One of the things that is slow and not optimized well about our inital alingment is the lock of the laser to the Xarm.  This is not a hard problem, just one that we have never taken the time to work on.  This was one of the problems (annoyances) that the relocking team ran into this afternoon.  I had a look at the data from a sucsessfull acquisition, and can see two problems that have simple solutions. 

1) It takes too long to ramp down the feedback from the IMC locking loop.  We have a 3 second pause and a 2 second ramp on this gain.  While both loops are on, they fight each other and the lock is unstable (see attached screenshot).  I would suggest something like a half second for each of these, or even less. 

2)We had a 0.1 second delay on the FM triggering that turns on boosts.  The other day I had reduced this from 0.2, but it is still too long.  We should probably try a shorter FM delay or no delay.

J. Kissel, D. Barker

The state of the H1PSLISS.txt foton file was in a state of confusion. A diff between the last several back ups, shows very small changes (the 14th significant digit) to the gain coefficient in about 12 filter modules. Sudarashan ensures use that he's only been making changed to the 
ISS_SECONDLOOP_SUM14_DC
ISS_SECONDLOOP_SUM58_DC
filter banks, yet there are these small changes to several filter modules in the following banks reported over the past few backups:
ISS_SECONDLOOP_QPD_SUM
ISS_PDB_LSD_INTEGRATION
ISS_PDB_LSD_BANDPASS
ISS_PDB_CALI_AC
ISS_OSCILLATION_MON_LP

We don't understand it, and we can't trace it. However, because the changes in the uncertain filter banks appear to all be small, we've decided to just "start from scratch" and load the whole filter en masse.

So, the current archive, in 
/opt/rtcds/lho/h1/chans/filter_archive/h1psliss/
H1PSLISS_1123967724.txt
represents the currently loaded filter coefficients. Further, the current filter file, in
/opt/rtcds/lho/h1/chans/H1PSLISS.txt

which is a soft link to the userapps, 
/opt/rtcds/userapps/release/psl/h1/filterfiles/H1PSLISS.txt
has been committed to the userapps repo.

Kiwamu, Hang

We investigated the nonlinearity in the esd control signal using channel 'SUS-ETMY_L3_MASTER_OUT_UL_DQ'. In the upper panel of the attached plot, the 'linear' is the product of control signal and the bias, 'quadratic' the square of control signal, and 'total' the sum of these two. We did not do an absolute calibration but the relative magnitude should be good enough for the purpose of this study. In the lower panel we showed the coherence between the linear and quaduartic timestreams, with 512s of data and 64 averages.

From the result we can see that the nonlinear term is well below the linear component, and the coherence was low. As a result, it should be safe to use the current ESD configuration without worrying too much about the quadratic term.

Mid maintenance, the ETMy ESD tripped off.  I toggled the HV ON/OFF switch on the SUS screen which tunred it on, but in the railed ~-16k state.  I toggled the switch slowly a few times but the railing never cleared.  Richard went to EY and did the old "Power OFF, pull DAQ plug, re-power ON, re-plug in DAQ cable" trick.  It's back now.

J. Oberling, P. King

PMC Alignment

After the last week's temperature spike the transmitted power through the PMC had dropped (see alogs 20490 and 20504), today's goal was to fix it.  First Peter attempted to adjust the temperature of the PMC, as it had not settled back to its original temperature from before the temp spike.  See Peter's alog here for full details, but the short version is that temperature is such a slow actuator and we are so limited on time that we decided to go in and adjust the beam alignment into the PMC.

With the ISS off we tweaked mirrors M06 and M07.  Pitching M06 down slightly gained us the lost PMC transmission.  Walking the beam slightly up and down in pitch and left and right in yaw did not improve the transmitted power, so after re-locking the adjustment screws we had:

• PMC_TRANS: 25.2 W
• PMC_REFL: 1.8 W

We checked the centering on the PMC_TRANS PD and after a very slight adjustment to mirror M36 the transmitted power increased slightly to 25.29 W.  We measured the visibility of the PMC:

• Unlocked: -1.51 V
• Locked: -0.129 V
• Visibility: 14.6%

With the ISS on:

• PMC_TRANS: 25.1 W
• PMC_REFL: 1.79 W

We then measured the transmitted PMC power and the power after the ISC EOM with a power meter.

• PMC transmission: 25.0 W
• After ISC EOM (after IO_MB_WG1): 23.6 W

The power out of the ISC EOM is displayed on the IMC Overview MEDM screen, in the lower left corner.  On the PSL table this is IO_AB_PD3.  It read 25.81 W, so this needs recalibration.  We blocked the PD and saw 0.175 W on the MEDM screen, so there is some offset we need to remove as well.

O1 Prep

We turned off all the computers inside the enclosure and removed the 1 cordless phone (it is currently sitting on the desk on the west side of the H1 PSL enclosure next to the PSL electronics rack).  We shut off the DBB electronics in prep for O1; these will need to be turned back on if we want to run DBB scans during Tuesday maintenance.  Once done in the LVEA we asked Richard to turn off power to the clean room phone located in the PSL enclosure.  All HEPA fans for the enclosure are off, as well as both air conditioners.  The make-up air is set to 20%, and this was confirmed by listening to the fan (it is located in the old chiller closet on the east side of the H1 PSL enclosure).

