Displaying reports 59001-59020 of 83069.Go to page Start 2947 2948 2949 2950 2951 2952 2953 2954 2955 End
Reports until 14:15, Tuesday 05 January 2016
H1 SEI
hugh.radkins@LIGO.ORG - posted 14:15, Tuesday 05 January 2016 (24711)
LHO Monthly HEPI Pump Output Trends

No new news here--Everyone chugging along.  Attached is 40 days of the first pressure sensor on the Pump Station manifold and the control output to the motor.

Remarks:  All four CS pumps have a perfect flatlined output (showing only one,) no this is not news.  EX's excess noise continues in evidence, notice the ~15 days of quieter readings.  At EndY, the daily and weekly glitches continue as before.

No indications of pump output loss.

Images attached to this report
H1 SEI
hugh.radkins@LIGO.ORG - posted 13:37, Tuesday 05 January 2016 (24710)
LHO STS2s Mass Positions Centered-Finally

Attached is a plot of the STS2's Mass Positions.  Finally got them all centered (something below 5000cts)

Found that ETMY did not have the Binary I/O cable from the Bin Output to the STS2 Interface so this was not going to re-center remotely anyway.  Vincent pulled that cable but we don't quite understand.  I can tell you though that the recentering does not work via the medm/cable but the signal select and period select toggling does work...  We've left that cable unplugged and did the centering at ETMY via the front panel button.

Images attached to this report
H1 AOS
craig.cahillane@LIGO.ORG - posted 13:21, Tuesday 05 January 2016 (24709)
LHO O1 Uncertainty Budget at GPSTime = 1135136350
C. Cahillane

I have constructed the uncertainty budget of LHO at GPSTime = 1135136350.

The kappa values are given at 11546.

Just a reminder on the differences between the calibration versions (according to me and my results):

C00 = Sensing, Actuation, and Digital filters given by DARMmodel (I used the DARMparams from GPSTime = 1127083151)
C01 = No kappa corrections, but static frequency dependence corrected.
C02 = Kappa_tst and kappa_C corrected, as well as static frequency dependence corrected. Kappa_pu and cavity pole f_c NOT corrected.
C03 = "Perfect" calibration, i.e. all kappas and static frequency dependence corrected. 

All comparisons between calibration versions have the C03 "Perfect" calibration in the denominator.  C03 represents the best possible knowledge of the detector according to the calibration group.  All others have some known systematic errors. 

For C01, strain magnitude uncertainty is below 7% and strain phase uncertainty is below 3.5 degrees. (See PDF 1 Plot 2)
For C01, maximum strain magnitude error over C03 is 0.95 and maximum strain phase error over C03 is below 3 degrees. (See PDF 1 Plot 1)
Non-image files attached to this report
H1 General (PSL)
edmond.merilh@LIGO.ORG - posted 10:32, Tuesday 05 January 2016 (24707)
PSL Past 20 day Trends

Here are the trends of the PSL data froim the past 20 days. In reponse to Jeff K's request for more commentary on this data I have conversed with the expert(s) and Jason agreed to provide more analysis.

Images attached to this report
H1 AOS (SUS)
jason.oberling@LIGO.ORG - posted 09:50, Tuesday 05 January 2016 (24706)
ITMy & SR3 OpLevs Re-Centered (WP 5676)

After reviewing the trends I posted yesterday I determined that the ITMy and SR3 oplevs needed re-centering.  This is now complete.  The old and new pitch/yaw values for these oplevs are below.

Old and New Pitch & Yaw Values for ITMy & SR3 Optical Levers
  Old (µrad) New (µrad)
Pitch Yaw Pitch Yaw
ITMy -11.1 -12.1 -0.2 0.0
SR3 -13.8 +5.2 -0.2 -0.1

 

This completes LHO WP #5676.

H1 PSL
jason.oberling@LIGO.ORG - posted 09:41, Tuesday 05 January 2016 (24705)
H1 PSL FE Watchdog Reset

I reset the PSL 35W FE watchdog at 17:33 UTC (9:33 PST).

H1 General
jim.warner@LIGO.ORG - posted 08:02, Tuesday 05 January 2016 (24703)
Shift Summary

Ops Owl Summary: 08-16UTC

State of H1: down for maintenance

Shift Summary:

10:20 Lockloss due to earthquake in the pacific.

12:30 Back up to observing

14:30 Lockloss from POP decay. Range was ratty, maybe due to bad alignment.

