After yesterday and today recentering and tweaking, the ISS second loop is back to good working condition. The first attached plot compares some signal with the second loop open and closed. Dashed line, loop open, solid lines, loop closed.

The ISS second loop signals (SUM14 and SUM58) are calibrated in volts and the whitening filter is compensated. Using the slow DC channels, I could compute the total signal for each combination, which is about 11-12 V. I used those values to calibrate the signals in terms of RIN as in the figure. This should roughly correspond to about 20 mW total power hitting the array.

The out-of-loop signal is still showing some excess noise with respect to a flat level. Assuming that there are 10 mW impinging on the four out-of-loop diodes in total, the shot-noise-limited dP/P should be sqrt(2*nu*hplanck/P) = 6e-9 /rHz. Counting both the in-loop and out-of-loop shot noise, we get an additional sqrt(2). Therefore we expect the out-of-loop signal to be at the level of 8.6e-9 /rHz, not too far from the 1e-8 /rHz that we see at about 100 Hz.

The structures between 10 and 50 Hz are variable, but I was not able to change them significantly moving the IMC alignment or the picomotors in front of the ISS array. Notably, for most of the day there was an additional bump between 10 and 20 Hz, which disappeared some time at about 13.05 local time, without any conscious intervention on my side. See second plot. No idea what the origin of this thing is, but it was there also yesterday.

One more peculiar thing. We can use IM4_TRA_SUM to measure the RIN in transmission of the IMC, as an additional out-of-loop sensor. This is included in the attached plots. When the second loop is open, the RIN measured by IM4_TRANS agrees quite well with what is measured by the ISS second loop diodes. However, when the second loop is closed, IM4_TRA measures a significantly larger noise. This might be due to the sensor electronic or dark noise (I haven't checked it yet). However, at least at 10-30 Hz it measures the same structures visible in the ISS diodes, but a factor 4 larger. The shape is also slightly different. Surprinsingly, there is no coherence between IM4_TRANS and  SUM58. This might tell us something about the origin of those peaks, but what, it's not clear.

The peaks between 15 and 25 Hz are visible, with different amplitudes and shapes, in all the eight  photodiodes, but there is little coherence among them. See third plot. These peaks are not visible in the ISS QPD signals, even though there is a wider bump at similar frequencies. They may be due to scattered light. The most prominent structure is a 18 Hz peak.

Beckhoff. Daniel and Dave

Following Daniel's changes to the Beckhoff systems, I applied the latest INI files to the DAQ and restarted the DAQ. Unfortunately h1ecatx1 needed a restart shortly after this and we have some channels disconnected. I also copied the latest Beckhoff REQ files into the appropriate target areas and Patrick reconfigured the conlog using them.

Conlog: Patrick and Dave

I modified the script which creates the conlog channel list to use the generic include.txt file as well as the generated fe_include.txt and grd_include.txt. I changed the script which generates the Guardian autoBurt.req file (which is used to create grd_include.txt) to include the USERMSG byte encode strings for conlog logging. I created a script to convert the output of USERMSG to a string. Patrick reconfigured conlog's channel list.

Guardian: Dave

I checked that the running guardian nodes and the GUARD_OVERVIEW medm screen are in sync with each other (they are). I updated the guardian autoBurt.req file (using guardctrl list to get the node listing).

Filtermodules Load Status: Dave

Many H1 models are running with partial loaded filter files. Plus two models (SUSPR3 and SUSMC2) had modified filter files. I pressed the "LOAD COEFFICIENTS" button on the GDS_TP screen for the following models to resync them with their filter files:

ISIHAM[3,4,5,6], ISIETMX, SUS[PRM,PR2,SR2,SRM,BS,ETMY,ETMX,PR3,MC2], TCSCS, LSC, LSCAUX, OMC, ASC, ASCIMC, ISC[EX,EY]. No problems were encountered.

inicheck of all DAQ INI files: Dave

I ran inicheck on all the DAQ INI files, we have channels with mixed case on the systems: ISI[BS,ITMX,ITMY,ETMX,ETMY] and LSC.

foton check on filter files: Jim and Dave

We ran foton -c on a copy of all the running filterfiles. Most of the errors we saw relate to obsolete filters left in the body of the file but no longer in the MODULES header. At some point we should make the effort to clean up the filter files of obsolete material (quak generated files exempted from a foton cleanup).

