There was a report of GPS glitch as large as 13 microsec (http://www.itnews.com.au/news/satellite-failure-caused-global-gps-timing-anomaly-414237) starting around "January 26 12.49 am local time", presumably Mountain Standard Time, so it's probably around Jan 26 07:49 UTC, and was fixed by "6.10 am Mountain Standard Time".

I looked at the timing comparator for the cesium clock (H1:SYS-TIMING_C_MA_A_PORT_2_SLAVE_CFC_TIMEDIFF_1) as well as X end GPS receiver (H1:SYS-TIMING_X_FO_A_PORT_9_SLAVE_CFC_TIMEDIFF_3) and Y end GPS (H1:SYS-TIMING_Y_FO_A_PORT_9_SLAVE_CFC_TIMEDIFF_3).

(It seems like end station GPS units are connected to the second input of timing comparators at each end station at LLO, but here they are to the third input.)

Right plot shows 6-days, and the left one is 4 hours around the reported glitch, and I see no timing jump.

State of H1: locking but not making it to DRMI_Locked

Summary:

• morning work in the LVEA pulling cables to racks near HAM6 - finished at 11AM
• H1 has been aligned from an initian alignment
• DRMI is locking but cannot reach DRMI_Locked
• ISI filter changes reverted in BS and ITM chambers
• dark offsets set for ASAIR and POPAIR, which was necessary after the rack work at HAM6
• Environmental: useism is 0.7um/s and winds are below 10mph

We are pretty sure this added motor is a non issue as far as noise goes.  But, I'll let this run for a week before the configuration changes.  It is running under servo control and the level switch functions so it should shut itself off should a bad leak occur.  I have a nuisance drip on one of the hoses but am capturing that.

Otherwise, if you are in the Mechanical Room and see some major problem at the flushing stand, just hit the red button on the North facing enclosure cabinet.

Re WP 7505

Making these gains unity greens the hardcoded medm making the state of the ISI look better by reducing the reds seen on the Overview screens.  There are still other reds seen in Sensor Correction and Blend sections of the Overview but greening or graying these out will be more of an medm programming pain.  I'm not sure I'll be able to 'fix' these...

The foton files have been committed.  I've acceptted the changes in the SDF OBSERVE.snaps (down.snap for the BS.)  I still need to accept these for the safe.snaps & the BS OBSERVE.snap.  I'll complete that after the meeting currently attending.

Meanwhile--Let's not restart any ISI FEs.

After months of 24/7 work, had an opportunity to gather a majority of the LHO Operator Team during our Ops Meeting (Jim is photoshopped in since he was working as Commissioning Help during the evenings this week).

Thank you for all your work!

FYI - I've been holding off on taking the ETM charge measurements since Cheryl has been hard at work to relock both yesterday and now today.  We assume it is better to keep plugging away at lock recovery since we've been on a dry spell for a few days.  We'll continue to look for an hour of dead time today through Tuesday.

The cooling system for the H-2 electronic building was repaired yesterday, (see FRS 4271), and is functioning correctly.

The TCS AOM drivers had tripped. To reset them, I turned the AOM driver power supply (mezzanine in the mechanical room) off and then on again.

As much as I enjoyed the walk ou there, we need to be able to do this remotely.

Day Ops: 16:00-23:59UTC (08:00-16:00PT)

State of H1: unlocked, locking and making past DRMI, but not to Low Noise

Shift Summary:

Work Today:

• HAM6 - invasive work on cables and moving electronics
• crane shim work West Bay of the LVEA - sledge hammers were involved
• ESD driver cable swap - minor incurrsion, no effect on the drivers, drivers were not powered off/on
• TCS activities outside of the TCS tables
• Kyle worked on a pump at EX, a stiuation that just came up this morning, he also went to Mid-Y
• JeffB visited EX and EY
• Bubba and a vendor went down the Yarm
• Ed and I filled the PSL chiller with 100ml of water (top chiller, bottom chiller is not complaining that it needs water)
• EX and EY blend filters changed from Quiet 90s to 45mHz, X direction at EX and Y direction at EY

Issues encoutered today - locking the X arm in IR:

• I tried and Evan tried, and it did not lock
• yesterday some X arm locking issues as well, but the arm locked up after Sheila opened some MEDMs, even though she did not change anything
• higher gain, lower gain, sign change for gain, all were no help today
• alignment was clearly good, though maybe there's more to consider than the height of the spikes when locking, but routinely the spikes were 0.95 and above

Environmental deturants to locking:

• useism is at 1.0um/s in the Corner Station
• high winds between 25 and 35mph for about one hour
• winds above 15mph for about 2 hours

The HgCdTe photodiodes on the TCS CO2 laser tables have had their calibration updated.  The outputs are now calibrated in volts at the PD.  I've stored the new calibrations in filter banks, such that both filters need to be turned on to get correct calibration of the channel and no other gain needs to be set.