15:00 Start initial alignment. I had to touch TMSY to get the Y-arm back.

15:30 Richard to EX to work on webcam

15:45 JeffB to LVEA

H1 CAL
jeffrey.kissel@LIGO.ORG - posted 07:55, Tuesday 05 January 2016 (24702)
Calibration Week Starts Now!
J. Kissel, J. Warner

Since the IFO is in such poor shape anyways with POP / alignment woes, I've suggested we just begin with calibration measurements needed for today. Jim has brought the acuiring IFO to DOWN, I'm heading down to the Y-End to begin measuring ETMY coil drivers, and the PCAL team should be in shortly and will go to the X-End to begin their standard calibration of the EX RX and TX PDs. Wish us luck! 
H1 General
jim.warner@LIGO.ORG - posted 04:41, Tuesday 05 January 2016 (24701)
Mid shift summary

Just got back to Observe after an earthquake in the Pacific knocked us down. Slightly more difficult than normal, as I lost lock a couple times at fairly high states (Engage ASC Part 3 and Coil Drivers). I noticed that every time I got to Engage ASC Part 3, the Y arm ALS power would start to drop. It would continue to roll off as I waited for ASC loops to converge. Might be an issue there.

H1 SUS (OpsInfo, SUS)
cheryl.vorvick@LIGO.ORG - posted 00:39, Tuesday 05 January 2016 (24699)
PR2 M3 OSEMs have some odd behavior - maybe sick enough to be causing problems

LR behavior has changed over 150 days - trend attached.

Power spectrum of PR2 and SR2 to compare attached also.

Images attached to this report
H1 IOO (IOO, SUS)
cheryl.vorvick@LIGO.ORG - posted 00:36, Tuesday 05 January 2016 (24696)
alignment changes in yaw, for IM1, IM2, IM3, PRM and PR2, over 150 days (all of O1 plus a few days)

I looked into the recent change in H1 behavior, with H1:LSC-POP_A_LF_OUT dropping, and causing lock loss, and see alignment changes that could be contributing to this issue.

The shifting IMs in HAM2 cannot account for alignment changes in the 150 day trend, so there is something else at work here.

Changes in yaw over 150 days:

Changes in pitch, comparing PRM to PR2 (different chambers)

The change in PR2 yaw of +51urad is significantly larger than the changes in the PRM pitch and yaw, and PR2 pitch.

The changes in PR2 yaw may be a response to the cumulative effects of the smaller changes seen in IM1, IM2, and IM3.

Changes in IM pitch:

The change is IM3 yaw of -26urad is significant;y larger than the changes in pitch or yaw in IM1, IM2, and IM3.

Images attached to this report
H1 IOO (IOO, Lockloss, OpsInfo, SUS)
cheryl.vorvick@LIGO.ORG - posted 00:36, Tuesday 05 January 2016 (24697)
alignment of IM2 and PR2 and a failed attempt to save the lock, but left breadcrums to stabilize POP_A_LF

H1 out of Observe at 01:16:37UTC:

Lockloss at 01:35:56UTC:

Summary:

Images attached to this report
H1 General
cheryl.vorvick@LIGO.ORG - posted 00:31, Tuesday 05 January 2016 (24698)
OPS Eve Summary:

Ops Eve Summary: 00-08UTC

State of H1: locked in Observe, range is 74Mpc

Fellow: Keita

Shift Summary:

H1 ISC (DetChar)
keith.riles@LIGO.ORG - posted 21:30, Monday 04 January 2016 - last comment - 16:55, Thursday 18 August 2016(24695)
Narrow lines in (nearly) full O1 data set
Executive summary: 

In regard to narrow lines, the (nearly) full O1 H1 data set is little changed from what was reported for the first week's data: a pervasive 16-Hz comb persists throughout the CW search band (below 2000 Hz), accompanied by a much weaker and more sporadic 8-Hz comb; there remain several distinct 1-Hz and nearly-1-Hz combs below 140 Hz, along with other sporadic combs. The 1459.5 hours of 30-minute FScan SFTs used here span from September 18 to the morning of January 3. The improved statistics make weaker and finer structures more visible than in the 1st week's data. As a result, many new singlet lines have been tagged, and it has become apparent that some previously marked singlets actually belong to newly spotted comb structures. The improved statistics also make it more apparent that the originally spotted combs span a broader bandwidth than marked before Details: Using 1459.5 hours of FScan-generated, Hann-windowed, 30-minute SFTs, I have gone through the first 2000 Hz of the DARM displacement spectrum (CW search band) to identify lines that could contaminate CW searches. This study is very similar to prior studies of ER7 data, ER8 data and the first week of O1 data, but for completeness, I will repeat below some earlier findings. Some sample displacement amplitude spectra are attached directly below, but more extensive sets of spectra are attached in a zipped file. As usual, the spectra look worse than they really are because single-bin lines (0.5 mHz wide) appear disproportionately wide in the graphics A flat-file line list is attached with the same alphabetic coding as in the figures. Findings:

