C. Cahillane

Posted are the results for the total frequency dependent calibration uncertainty budget for LHO.  
These results are for before the updated actuation models at LHO.  I still need to get the updated PUM and TST drivers, but this should be close enough for now.

The method used to construct this result is as follows:
1) MCMC fit calibration model parameters to the reference models from Nov 12, 2016.  
2) Record samples from the MCMC.
3) Get residuals = (Meas/MCMC Fit) for ALL measurements, not just reference model, and find systematic errors via a Gaussian Process (GP).
4) GP outputs a mean posterior function (systematic error) and a covariance matrix (uncertainty) relating all training data.
5) Record both the GP systematic error and covariance matrix.
6) Now, assemble the response function results from the MCMC and GP by taking a random sample from the MCMC results and generating a potential systematic error from our GP mean systematic error + covariance matrix.  

The final results are showed in Plot 1.  All 1000 instances are plotted in white, while the mean and 68% confidence intervals about the mean are plotted in red.  

J. Kissel

I've noticed the amplitude spectral density of PCALY RX PD looks to be showing the same sort of clipping behavior that was present early last October (Identified in LHO aLOG 30827; Solved in LHO aLOG 30877). I'll send a note to team PCAL and suggest they take a look tomorrow during maintenance.

The attached plot shows the ASD of PCALY RX PD (in PURPLE) and CAL-DELTAL_EXTERNAL (in RED) during the most recent lock stretch (2017-01-09 19:30:49 UTC) compared against PCALY RX PD right after they'd fixed the clipping issue last time (2016-10-26 17:26:40 UTC).

Unclear why the clipping has returned, other than to say that what is a "good" alignment of ETMY that the exit PCAL beams were aligned to may have changed / drifted over time. A 20 day trend shows that clipping only started after the IFO returned to operation on Jan 4th.

This morning we sat in nominal low noise without going to observing from 19:21 to 19:51 UTC (Jan 9th) in a configuration that should be much better for the 1084Hz glitches. (WP6420)  

On Friday we noticed that the 1084Hz feature is due to OMC length fluctuations, and that the glitch problem started on Oct 11th when the dither line amplitude was decreased (alog 30380 ).  This morning I noticed that the digital gain change described in alog 30380 that was intended to compensate for the reduced dither amplitude didn't make it into any guardian, so that we have had a UGF that was a factor of 8 lower than what I used when projecting OMC length noise to DARM: 30510 The first attachment shows open loop gain measurements from the 3 configurations: before oct 11th (high dither amplitude), after october 11th (lower dither amplitude, uncompensated) and the test configuration (lower dither amplitude, compensated).  

We ran with the servo gain set to 24 (to give us the nominal 6Hz ugf) and the lowered dither line amplitude from 19:21 UTC to 19:51 UTC Jan 9th.  You can see the spectrum durring this stretch in the second attached screenshot, in the test configuration the peak around 1083Hz is gone, with just the pcal line visible, and the OMC length dither at 4100Hz is reduced by more than an order of magnitude. You can also compare the glitches from this lock stretch with one from yesterday  to see that the glitches at 1084 Hz seem to be gone. This is probably the configuration we would like to run with for now, but we may try one more test with increased dither line amplitude.  

Other notes because we don't have an operator  today due to weather:

This morning all 4 test mass ISIs were tripped probably from the Earthquake last night that brought the EQ  BLRMS to 10 um/second around midnight UTC.  ITMY tripped again while it was re-isolating, no problem on the second try. 

Richard topped added 400mL to the TCSY chiller around 10:15 or 10:30 local time, since we were getting low flow alarms. The flow alarms came back a few minutes before 11am local time.  

I went through inital alingment witout problems and got to DC_readout transition. Then I measured the UGF of the OMC length loop in preparation for increasing the dither line height   From that measurement and trends it became clear that when the OMC dither amplitude was reduced, the compensation of the OMC digital gain described in didn't make it into the guardian.  This means we have been operating with a UGF in the OMC length loop that was a factor of 8 too low since mid october.  

We arrived in low noise at 19:21 UTC with the OMC ugf increased to 6Hz.  After about a half hour PI modes 27 and 28 rang up, and I wasn't fast enough to get them under control so we lost lock.  

Starting CP3 fill. LLCV enabled. LLCV set to manual control. LLCV set to 50% open. Fill completed in 27 seconds. LLCV set back to 14.0% open.
Starting CP4 fill. LLCV enabled. LLCV set to manual control. LLCV set to 70% open. Fill completed in 94 seconds. TC B did not register fill. LLCV set back to 35.0% open.

