ELOG 40m

MC Servo Board offset gone bad!

Electronics

The attached plot shows that someone broke the MC_SUM_MON channel around 10:30 AM this past Wednesday the 11th. This is the EPICS monitor of the MC error point.

Come forward now with your confession and I promise that I won't let Steve hurt you.

Attachment 1: mcoff.png

1316

Tue Feb 17 05:20:11 2009

Since we excluded *.snap and *.req files from the svn control in the medm directory and these were not restored by the svn co, the burt part of the align/mis-align scripts were not working correctly this evening. So I recreated .req files and cooked up some mis-aligned .snap files.
After some cut-and-try work, I was able to run the dither alignment scripts fine.

Due to the above mentioned delay, the locking work started around midnight.

Tonight, the DD hand-off was not robust. I spent sometime to optimize this.
After the optimization, the locking proceeded to the DC CARM/DARM control state stably.
The CARM->MCL hand-off failed because the LSC-MC offset button was off.
I added a line to turn on the button in the ontoMCL script.
Today, the offloadMCF script worked fine.

Next, the cm_step script stumbled on the "ENGAGERIZING" of the AO path.
I got a hunch that the AO path might not be connected to the MC board.
Indeed, OMC_OSC_FM was connected to the IN2 of the MC board. Looks like it was used for the optimization of the modulation frequencies.
Probably I had the hunch because I did it Smile

I was able to increase the arm power up to 3.9.
The script failed when it tried to switch the CARM signal from TR_DC to SPOB_DC.
I haven't tackled on this issue yet.

1317

Wed Feb 18 03:17:40 2009

Yoichi, Kakeru,

Last night, the cm_step script failed at the hand-off of CARM error signal from TR_DC to PO_DC.
This was fixed by reducing the PO_DC gain by a factor of 2.
Currently the script fails when changing C1:LSC-DEMOD_GAIN to zero.
To be honest, I don't fully understand the purpose of this step.

1318

Wed Feb 18 03:25:25 2009

I restored the medm directory from the backup on the tape.
The directory had an svn property svn:ignore set and the value of the property included *.snap and *.req.
This resulted in the exclusion of those files from the repository.
I fixed this problem by changing the property of all the directories under /cvs/cds/caltech/medm.
After fixing several other svn problems, the current medm directory contents were checked in to the repository.

1319

Wed Feb 18 15:31:38 2009

emergency back-up lights checked

Bureaucracy

SAFETY

All 13 exit and emergency back-up lights and their batteries were checked.

Two of the batteries were replaced.

1320

Wed Feb 18 19:13:20 2009

SVN & MEDM & old medm files

Allegra had a 2 year old version of SVN installed and CentOS (yum) couldn't upgrade it, so I did an 'svn remove subversion'
and then a 'svn install subversion' to get us up to the Dec '08 version (1.5.5) which is the latest stable.

I also removed all of the old ASS medm directories without backing them up. There's a new RCG script version which is
fixed so that it no longer dumps these old medm directories in there; there's no need since there's already an
medm archive area.

I also removed the medm/old/ directory, did an svn remove, and then copied it back. This is the only way I know of
removing something from the repository without removing it from the working directory.

1321

Wed Feb 18 21:03:22 2009

ETMY Camera work not elogged!

Cameras

The control room video is showing us a false ETMY image. Who worked on the ETMY camera or video today??!!

1322

Wed Feb 18 21:10:21 2009

MC Drumhead mode lost again

IOO

In early December, Caryn and I noticed that the MC Drumhead mode was visible at the Qmon point of
the MC demod board using a spectrum analyzer and no external excitation of the MC mirrors. We then
started tracking the MC Drumhead modes.

Today I found that it is gone again. It also wasn't there when I looked for it in 2007. Mad

I looked at the MC error point spectrum and it seemed reasonable. Changing the gains in the MZ, ISS, PMC, & FSS
had no good effect on the noise spectrum.

The voltage noise above 10 kHz in the MC error point is increasing like ~f. I think that this means that
the leftover is the noise from the FSS. Below 10 kHz it is the noise of the VCO (10 mHz/rHz).

One possibility is that the high frequency noise changes with the mood of the NPRO. There should be no
frequency noise induced by the decay of the PA diode power. We can do an NPRO SLOW scan to see if there
is some kind of mode hop noise happening.