  • A 16-Hz comb pervades the entire 0-2000 Hz band (and well beyond, based on daily FScans)
  • A typically much weaker and sporadic 8-Hz comb (odd harmonics) is also pervasive (all harmonics are labeled in figures, even when not visible)
  • A 1-Hz comb with a 0.5-Hz offset is visible from 10.5 Hz to 133.5 Hz (previously was visible from 15.5 to 78.5 Hz)
  • A 1-Hz comb with zero offset is visible from 16.0 Hz to 102.0 Hz (previously was visible from 20.0 to 68.0 Hz)
  • A 99.9989-Hz comb is visible to its 11th harmonic (was previously visible to its 8th harmonic)
  • The 60-Hz power mains comb is visible to its 9th harmonic (was previously visible to its 6th harmonic)
  • There is a sporadic comb-on-comb with 0.088425-Hz fine spacing that appears with limited spans in three places near harmonics of 77, 154 and 231 Hz (ambiguity in precise fundamental frequency)
  • There is a doublet 31.4127 and 31.4149 Hz comb visible to their 2nd harmonics (previously marked as only a 31.4149-Hz comb)
  • There are three near-1-Hz combs not previous appreciated:
    • 0.99999-Hz comb from 19.2500 to 50.2497 Hz
    • 0.99816-Hz comb from 30.9430 to 60.8878 Hz
    • 0.9992-Hz comb from 30.9738 to 48.9594 Hz
  • There is a doublet comb with spacings of 2.07412 and 2.07423 Hz, visible from their 9th to 32th harmonics (18.7-66.4 Hz)
  • There is a hint of another doublet comb with spacings of 99.9735 and 99.9784 Hz, but they are marked as singlets for now
Line label codes in figures: b - Bounce mode (quad suspension) r - Roll mode (quad suspension) Q - Quad violin mode and harmonics B - Beam splitter violin mode and harmonics C - Calibration lines M - Power mains (60 HZ) s - 16-Hz comb e - 8-Hz comb (odd harmonics) O - 1-Hz comb (0.5-Hz offset) o - weaker 1-Hz and near-1-Hz combs (various offsets, including zero) H - 99.9989-Hz comb J - 31.4127 and 31.4149-Hz combs K - 0.088425-Hz comb t - 2.07412 and 2.07423 combs x - single line (not all singlets in the vicinity of quad violin modes are marked, given the upconversion) Figure 1 - 0-2000 Hz Figure 2 - 20-50 Hz sub-band (shows complexity of combs below ~70 Hz) Figure 3 - 50-100 Hz sub-band (shows continuation of strongest 1-Hz comb with offset of 0.5 Hz) Figure 4 - 1300-1400 Hz sub-band (shows how clean the noise floor is away from 8-Hz, 16-Hz lines at high frequencies Attachments: * Zip file with miscellaneous sub-band spectra (with line labels) * Flat-file list of lines marked on figures
Images attached to this report
Non-image files attached to this report
Comments related to this report
soren.schlassa@LIGO.ORG - 21:25, Tuesday 26 January 2016 (25192)
In week 1 Keith identified a comb-on-comb (labeled K, see attached plot), fine spacing 0.08842 Hz, which shows up sporadically at around 77, 154, and 231 Hz. We found it in a large group of channels, centered at the INPUTOPTICS/SUS-BS/SUS-ITM (see full attached list). It remains clearly visible (especially at 77 Hz) in those channels until week 5 of O1, during which it disappears from all of them in all three regions (see attached example). Therefore, it seems likely that its presence in the full O1 data is an artifact from the first four weeks.
Images attached to this comment
Non-image files attached to this comment
ansel.neunzert@LIGO.ORG - 16:55, Thursday 18 August 2016 (29182)

I recently re-analyzed this data while testing a comb-finding algorithm, and in the process found a new comb which accounts for several peaks marked as singlets in Keith's original post. This comb has a 2.040388 Hz spacing, with visible harmonics from 9th (18.3635 Hz) to 38th (77.5347 Hz). The code I used, and its docs, can be found on gitlab (requires login).