Replaced IP5 controller in mech. room with GAMMA LPC (+) controller (WP 6421). One of two channels of the old controller was faulting "over temperature," a typical error/failure mode on the Varian controllers. LVEA pressures rose slightly due to reduced pumping speed (see aLOG 33070) over weekend. We will update CDS signal cabling (right now pump appears to be in error, but it is actually fully functioning) and reboot Beckhoff at next opportune maintenance period.

Due to road condition in town, many cannot make it to the site today. Site, route 10 and 240 are already reasonable.

Sheila is in the control room trying to lock IFO.

I'm watching.

The h1tw1 /trend file system is in need of repair, so recent trend data will not be available for a bit.   

The roads out to the site are packed snow with ice in places, nice thing is Hanford cancelled work so not too many people on the roads coming out here. 

Chris S. and I have been out here since 5 A.M. plowing roads, parking lots, and sidewalks. The site driveway has been plowed as has the OSB parking lot and walkways to the OSB. We are working on the LSB parking lot. We have not had a chance to spread ice melt yet. Sidewalks are still a little slippery.

Drive safely. 

Head flows since the last laser trip.  Previously head 3 was the noisy one.  Since the restart the
noisy channel is now head 2.  The minimum observed flows were still above the trip point though.

Whilst checking out how the PSL behaved after Saturday's trip, I noticed the following behaviour in
the diode and chiller room environment monitors.  It seems a little odd to me that things cycle on
order of every ~25 minutes.  The chiller room somewhat more so than the diode room.

I second Travis' decision to stay home. Note that road conditions tomorrow may be BAD so please check conditions and take your time on the road. 

https://www.wunderground.com/US/WA/028.html?MR=1

http://www.hanford.gov/c.cfm/advisory/

	... Winter Weather Advisory remains in effect until 7 am PST
Monday... 

* locations... Connell... Prosser... Tri-Cities.

* Ice accumulations... less than a tenth of an inch.

* Snow accumulations... 1 to 2 inches of snow and sleet.

* Timing... wintry will continue through 4 PM. Another round of
  precip is expected during the early morning hours of Monday.

* Impacts... snow and ice will make roadways hazardous.

* Winds... north 5 to 10 mph.

* Temperatures... in the lower 20s... rising into the upper 20s 
  and lower 30s Sunday evening.

* Snow level... basin floor rising to 1000 feet Sunday evening.

* Web page: for a detailed view of the hazard area visit 
  http://www.Wrh.NOAA.Gov/map/?Wfo=pdt.

Precautionary/preparedness actions... 

A Winter Weather Advisory means that periods of snow... sleet... or
freezing rain will cause travel difficulties. Be prepared for
slippery roads and limited visibilities... and use caution while
driving.

I have contacted Corey and Keita, and with their blessing, I have decided to forego coming in for my Eve shift.  With several inches of snow already today, and the forecast for it to change to freezing rain later tonight, I'm going to play the safety card.

• Initial Alignment
• adjusted ALS fiber polarization
• relocked
• in NLN
• in Observe @ 23:04:57
• JeffK heading home
• Rick was here, assuming he's gone home
• I'm heading out asap

Ran the diaggui template for the HAM and BSC ISI CPSs (CPS'...).

No overall issue with one sensor being elevated.

I found one thing that is maybe a known and understood feature, but I didn't find it in the alog with my searching (maybe the wrong search words?).

I notice that there is noise in HAM2, HAM3, HAM4, and HAM6 around 41.3Hz, and the elevated noise level goes from 41Hz to about 41.6Hz.

This noise is not present in the 1 Dec 2016 plots, there seems to be hint of it in the 14 Dec 2016 plots, and it's clearly visible in the 1 Jan 2017 plots.

Attached:

• BSC
• HAM
• HAM, zoomed in to 40-70Hz

(Chandra, Gerardo)

Remote logged in to find out status of IP5.  We lost one channel on IP5 at around 13:02 utc, the other channel still up.

~1625 - 1630 hrs. local -> Kyle in and out of LVEA

Shut down rotating shaft vacuum pumps which had been pumping PT180 (BSC8) for the past 8 days.  Also, removed ladder which had been leaning against BSC8.  We should now have enough data to compare and contrast PT180's behavior between when it is exposed/pumped by the YBM to that of when exposed/pumped by a locally mounted turbo.  

Recall that the post-detect era installed Bayard-Alpert gauges PT170, PT180 and PT140 all exhibit a slow upward drift that the iLIGO era Cold Cathode gauges (sampling same vacuum volume) do not.  Understanding/believing our gauges is critical.  

We will decouple the vacuum pumps from PT180 on the next maintenance day.