The DC inputs have:

Filter 1) Convert from counts to volts

Filter 2) Divide by gain of 510 to give voltage at the photodiode

The AC inputs have:

Filter 1) Convert from counts to volts

Filter 2) De-whiten signal.  Initial whitening is AC coupled with a pole at 20Hz and a high frequency gain of 105dB.  We have reversed this with a filter that has high frequency gain of -105dB, a zero at 20Hz and a pole well below any frequency we care about at 0.01Hz (we didn't put the pole at 0Hz because we don't want this thing integrating continuously).

[Alastair, Aidan]

Attached are some plots of RIN for the X and Y arm lasers.  There are now channels in the front end for RIN for in loop and out of loop photodiodes on each table.  Here we show the RIN and dark noise for both lasers.  The in loop photodiode for the Y-arm table is giving zero response so either there is a problem with it or the beam is mis-aligned.  I've only attached the data for the other 3 diodes.

The dark noise is consitent between all three diodes.  The RIN of the X-arm laser is approx 5x10^-7 at 20Hz.  The Y-arm laser is higher at 2x10^-7.  The Y-arm result is similar to the best we measured at Caltech (also attached).  It may be that the X arm is lower than we have previously measured due to the low noise enviroment.  The spectrums show no excess at low frequency such as would be attributed to air motion on the table, which is good news.  Also the in loop and out of loop diodes on the X-table show very similar spectrums which is good for any future intensity noise cancellation.

Moved electronics to reflect new rack layout for ISC-R3 per D1001426-v10. This is to allow spacing for the new 2 omega auto-centering electronics. Work consisted of moving chassis a few U slots in the rack. All electronics remained on, and no cables were disconnected. Work will continue tomorrow to run field cables from CER to HAM6 racks. This will involve working over HAM6.

Fil C. & Ed M. & Daniel S.

0915 -0955 hrs. local -> To and from X-end 

Pump won't start on either HV channel, gets to 500V then limits at 500ma -> Tempted to increase the default arc limit of 10 per minute but will consult with GammaVacuum first

H1 has 30 sender RFM channels on each arm, of which only 26 have corresponding receiver(s). So 4 are being sent and no model is using the data.

L1 has 29 senders on the X-ARM (of which there are 26 receivers), and 30 senders on the Y-ARM (of which there are 26 receivers).

So the two sites are very close in number of sending channels.

Analysis details: The base number of potential senders was derived from the main IPC file, looking for RFM0 and RFM1 ipc types. This resulted in 30 for H1-X and H1-Y, and 42 for L1-X and L1-Y. Because the ipc file is only appended to during compilation, if it has not been cleanly regenerated recently it may overcount the number of sending channels.

For each channel, I searched the models' RCG generated IPC_STATUS.adl medm file for the channel name (e.g. H1LSC_IPC_STATUS.adl). Assuming that no two ipc channels share the same name, if I found the channel name in the adl file this means it is a running sender with a receiver. For the remaining possible senders without receivers (H1-X=4, H1-Y=4, L1-X=16, L1-Y=16) I looked for the channels in the top level simulink source files (e.g. /opt/rtcds/userapps/release/*/l1/models/l1*.mdl). This showed that all four channels on H1-X and H1-Y do have sending models, and for L1-X 3 of the 16 had sending models, and for L1-Y 4 of the 16 had sending models.

If we can possibly remove some of the RFM channels which are not being received, additional RFM channels can be added to the loop with no risk.

For H1 the sending channels with no receivers are:

• H1:OAF-PEME[X,Y]_RFM
• H1:ASC-[X,Y]_TR_A_SUM_RFM
• H1:ALS-[X,Y]_ARM_RFM
• H1:ALS-[X,Y]_REFL_B_LF_RFM