H1 General
jeffrey.bartlett@LIGO.ORG - posted 16:09, Monday 04 January 2016 (24692)
Ops Day Shift Summary
Activity Log: All Times in UTC (PT)

16:00 (08:00) Take over from Jim
16:59 (08:59) Christina & Karen – Going into the mechanical building to deliver supplies
17:25 (09:25) High temp alarm on CS Zone 1B. Will monitor.
17:55 (09:55) Out of Observing to try to improve power recycling gain
18:52 (10:52) Back into Observing mode
19:32 (11:32) Platt Electrical on site with a delivery for Richard
20:50 (12:50) LockLoss – POP_A_LF has been drifting down all morning despite the tweaking of PR2
21:00 (13:00) Start initial alignment and then on to relocking
22:00 (14:00) Travis – Going into the optics lab
22:02 (14:02) GRB Alert – LHO relocking so ignored alert
22:08 (14:08) IFO locked and back into Observing
22:22 (14:22) Travis – Out of the optics lab
22:44 (14:45) Travis – Going into optics lab
22:58 (14:58) Travis – Out of the optics lab
23:10 (15:10) Travis – Going into optics lab
23:15 (15:15) Travis – Out of the optics lab
00:00 (16:00) Turn over to Cheryl
 

End of Shift Summary:

Title:  01/04/2015, Day Shift 16:00 – 00:00 (08:00 – 16:00) All times in UTC (PT)

Support:  Sheila, Jenne, Kiwamu,   
 
Incoming Operator: Cheryl

Shift Detail Summary: Problems with the POP_A_LF plagued the lock all morning. Went out of Observing for about an hour while Sheila and Jenne tweaked PR2. They were able to improve things a bit but it did not last for long. Finally, the recycling power dropped enough to break lock. Did an initial alignment and relocked the IFO. There were no problems with either alignment or relocking. 
   The initial alignment did make some improvements the too POP_A_LF signal. However, the POP_A_LF signal is still a bit ragged; and has been drifting downward since the lock was reestablished. It is now just below the IMC-MC2_TRANS signal.  
   The IFO is locked in Observing mode. Power is good, range is around 79Mpc. In general, environmental conditions continue to be good.   
         

H1 AOS (DetChar)
paul.schale@LIGO.ORG - posted 15:33, Monday 04 January 2016 (24691)
DQ shift 28 December - 30 December 2015

- 79% duty cycle at 75-80 Mpc, overall data looks quite clean

- a few lost locks due to earthquakes

- microseism stayed under 0.5 um/s

- no Omicron triggers for 2nd half of shift

- on Dec 28, ~20 Hz glitches occurred for most of the day, Hveto found ASC-CSOFT_Y_OUT_DQ to be responsible (possible scattering?)

full shift: https://wiki.ligo.org/DetChar/DataQuality/DQShiftLHO20151228

LHO VE
kyle.ryan@LIGO.ORG - posted 15:14, Monday 04 January 2016 (24690)
Changing frequency of CP3 over fill to every other day
We have enough data now to convince ourselves that the manually set LLCV setting supplying LN2 is nearly matching the boil-off rate 

-> Gerardo over filled CP3 yesterday -> next over fill will be tomorrow, Tuesday Jan. 5th
H1 General
jeffrey.bartlett@LIGO.ORG - posted 14:29, Monday 04 January 2016 - last comment - 16:15, Monday 04 January 2016(24687)
Lockloss - Due to POP_A_LF Drop
   Lost lock at 20:50 (12:50) due to the drop in power in POP_A_LF. Did an initial alignment and was able to relock the IFO on the first try. Back in Observing with 21.7W and 78Mpc. 

   The POP_A_LF signal is still a bit ragged and is just above the IMC-MC2_TRANS signal. 
Comments related to this report
vincent.roma@LIGO.ORG - 16:15, Monday 04 January 2016 (24693)

I'm not sure what the significance of this is, or if there is any, but I looked at the pitch and yaw signals for the various optics for today's locklosses, it seems like the ITMY optical lever pitch has behaved similarly to the H1:LSC-POP_A_LF_OUT signal, which is believed to be responsible for our recent locklosses.  I've attached two images, one for each lock today.  There are many plots shown for the various pitch and yaw signals.  The plots in the top right and bottom right are the ones I was interested in.