I've restarted the CDS Matlab license server to install a new license file (that is not due to expire...).  Existing sessions fail over to the Caltech servers automatically.  I'll have to update the NLM_LICENSE_FILE environment variable later to remove the old Caltech triad license servers and add the new single server configuration for failover purposes.

08:00 PSL is DOWN - sent e-mail to D Cook, P King and R Savage

08:00 3IFO team is in the LVEA

08:01 the LVEA is in the bifurcated LASER hazard state

08:15Fil, Aaron and Manny out to EX

08:30 Rick called me and walked me through restarting the PSL frontend laser.

09:00 Jody into the LVEA 

09:12 Jody ou of the LVEA

09:20 Mitchell out of th LVEA

10:10 Karen into EY

10:30 Cris into EX

10:35 Patrick and Richard working on Beckhoff system for Mids and Ends

10:36 D Barker informed me of a DAQ restart at 12:00P

10:41 Karen heading back from EY

10:53 Karen heading out to MY

11:02 Cris at MX

11:07 Patrick and Richard are done working on Beckhoff

11:35 Jeff and Andres out of LVEA - LVEA returned to full LASER hazard

11:36 Gerardo and Kyle out to LVEA

11:40 Karen leaving MY

11:50 Kris back from MX

12:04 Gerardo and Kyle out of the LVEA

12:13 DAQ restart delayed- waiting for EY update

12:21 DAQ restarted at 12:25

12:35 Fil, Aaron and Manny back from EX

13:13 HAM2,4,5 ISI WDs tripped

13:20 Travis in LVEA w/comm appr

13:22 WDs in HAM 2,4,5 reset after ISIs settled down

13:25 Dan into LVEA w/comm appr

13:53 HEPI WD accumulators cleared - HAM2 (2) and HAM5 (348) none were incrementing at the time.

13:55 CP-7 on H0VE_SITE_OVERVIEW.adl screen was alarming earlier in the day and now has remained red since right before lunch.

13:57 Travis out of LVEA

14:12 Dan into LVEA to execute LHO WP #4942

14:30 Joe into the LVEA w/comm appr - checking batteries in foklift

14:39 Sheila and Evan to End Y to investigat a problem wih the ALS

14:45 Joe out of the LVEA.

Suspension MC3 had a tripped watchdog that was brought to my attention that wasn't being reflected on the Guardian Ops Overview screen. (didn't turn red).

Summary:

Following the PR2 scan from last week (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=14845), I used a single bounce beam from IX and scanned the BS while using SR2 to center the beam on AS_C. I also scanned SR3 while using the same ASC feedback on SR2.

There's at least 0.7% or so in the SRC-AS path donwstream of SR3. Tomorrow I'll roughly center SR2 by looking at the SR2 baffle and scanning SR3, then scan SR2 to maximize AS_C while keeping AS_C centered using pico.

The beam might become off-centered on SRM depending on how well the Faraday is centered on SRM, but that should be fine.

Details:

In the first attachment, the plot on the left  is AS_C_SUM normalized VS the BS Y slider value (while the ASC loop was acting on SR2 to center AS_C).  The scan started from Y=-296.5.

As the BS Y was increased, at some point PIT feedback on SR2 became large and eventually railed the SR2 BOSEMs, and that's probably why the plot shows a kink at around BS Y=0. I had to stop the scan at BS Y=83.5. During this scan BS BOSEMs never railed. Though it's not shown here, I also scanned SR3 while using the same SR2 feedback to center the AS_C, and the data also showed similar kink.

The plot on the right is a similar plot for SR3 scan. Note that these data were taken on a different days, so the laser power could be different at sub-% level, and the IFO alignment could be substantially different, but you can see that the two plots show the same kink.