IO_AB_PD3 Recalibration

J. Oberling, P. King, C. Vorvick

We recalibrated IO_AB_PD3.  To remove the measured 0.175 W of offset we set the offset value on the filter screen to -77.0 (440 counts/W with a gain of 1).  We then set the gain to 0.916 to get the MEDM window to match our power measurement.  If we want more power from the PSL our only course now is to increase the front end diode currents.

just when we thought we had fixed the monit autostart of the daqd process on h1dc0 it again failed to start up after a DAQ restart this morning (following model changes). Using the monit web page, I was able to stop and start the daqd process manually. I verified there were no duplicate processes running and the PID file was correct. There is a DAQ frame gap due to this problem from 09:13 to 09:51 PDT (between GPS times 1123949568 - 1123951808).

Charge measurements was done on both ETMs.
It is early enough to discuss the new tendencies, nevertheless it seems like ETMY change the sign of charging after changing the bias sign on ETMY (see 20387) while ETMX charging is the same (as well as the bias sign).
Now (since Aug,10) both ETMX and ETMY Biases are -9.5V, 
Plots are in attachment.

After the QUAD front end restarts, we found that some of the DARM DAMP MODE loops were blasting the suspension.  In these cases, the FE was restoring non-zero gains as per the safe.snap settings file.  Since Jenne confirmed that the GUARDIAN sets these gains and turns these loops on, I have written all of the gains to be ZERO in the safe.snaps for future restarts.

as part of the SR3 investigation, we restarted the h1iopsush56 model to re-calibrate the 18bit DACs. The procedure was: stop user models, stop IOP model, start IOP model, check the status of the 18bit DAC autocal, clear the SWWD DACKILLs to stop the SEI SWWD countdown, start the user models one at a time.

Looking at the AUTOCAL history, this restart and the previous 3 restarts since the last reboot have all successfully calibrated all 5 DAC cards in the correct amount of time.

following the h1susetm[x,y] model changes this morning to remove the cpu intensive violin mode calculations from the models, the models are now running faster. Looking at second trends over the past few hours, the CPU max ranges before and after the change are shown below

the improvement is in the range of 3uS to 4uS. The TIM bit of the STATE_WORD triggers above 62uS, so we would not expect any more TIM errors on the CDS overview screen.

ER8 day 1

no restarts reported.

Filiberto, Richard, Elli

A filter was added to the HWS power supply.  The idea is that the filter module will cut out the current spikes from the HWS that were showing up in the PEM channels.  We will test this today.

The filter is in a box labeled "HWS filter for power supply" and is located inside the HWS table by HAM 4, on top on the HWS corner breakout box.  The filter connects between the HWS Corner Breakout Box (refer to D1200934 and E1100892).

This morning after we restarted the ITM and ETM SUS models, the guardians failed when attempting to bring these SUSes back up.  It failed on all 4 QUAD SUS guardians at the same place when requesting to go from SAFE to ALIGNED:

2015-08-18T15:47:25.63598 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L2_TEST_L => ON: OUTPUT
2015-08-18T15:47:25.88943 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L2_TEST_P => ON: OUTPUT
2015-08-18T15:47:26.14962 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L2_TEST_Y => ON: OUTPUT
2015-08-18T15:47:26.40621 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L3_TEST_L => ON: OUTPUT
2015-08-18T15:47:26.65966 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L3_TEST_P => ON: OUTPUT
2015-08-18T15:47:26.91415 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L3_TEST_Y => ON: OUTPUT
2015-08-18T15:47:27.16605 SUS_ETMX [ENABLE_ALL.main] ezca: H1:SUS-ETMX_L3_TEST_BIAS => ON: OUTPUT
2015-08-18T15:47:27.16619 SUS_ETMX [ENABLE_ALL.main] Turning on OL damping outputs
2015-08-18T15:47:27.18074 SUS_ETMX W: Traceback (most recent call last):
2015-08-18T15:47:27.18076   File "/ligo/apps/linux-x86_64/guardian-1485/lib/python2.7/site-packages/guardian/worker.py", line 459, in run
2015-08-18T15:47:27.18077     retval = statefunc()
2015-08-18T15:47:27.18077   File "/ligo/apps/linux-x86_64/guardian-1485/lib/python2.7/site-packages/guardian/state.py", line 240, in __call__
2015-08-18T15:47:27.18078     main_return = self.func.__call__(state_obj, *args, **kwargs)
2015-08-18T15:47:27.18078   File "/opt/rtcds/userapps/release/sus/h1/guardian/SUS.py", line 456, in main
2015-08-18T15:47:27.18079     sus.olDampOutputSwitchWrite('ON')
2015-08-18T15:47:27.18079 NameError: global name 'sus' is not defined
2015-08-18T15:47:27.18080
2015-08-18T15:47:27.18762 SUS_ETMX ERROR in state ENABLE_ALL: see log for more info (LOAD to reset)

Reloading the GRD didn't work.  In order to get around this we Put the GRD to MANUAL and enabled the output switches by hand, then selected ALIGNING, anmd ALIGNED. 
 