Images attached to this comment
H1 SUS (ISC)
brett.shapiro@LIGO.ORG - posted 22:38, Friday 01 January 2016 - last comment - 19:36, Tuesday 05 January 2016(24625)
Additional Updates to the quad Matlab model

svn up at .../SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Production

All current model features are summarized in a table in G1401132.

Update to existing features

The main change in existing features is that the top mass damping now sees both the suspension and the cage, as in real life because we use OSEMs. Consequently, if you input seismic noise to a damped suspension it will enter both mechanically as usual, as well as through the damping loops. See Seismic_Noise_Propagation_2016_01_01.pdf. Page 1 shows longitudinal transfer functions from seismic noise to the test mass with and without the OSEMs seeing the cage. The second page shows the ratio of these transfer functions. Note that the ratio is greater than a factor of 2 at 4.5 Hz. Beyond 10 Hz the maximum is about 20% at about 10.5 Hz.

 

Two new features 

1. Additional inputs and outputs added to reflect the relative nature of the OSEMs - i.e. they measure relative displacements and actuate between two points

2. Suspension point reaction forces

The discussion above is one consequence of the first new feature. Another is that you can now make transfer functions between seismic noise and the top mass OSEMs, which is dramatically different from the seismic noise to top mass transfer function. See Seismic_to_Top_OSEMs_2016_01_01-2.pdf. These are obtainable in the model with the new 'toposem' field in the 'out' structure given by the generate_QUAD_Model_Production function.

The second new feature is that there are now outputs for the suspension point reaction forces on the ISI. These are obtainable in the model with the new 'suspoint' field in the 'out' structure given by the generate_QUAD_Model_Production function. These reaction forces allow us to dynamically couple the quad model to the ISI model. Thus, if we wanted, we can make one big ISI-SUS model.

 

Under-the-hood updates

This update includes significant under-the-hood modifications to how the pieces of the model are put together. Essentially, Simulink files now define the connections and signal flow, where previously this was all done with append/connect commands in the generate script. The motivation for this change is to make the model more extensible and maintanable by humans. The append/connect commands had become virtually unreadable with the dozens of inputs and outputs now in the model. Now someone can look at a more intuitive graphical representation in a simulink file to read or modify how the model is layed out.

There are 4 simulink files defining the 4 possible layouts of the quad model:

1) A single undamped chain - generate_QUAD_SingleChainUndamped_Simulink.slx
2) A single damped chain - generate_QUAD_SingleChainDamped_Simulink.slx
3) Two undamped chains - generate_QUAD_BothChainsUndamped_Simulink.slx
4) Two damped chains - generate_QUAD_BothChainsDamped_Simulink.slx

 

For reference, this is a summary of the history of model revisions in the svn:

generate_QUAD_Model_Production.m

rev 7359: now reads foton files for main chain and reaction damping

rev 7436: Changed hard coded DAMP gains to get the correct values for LHO ETMX specifically.

rev 7508: Restored damping filter choice for P to level 2.1 filters as opposed to Keita's modification. Cleaned up error checking code on foton filter files, and allowed handling of filter archive files and files with the full path.

rev 7639: renaming lho etmy parameter file

rev 7642: Adding custom parameter file for each quad. Each one is a copy of h1etmy at this point, since that one has the most available data.

rev 7646: added ability to read live filters from sites, and ability to load custom parameter files for each suspension

rev 7652: updated to allow damping filters from sites from a specific gps time (in addition to the live reading option)

planned future revision - seismic noise will progate through the damping filters as in real life. i.e the OSEMs are relative sensors and measure the displacement between the cage and the suspension.

rev 7920: big update - added sus point reaction forces, top OSEMs act between cage and sus, replaced append/connect command with simulink files

ssmake4pv2eMB5f_fiber.m

no recent (at least 4 years) functional changes have been made to this file.

* quadopt_fiber.m

- rev 2731: name of file changed to quadopt_fiber.m, removing the date to avoid confusion with Mark Barton's Mathametica files.

- rev 6374: updated based on H1ETM fit in 10089.

- rev 7392: updated pend.ln to provide as-built CM heights according to T1500046

- rev 7912: the update described in this log, where the solidworks values for the inertias of the test mass and pum were put into the model, and the model was then refit.  Same as h1etmy.m.

* h1etmy.m

- rev 7640: created the H1ETMY parameter file based on the fit discussed in 10089.

- rev 7911: the update described in this log, where the solidworks values for the inertias of the test mass and pum were put into the model, and the model was then refit. Same as quadopt_fiber.m.

