollimator fitting routine. This causes ~seconds long delays in the tilt output which affects the tilt-subtraction and so on.
See red and blue VS green. Bumps are at around [4, 5, 6, 7, 8]*12.125 Hz or so.
When it was really bad (red), it was easily identifiable in detchar summary page, not so when it was mildly bad (blue).
I ran coherence tool on these lines. I first tried to find a comb over there but failed. Then I tried to find them as single lines. I looked for 6 single lines: 12.125Hz, 48.5Hz, 60.625Hz, 72.75Hz, 84.875Hz, 97Hz. Two of them are not found in the coherence tool. Here are the results:
12.5Hz: https://ldas-jobs.ligo-wa.caltech.edu/~duo.tao/O2_line_12.125/index.html (Weak results and the structure does not look like a single line)
48.5Hz: https://ldas-jobs.ligo-wa.caltech.edu/~duo.tao/O2_line_48.5/index.html (Found in four of the weeks, in some EX and EY magnetometers. There are some channels that do not look like a single line. But there seems to be something going on so I showed them.)
60.625Hz: https://ldas-jobs.ligo-wa.caltech.edu/~duo.tao/O2_line_60.625/index.html (Not found)
72.75Hz: https://ldas-jobs.ligo-wa.caltech.edu/~duo.tao/O2_line_72.75/index.html (Not found)
84.875Hz: https://ldas-jobs.ligo-wa.caltech.edu/~duo.tao/O2_line_84.875/index.html (Weak. Only found in one channel and the structure does not look a single line)
97Hz: https://ldas-jobs.ligo-wa.caltech.edu/~duo.tao/O2_line_97/index.html (Found in many EX and EY magnetometers)
Robert's measurements seem to suggest that this is the resonance of one of the baffles.
https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=35166
I've attached about 10 hours of BRS-Y driftmon data around the time of this crash. It looks like this crash was caused by trying to use BRS-Y in a bad range. Even if the data looks temporarily smooth, BRS-Y should not be used if driftmon is below -15k counts.
The close time association with closing of the remote desktop terminal was likely just a coincidence. It is still advised to not login to the machine remotely when BRS-Y is being used for feedforward, unless really necessary.