Based on the above, I'd guess that the reason why SR2 had to be moved in PIT despite YAW scan is because the centering on SRM or SR2 was poor in PIT. (Remember, ROC of SR2 is -6.4m and that of SRM is -5.7m.)

In the second attachement, I just plotted the beam displacement for the BS scan at SR3, SR2, SRM and OFI input normalized by either the beam radius (left) or optic radius (right), taking into account the fact that ASC is keeping AS_C centered using SR2. This doesn't prove anything, but suggest that SR2 and OFI are kind of dangerous as far as the clipping by the beam motion is concerned in this measurement, and we don't have to worry much about SR3.

(Note: The reason why AS_C should be centered is because the centering affects SUM number at sub % level.)

Ed reported that HAMS 2,4 and 5 all tripped at about 13:15 today. All tripped on actuators, but the spikes are small, and none of the in chamber instruments show much prior. HAM4 shows a trip that looks like something maybe hitting the chamber, so more understandable, but that trip was much later. HAM2's and 5's trips happened within 2 minutes  of each other, and look very similar. HAM2 first, then HAM5, I don't know when HAM4 happened as therehas been a subsequent trip. I've attached the HAM5 watchdog plots.

similar to last week's restart of the end stations beckhoff computers, when h1ecatx1 was restarted after lunch today the DAQ EDCU did not completely reconnect to all the channels. This is a strange reconnection event, with the EDCU code giving conflicting reports on the connection status:

daqd>
23363 channels
23335 connected
28 disconnected
74179 connection events processed
126179362 value change events processed
Total 0 disconnected.
daqd>
 

(normally the list of disconnected channel names would be given)

The number of connected channels as reported in the DAQ EPICS PVs is the total number minus 28.

Cyrus suggested we try restarting the EPICS gateway between the H1 front end LAN and the Slow Controls LAN. I did this at 14:15 but we still have 28 missing connections. I have asked the slow controls group for a copy of the Beckhoff h1ecax1 databases to see if the number 28 relates to particular epics records.

At the moment the only way to cleanly reconnect all Beckhoff channels to the DAQ is to restart the DAQ.

I've added the archive image settings to the camera MEDM, and updated the INI files to make it work.  Currently, the archiving on all cameras is disabled by setting the interval to 0.  To enable archiving, set this value to 60 to save an archive image every hour (do not use a value less than this without good reason - we don't have infinite amounts of disk space available).  Archive images are saved to /ligo/data/camera/archive/YYYY/MM/DD when enabled.

added 196 channels
removed 6 channels

Guardian user message channels are now being recorded, however the web and command line interfaces need to be updated to display them as strings instead of integer arrays.

J. Kissel

The front-end logic for calculating the IMC ODC state vector (primarily looking at IMC WFS signals) had been updated in September (see LHO aLOG 14098), but the ODC MEDM screen and EPICs records didn't get updated accordingly. 

I've svn up'd the 
/opt/rtcds/userapps/release/ioo/common/medm/IMC_CUST_ODC.adl
ODC screen, which fixed some white channels that were a result of some of the channel changes. 
Further, I've reduced the Master Gain / Trigger OK Threshold, H1:IMC-ODC_WFS_GAIN_GT_EQ_TH to 0.1 (was formerly 0.604), after recent commissioning of the WFS loops have reduced the overall WFS gain from ~0.6 to 0.2 (e.g. LHO aLOGs 14301, 13280, etc.). 

Finally, I've captured a new safe.snap (with makeSafeBackup, saved to the userapps location), ensured that safe.snap in the target area is a soft-link to the userapps location (where the front end looks for safe.snaps upon boot) and committed
/opt/rtcds/userapps/release/asc/h1/burtfiles/h1ascimc_safe.snap

The IMC is currently locked happily, and the IMC ODC now agrees. It's interesting to see that only the MC2 TRANS and IM4 TRANS SUMs are used in conjunction with the Master Gain / Trigger Threshold (as indicated by the bitmask for what is used to compute the summary bit). Why aren't we using the error points? If we don't use them we should remove them from the vector as the filter calculations are wasting computation time (though we're far from being clock-cycle limited at 28 out of 480 [usec] or 5%). 