Non-image files attached to this report
Comments related to this report
brett.shapiro@LIGO.ORG - 10:37, Saturday 02 January 2016 (24638)

The quad model was tagged on the SVN both before and after this update. The tagged models are at 

before this update:
/ligo/svncommon/SusSVN/sus/trunk/Common/SusModelTags/Matlab/quadmodelproduction-rev7652_ssmake4pv2eMB5f_fiber-rev3601_fiber-rev7913_released-2016-01-01.mat
This version reflects the model after the previous recent update discussed in log 24456, which updated the test mass and PUM inertias with solidworks values. No model features were changed in this update.

After this update
/ligo/svncommon/SusSVN/sus/trunk/Common/SusModelTags/Matlab/quadmodelproduction-rev7920_ssmake4pv2eMB5f_fiber-rev3601_fiber-rev7913_released-2016-01-01.mat

The tags were created using the following script:

/ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/tagsusdynamicalmodel.m    rev 7923

jenne.driggers@LIGO.ORG - 16:32, Monday 04 January 2016 (24694)

Just as an FYI, I have done this svn update.

brett.shapiro@LIGO.ORG - 19:36, Tuesday 05 January 2016 (24717)

MInor updates and fixes:

1) The simulink files were generating warnings in Matlab 2012b because they were saved in 2013a. I resaved them in 2012b, recommited, and the problem has gone away. Matlab versions 2013a and 2015b are fine as well. No promises for versions earlier than 2012b.

2) While fixing the simulink diagrams, I added some extra inputs based on a disucssion with Brian Lantz. These are 'osem like' force inputs acting between the top mass and the cage for the purpose of testing the reaction force outputs on the ISI. These will not impact any prior features of the model.

H1 CDS
david.barker@LIGO.ORG - posted 19:00, Thursday 31 December 2015 - last comment - 11:33, Tuesday 05 January 2016(24595)
Conlog failed at UTC new year roll over

The conlog process on h1conlog1-master failed soon after the UTC new year. I'm pretty sure it did the same last year but I could not find an alog confirming this. I followed the wiki instructions on restarting the master process. I did initially try to mysqlcheck the databases, but after 40 minutes I abandoned that. I started the conlog process on the master and configured it for the channel list. After a couple of minutes all the channels were connected and the queue size went down to zero. H1 was out of lock at the time due to an earthquake.

For next year's occurance, here is the log file error this time around

root@h1conlog1-master:~# grep conlog: /var/log/syslog

Dec 31 16:00:12 h1conlog1-master conlog: ../conlog.cpp: 301: process_cac_messages: MySQL Exception: Error: Duplicate entry 'H1:SUS-SR3_M1_DITHER_P_OFFSET-1451606400000453212-3' for key 'PRIMARY': Error code: 1062: SQLState: 23000: Exiting.

Dec 31 16:00:12 h1conlog1-master conlog: ../conlog.cpp: 331: process_cas: Exception: boost: mutex lock failed in pthread_mutex_lock: Invalid argument Exiting.

Comments related to this report
patrick.thomas@LIGO.ORG - 19:53, Thursday 31 December 2015 (24597)
This indicates that it tried to write an entry for H1:SUS-SR3_M1_DITHER_P_OFFSET twice with the same Unix time stamp of 1451606400.000453212. This corresponds to Fri, 01 Jan 2016 00:00:00 GMT. I'm guessing there was a leap second applied.
david.barker@LIGO.ORG - 09:42, Friday 01 January 2016 (24605)

of course there was no actual leap second scheduled for Dec 31 2015, so we need to take a closer look at what happened here.

patrick.thomas@LIGO.ORG - 11:33, Tuesday 05 January 2016 (24708)
The previous line before the error reports the application of a leap second. I'm not sure why, since you are right, none were scheduled.

Dec 31 15:59:59 h1conlog1-master kernel: [14099669.303998] Clock: inserting leap second 23:59:60 UTC
Dec 31 16:00:12 h1conlog1-master conlog: ../conlog.cpp: 301: process_cac_messages: MySQL Exception: Error: Duplicate entry 'H1:SUS-SR3_M1_DITHER_P_OFFSET-1451606400000453212-3' for key 'PRIMARY': Error code: 1062: SQLState: 23000: Exiting.
Dec 31 16:00:12 h1conlog1-master conlog: ../conlog.cpp: 331: process_cas: Exception: boost: mutex lock failed in pthread_mutex_lock: Invalid argument Exiting.
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