Displaying reports 55961-55980 of 88164.Go to page Start 2795 2796 2797 2798 2799 2800 2801 2802 2803 End
Reports until 08:24, Tuesday 10 January 2017
H1 General
jim.warner@LIGO.ORG - posted 08:24, Tuesday 10 January 2017 (33123)
Shift Summary

TITLE: 01/10 Owl Shift: 08:00-16:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: EQ, maintenance day
INCOMING OPERATOR: Nutsinee?
CURRENT ENVIRONMENT:
    Wind: 11mph Gusts, 10mph 5min avg
    Primary useism: 0.24 μm/s
    Secondary useism: 0.41 μm/s
QUICK SUMMARY:

I had problems with PI modes 27 & 28 all night, they needed constant attention. 27 broke lock once, and when I got back up, looking at spectra showed that the modes that were ringing up were outside the mode 27 bandpass filter, so I switched from FM5 (18036.5 hz) to FM4(18040 hz), and could at least control the PI for the rest of the night, but it needed frequent tweaks to the PLL phase.

Maintenance has started, Peter headed out to the PSL after an EQ knocked us out, Krishna has started a software upgrade to the BRSs.
 

LHO General
corey.gray@LIGO.ORG - posted 00:20, Tuesday 10 January 2017 (33115)
EVE Operator Summary

TITLE: 01/10 Eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC

STATE of H1: Observing at 61.4621Mpc
INCOMING OPERATOR: Jim
SHIFT SUMMARY:
LOG:
H1 SEI (SEI)
corey.gray@LIGO.ORG - posted 23:18, Monday 09 January 2017 - last comment - 23:32, Monday 09 January 2017(33120)
Earthquake Report: 7.9, Philippines, H1 (&L1) Lockloss
Comments related to this report
corey.gray@LIGO.ORG - 23:32, Monday 09 January 2017 (33121)

Took ISI CONFIG to BIG_EARTHQUAKE_NOBRSXY after the lockloss & stayed there for about 30min (6:40-7:12utc) per text from Warner.  

Now just holding at LOCKING_ARMS_GREEN until noticeable seismic motion (seen via ALSx/y & Tidal traces) decays, also per text from Warner (who is inbound shortly).

Seismic band (0.03-0.1Hz) has dropped down to 0.5um/s now.

H1 AOS (DetChar)
jess.mciver@LIGO.ORG - posted 22:51, Monday 09 January 2017 (33119)
DQ shift report for Jan 04-08

LHO DQ summary:

Fire alarm follow-up:

For more details, please see the DQ shift pages: 2017Jan02, 2017Jan05

LHO General
corey.gray@LIGO.ORG - posted 20:37, Monday 09 January 2017 (33117)
Mid Shift Status

H1 has been in OBSERVING for over 6.5hrs.  Range is a hovering around 60Mpc.

Minimal activity.  Gerardo just arrived to make a cable for an IP5 in Mechanical Room.

Just had a TCSy Chiller Flow Alarm.

H1 DetChar (DetChar)
corey.gray@LIGO.ORG - posted 17:35, Monday 09 January 2017 - last comment - 07:35, Tuesday 10 January 2017(33116)
Flagging This Observing Mode Segment Due to Snow Plowing Around LVEA

On Kissel's suggestion, flagging H1 data from 23:45-1:25UTC, due to snow plowing (by Bubba).  This is for CP2 access for LN2 delivery Tues morning.  Activity could be seen in our 3-10 & 10-30Hz bands.  This brought H1 range down below 50Mpc at times during this period.  Drifts were several feet high & it took him almost 2hrs just to plow just this short section.

Comments related to this report
laura.nuttall@LIGO.ORG - 07:35, Tuesday 10 January 2017 (33122)

H1:DCH-SNOW_PLOW:1 added!

LHO General
corey.gray@LIGO.ORG - posted 16:48, Monday 09 January 2017 (33113)
Eve Operator Transition

TITLE: 01/10 Eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC

STATE of H1: Observing at 48Mpc
OUTGOING OPERATOR: No EVE, OWL, DAY operators over the last 24hrs due to heavy snow.
CURRENT ENVIRONMENT:
    Wind: 7mph Gusts, 5mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.30 μm/s 
Light snow as I drove onto site (roads were plowed on most of the highways [SR240 & RT10]).  On site, snow is plowed for the access road to the LSB/OSB and as well as their parking lots.  Snow not plowed down the X & Y arms.  
 