P.S. Gabriele has now been made aware of the state vector, and will ensure that when he's finished tuning that the ODC vector will be green again.

Alexa, Evan, Nic, Jeff, Sheila

Today we changed our damping loops for ETMX and ETMY, to be more similiar to the LLO ones (Jeff's alog ).  The power sprectrum for ETMX (M0 damping filters and optical levers)  and ETMY attached.

We started by using filters similar to the Livingston design, and measuring the actuation transfer functions to both the ESD and the UIM. 

We set up the loop so that we think it should be unconditionally stable, and we have been able to get the ugf to 1.5 Hz.  The measurement agrees reasonably well with the model for the open loop. We also made measurements by injecting in the UIM lock filter bank in each arm, which can be compared to the green trace in the plot on the left in the second attachment.  The two arms match each other reasonably, and we think that our cross over is at a lower frequency than we want. 

The gains we have been able to use stably so far are 50 in the DARM filter bank, 0.4 in ETMX L1 locking and 0.67 in ETMY L1 lock, 1 in ETMX L3 lock and 1.12 in ETMY L3 lock. 

It seems like we might need to fix the oscillation in the Y arm before we can move on. 

(This is Sheila, logged in as Alexa)

UPDATED: I have added some pdfs of TFs produced by the models -- AS

Jeff B., Andres R., Mitch R., & Joe D. 

   We secured the last two suspensions in the HAM ISI Storage Container #1 this morning. After replacing the top, Bubba craned the container back over the beam tube to its parking position next to the N2 manifold. 
   
   Counts before and during work were <100 0.3 microns and larger range. After the C3 cover was put over the suspensions the counts spiked to 50 of 0.3, 320 of 0.5, and 70 of 1.0 microns. These dropped back to the normal levels within 5 minutes after the cover was secure. 

   The LVEA has been returned to full laser hazard. The cleanrooms have been turned off. The work area is ready to receive HAM ISI Storage Container #2. We will move this into place when the next group of suspensions are ready for storage.    

I spent the morning playing the picomotor game, to improve as much as possible the beam centering on the ISS photodiodes. The procedure is the same explained in 14211: I moved picomotor #8 and then used a python script to recenter the beam on the QPD using picomotor #1. My figure of merit was the sum of the power read by all photodiodes. I improved the total power by something like 0.5%, which isn't impressive, but at least now I know that I'm very close to a maximum. For future reference, the total sum of all PD signals, in counts, as measured by the IOP-PSL0_MADC1_EPICS_CH24-31, is about 40050.

After this, I injected a 1 Hz line on IM3 pitch and then yaw, and looked at the variation of the PD powers. I moved a bit the beam with both picomotors, to reduce the oscillation that was clearly visible only in PD2 and PD4. Now I'm close to be dominated by the two omega oscillation in both diodes. The optimal position does not correspond to a exactly centered QPD: PIT = -0.06, YAW = 0.35. Note that PIT and YAW for the QPD are reversed with respect to PIT and YAW for IM3!

Then, I took some (medium) high resolution spectra of all PDs, to estimate the coupling of beam motion to RIN. I used a IM3 pitch excitation at 1 Hz, with an amplitude of 300 cts. This gives me a signal on the QPD of 0.67 1/rHz, corresponding to 105 um/rHz. I used the same frequency for yaw, but with an amplitude of 200 cts, corresponding to 0.80 1/rHz on the QPD or 125 um/rHz. Spectra of all signals are shown in the attached figures.

Here are the results:

In general, those numbers are not too much different from the best we could get in the past. The only exception is PD4, which looks quite bad.

From all of us at LHO, a hearty congratulations to Kiwamu and Rie Izumi, celebrating the 0th birthday of Hana Izumi (和泉はな)! 

* * *
Birth date: Nov.1st
Height: 19.5 inches
Weight: 6lbs 5oz
* * *

There's a huge 364Hz line in ALS TRY.

I'm not sure if this was already there for a while. Though we probably changed the loop gain of the ALSY PDH loop when we realigned the green path on ISCTEX today.