Evan, Dan, Jeff

The SR3 M1 T2 actuator is...unwell.

We started to have trouble staying locked after power up about four hours ago.  At first it looked like an ASC problem in the SRC, and since the AS36 loops are the scapegoat du jour, Evan started to retune the SRC1 loop.  He observed a recurring transient in the beam spots at the AS port, and saw the same thing in the SR3 oplevs.  We turned off the SR3 cage servo and the kicks kept on coming.

Eventually we looked at the SR3 M1 voltmons and found the first plot attached, which is for eight hours.  The T2 OSEM and voltmon started to get ratty about three and a half hours ago.  The noise is a series of slow transients with a several-second rise and a steep decay.  See Fig. 2.

We're pretty convinced that it's an actuator problem, something between the DAC and the voltmon readback in the coil driver box.  We have unlocked the IFO and turned off the SR3 top-stage damping and we still see the pattern of noise.  We shall leave the pleasure of power-cycling the AI chassis and coil driver to others.

As an amuse bouche for the maintenance day team, we also discovered that the SR3 M1 T1 voltmon is complete nonsense.  The T1 voltmon time series is a collection of step functions and spikes, 100x larger than the other M1 voltmons.

The SR3 M1 damping has been turned back on.

H1 now in OBSERVATION MODE

As per LIGO-M1500250, H1 has now been put into "OBSERVATION MODE".  This means:

The ODC-OPERATOR_OBSERVATION_READY bit, which is set to "Undisturbed" by the operator on the GUARD_OVERVIEW screen, will now be automatically unset by the Guardian IFO top node if any of the monitored guardian nodes drop from OK==True.

The most likely ways that this can happen are:

• Lock loss
• SUS or SEI watchdog trip
• TCS laser trip
• Change of state or operational mode of any Guardian node (e.g. OP, MODE, REQUEST, or ERROR change)

Operators must be aware that the INTENT bit must be manually reset after any of these changes.

The list of Guardian nodes being monitored is stored in:

USERAPPS/sys/h1/guardian/IFO_NODE_LIST.py

The current monitored node list is:

ALIGN_IFO
ALS_COMM
ALS_DIFF
ALS_XARM
ALS_YARM
HPI_BS
HPI_ETMX
HPI_ETMY
HPI_HAM1
HPI_HAM2
HPI_HAM3
HPI_HAM4
HPI_HAM5
HPI_HAM6
HPI_ITMX
HPI_ITMY
IMC_LOCK
ISC_DRMI
ISC_LOCK
ISI_BS_ST1
ISI_BS_ST2
ISI_ETMX_ST1
ISI_ETMX_ST2
ISI_ETMY_ST1
ISI_ETMY_ST2
ISI_HAM2
ISI_HAM3
ISI_HAM4
ISI_HAM5
ISI_HAM6
ISI_ITMX_ST1
ISI_ITMX_ST2
ISI_ITMY_ST1
ISI_ITMY_ST2
OMC_LOCK
SEI_BS
SEI_ETMX
SEI_ETMY
SEI_HAM2
SEI_HAM3
SEI_HAM4
SEI_HAM5
SEI_HAM6
SEI_ITMX
SEI_ITMY
SR3_CAGE_SERVO
SUS_BS
SUS_ETMX
SUS_ETMY
SUS_IM1
SUS_IM2
SUS_IM3
SUS_IM4
SUS_ITMX
SUS_ITMY
SUS_MC1
SUS_MC2
SUS_MC3
SUS_OM1
SUS_OM2
SUS_OM3
SUS_OMC
SUS_PR2
SUS_PR3
SUS_PRM
SUS_RM1
SUS_RM2
SUS_SR2
SUS_SR3
SUS_SRM
SUS_TMSX
SUS_TMSY
TCS_ITMX

Craig, Jenne, Kiwamu,

We did a VCO calibration for the ALS diff vco in the last Friday when the interferometer was suffering from high wind. The new result suggests that the VCO calibration stays the same as the one for ER7 by 0.6%.

The new coefficient is 0.11847  +/- 9.3e-05  [cnts @ DIFF_PLL_CTRL_INMON / Hz @ DIFF VCO frequency read by the timing comparator ].

The attached below shows the fitting result:

The measurement method is the same as the previous one which is described in this alog (alog 18711). One difference is that we used the INMON as opposed to OUTPUT because we did not want to rely on the filter shape of the chain which contains the zpk([[40], [1.6]) which is supposed to cancel the low noise VCO circuit. The sweep was as slow as 255 [Hz/ sec]. The fitting uses a frequency region where the linearity was found to be good (as indicated in the plot as yellow shaded region).

The analysis code, data and figure are saved in SVN as follows:

/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/ER8/H1/Scripts/ALSDiff/vco_calibration_fitting.py

/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/ER8/H1/Measurements/ALSDiff/2015-08-14_vco_sweep_v2.txt

/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/ER8/H1/Results/ALSDiff/2015-08-14_VCO_calibration_v2.pdf

/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/ER8/H1/Results/ALSDiff/2015-08-14_VCO_calibration_v2.png