QUICK SUMMARY:
H1 CAL (CAL)
craig.cahillane@LIGO.ORG - posted 15:55, Monday 09 January 2017 (33111)
LHO O2 Frequency-Dependent Calibration Uncertainty
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.  
Images attached to this report
H1 CAL (CAL, DetChar)
jeffrey.kissel@LIGO.ORG - posted 13:26, Monday 09 January 2017 - last comment - 16:04, Monday 09 January 2017(33108)
PCALY RX PD Clipping Again?
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.
Images attached to this report
Comments related to this report
sudarshan.karki@LIGO.ORG - 16:04, Monday 09 January 2017 (33112)

I made a comparison between TxPD and RxPD at calibartion line frequencies beginning Dec 1 until yesterday. TxPD has not changed over time but RxPD changed after the break.

Images attached to this comment
Non-image files attached to this comment
H1 ISC (DetChar, TCS)
sheila.dwyer@LIGO.ORG - posted 12:29, Monday 09 January 2017 - last comment - 07:21, Friday 13 January 2017(33104)
change in OMC length gain helps with 1083 Hz glitches

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 DARM30510 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.  

Images attached to this report
Comments related to this report
andrew.lundgren@LIGO.ORG - 16:34, Monday 09 January 2017 (33114)DetChar, ISC
Here's a graphical version of what Sheila wrote, showing the time on Oct 11 when the 1083 Hz glitches started. The dither amplitude was reduced at 3:20 UTC, but the servo gain was increased to compensate. There are no 1083 Hz glitches at this time. Severe RF45 noise starts an hour later and lasts until the end of the lock. The 1083 Hz glitches are evident from the beginning of the next lock, and persist in every lock until the recent fix.

The dither amplitude stayed low in the second lock, but the servo gain was reset back to its low value. Apparently, both need to be low to produce the glitches.
Non-image files attached to this comment
sheila.dwyer@LIGO.ORG - 11:17, Thursday 12 January 2017 (33175)

Keita tells me that people are concerned about making this change because of the increased noise below 25 Hz in the screenshot attached to the original post.  We did not run the A2L decoupling durring this lock strech, and it was not well tuned.  The shape of the HARD loop cut off at 25Hz is visible in the spectrum, which is one way of identifying bad ASC noise.  The high coherence between CHARD P and DARM at this time is another way of seeing that this is angular noise (attachment). 

So I think that this is unrelated to the OMC gain change and not really a problem. 

Images attached to this comment
joshua.smith@LIGO.ORG - 11:40, Thursday 12 January 2017 (33176)DetChar, ISC

1080Hz removal OMC gain/line conditions, does it make more low frequency noise?
Josh, Andy, TJ, Beverly

Conclusion: For two on/off times each for the two OMC gain tests (total 8 times) it looks like the high gain / low line configuration that takes away 1080 Hz (and also takes away some bumps around 6280Hz) coincides with a bit more noise below 25Hz.

Request: We hope this connection with noise below 25Hz is chance (It might have just been drift and we chose times unluckily) and we would like debunk/confirm it. We could do that with a couple cycles of on/off, (e.g. 5 minutes each, with the current configuration vs high gain / low dither configuration). 

See the attached PDF. The pages are: 

  • 2,3: January 9th test configuration from Sheila's page: "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." Red/Orange are the test time with low line / high gain, and no 1080Hz
  • 4,5: Similar experiment from October. Blue/green are the test time with low line / high gain, and no 1080Hz.

Also: There is no coherence above 10Hz between STRAIN and OMC LSC SERVO/I for any of these test times. So coupling must be non-linear. 
Also: When the 1080Hz bumps disappear we also see a bump around 6280Hz disappear (attached image, sorry no x-axis label but its 6280Hz)

Images attached to this comment
Non-image files attached to this comment
andrew.lundgren@LIGO.ORG - 12:10, Thursday 12 January 2017 (33177)DetChar, ISC
Our post crossed with Sheila's. If possible, we'd still like to see a quick on/off test with the A2L tuned. Could we have five minutes with the gain high and then ramp it down? Maybe with one repeat. Since this is a non-linear effect, we'd like to make sure there's no funny coupling with the CHARD noise. We're not too worried by excess noise below 25 Hz now, but it might be important when we're able to push lower.
sheila.dwyer@LIGO.ORG - 16:34, Thursday 12 January 2017 (33183)

While LLO was down I attempted to do a test by increasing the OMC length gain while in lock, which unlocked the IFO.  So on/off tests aren't possible.  Edit:  I broke the lock by changing the gain after the integrator (which had been OK when not on DC readout), we can change the gain upstream instead without unlocking.  

For now I put the new gain into the guardian so the next lock will be with the increased gain, and hopefully see that the low frequency noise is fine. 

Now we have relocked, Patrick ran a2l, and Jeff, Evan, Krishna and I did an on off test by ramping H1:OMC-LSC_I_GAIN:

  • high gain for about 15 minutes before 23:55 UTC Jan 12th
  • low gain from 25:56:20 Jan 12th to 0:03:21 UTC Jan 13th
  • high gain from 0:04 UTC to 0:13:22 UTC
  • back to low gain

The attached screen shot using the same color scheme as in the presentation above shows that there is not a difference at low frequency between high gain and low gain.  

We are back in observing in the low gain configuration, but the gain is set in an unusual way (and accepted in SDF so that we can go to obsevering). Keita would like us to hear confirmation from detchar before making this permanent. 

Images attached to this comment
joshua.smith@LIGO.ORG - 07:21, Friday 13 January 2017 (33214)DetChar, ISC

Thank you Sheila, this looks really good. No change at low frequency. 1080Hz gone. The 6280Hz just varies on its own timescale. From our end we're happy with the configuration change since it only does good. Sorry for the red herring about low frequencies. 

Images attached to this comment
LHO VE
logbook/robot/script0.cds.ligo-wa.caltech.edu@LIGO.ORG - posted 12:10, Monday 09 January 2017 (33106)
CP3, CP4 Autofill 2017_01_09
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.
Images attached to this report
LHO VE
chandra.romel@LIGO.ORG - posted 12:05, Monday 09 January 2017 - last comment - 22:33, Monday 09 January 2017(33105)
IP5 controller replaced

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.

Comments related to this report
gerardo.moreno@LIGO.ORG - 22:33, Monday 09 January 2017 (33118)VE

Installed new cable for IP5, after removing old cables/connectors for previous version of controller.

Note: New controller is using the connection to pump A of old system, same calibration as other similar GAMMA (LPC +) controllers.

H1 General
keita.kawabe@LIGO.ORG - posted 10:51, Monday 09 January 2017 (33103)
Mid-morniong report

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.

LHO VE (VE)
gerardo.moreno@LIGO.ORG - posted 10:30, Saturday 07 January 2017 - last comment - 13:58, Monday 09 January 2017(33070)
IP5 Channel A Dead

(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.

Images attached to this report
Comments related to this report
gerardo.moreno@LIGO.ORG - 10:35, Saturday 07 January 2017 (33071)VE

Attached is the pressure change due to loss of channel A.  Included are some channels from both Mid stations.

Images attached to this comment
chandra.romel@LIGO.ORG - 10:39, Saturday 07 January 2017 (33072)

We'll replace power supply Monday.

chandra.romel@LIGO.ORG - 13:58, Monday 09 January 2017 (33110)

One channel out on IP5 at corner has an affect on pressure 2.5 miles away (EY only).

Images attached to this comment
LHO VE
kyle.ryan@LIGO.ORG - posted 16:51, Wednesday 04 January 2017 - last comment - 13:39, Monday 09 January 2017(32972)
~1625 hrs. local -> Isolated PT180 from rotating shaft vacuum pumps and exposed PT180 to YBM
~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.   
Comments related to this report
chandra.romel@LIGO.ORG - 14:43, Thursday 05 January 2017 (32993)

Pressure reading from PT180 is once again rising after being valved into main volume. We suspect the water load is causing this. End stations show no sign but also get 2.5x more pumping speed from cyropumps due to smaller volume.

PT140 pressure reading on diagonal volume (no crypopump) started dropping this week after a three month incline. These changes are due to LVEA temperature fluctuations.

Images attached to this comment
chandra.romel@LIGO.ORG - 13:39, Monday 09 January 2017 (33109)

Correction:  water pumping speed is more like 1.8x more at end stations. 

Corner volume = 445,000 liters

End volume = 88,000 liters

Corner cyropumping = [100,000 - 3,000] x 2 (L/s)

End cryopuming = 100,000 - 30,000 (L/s)

Displaying reports 55961-55980 of 88164.Go to page Start 2795 2796 2797 2798 2799 2800 2801 2802 2803 End