1323

Thu Feb 19 04:16:17 2009

Rob, Yoichi

We checked the CM-MC cross over just before turning off the moving zero.
There was a slight bump in the gain of the MC_L loop at (I believe) the optical spring freq. (~400Hz) just below 0 dB. The phase margin there was very thin.
Removing the moving zero will increase the bump more and make the loop unstable.
Rob suggested to increase the AO gain a bit more.

To see if the AO path is really working, I connected the OUT2 of the MC board to a spare DAQ channel (C1:PEM-OSA_APTEMP).
I confirmed that the PO_DC signal is actually coming to the AO path input of the MC board.
I also hooked up the SR785 to the A excitation channel of the common mode board, so that we can measure the loop gain of the AO path.
After these preparation, the lock acquisition process became somewhat unstable. The ifo loses lock randomly at various places in the lock acquisition steps.
So, as of 4:00 am, I have not gotten a chance to try Rob's suggestion nor the TF measurement with SR785 yet.
I will continue the work tomorrow (i.e. tonight ??).

1324

Thu Feb 19 11:51:56 2009

HTEMP variation is too much

MOPA

The C1:PSL-MOPA_HTEMP variation is more than 0.5 C daily

Normally this temp stays well within 0.1 C

This 80 days plots shows that we have just entered this unstable region some days ago.

The control room temp set unchanged at 70 F, actual temp at ac-mon 69-70 with occasional peaks at 74 F

Water temp at chiller repeatedly around 20.6 C at 8 am

This should be rock solid at 20.00C +- 0.02C

Attachment 1: 80dhtemp.jpg

1325

Thu Feb 19 16:29:43 2009

Martian wireless router bad

The Martian wireless router is dead.
I rebooted it several times, but it hangs up in a minute.
I will ask steve to buy a new one.

1326

Thu Feb 19 22:40:33 2009

I checked a broken QPD, which was placed for PSL angle monitor, and finally I cocluded one segment of the quadrant diode was broken.

The broken segment has a offset voltage of -0.7V after 1st I-V amplifier. It means the diode segment has a current offset without any injection of light.

Tomorrow I will check a new QPD for replacement.

Kiwamu IZUMI

1327

Thu Feb 19 23:50:31 2009

pete

aligned pd's on AP table

Yoichi, Peter

While continuing our efforts to lock, we noticed the procedure failed at a point it had gotten past last night: turning on the bounce/roll filters in MICH, PRC, and SRC. We checked the MICH transfer function and noticed that the unity gain point was ~10 Hz, well below the bounce modes. We tried increasing the gain but found saturation, and Rob suggested that there could be misalignment on the AP table, which Steve worked on today. We went out and found two of the PDs (ASDD133 and AS166) to be badly misaligned probably due to a bumped optic upstream. We re-aligned.

1328

Fri Feb 20 01:54:18 2009

Kakeru

Computer Scripts / Programs

tdsdata might have a bug

I found a strange jump of value in my data taken with tdsdata.
I couldn't find same jump in a playback of DataViewer, so I think this is a problem of tdsdata.
Be careful when you use tdsdata!

The attached file is an example of jumped data.
I try to get data with allegra and op440m, and both has same kind of jump.
(A downsampling or interpolation may be wrong.)

Rana said there is a fixed version of tdsdata in some PC, but 64bit linux may not have.
I try it tomorrow.

Attachment 1: jumped_data.png

1329

Fri Feb 20 03:52:23 2009

Yoichi, Peter

Tonight, we had a problem with the DD hand off.
It failed when the RG filters of MICH for the bounce-roll modes are engaged.
The reason for the failure was that the MICH UGF was too low (~10Hz).
As in the Peter's elog entry, we found that the AS PDs are mis-centered.
Even after we fixed the centering, the MICH UGF was still too low. So we increased the MICH feedback gain by a factor of 10.
The reason for the gain decrease is unknown. It seems almost like the BS coils get weaker.
I checked the UGF of the BS OL loops. These are around 4Hz, so fine. We should check the HWP on the AP table tomorrow.

After the DD hand-off goes ok, the switching of DARM signal from DC to RF failed.
I found that the gain and the polarity of the RF signal were wrong.
AS166 is one of the PDs we found mis-centered (and re-centered). But how can you flip the sign of the signal ?

After this, the cm_step script goes until the activation of the moving zero, but fails when the arm power is increased to 0.7.
Also the ontoMCL script succeeds only 50% of the time.

1330

Fri Feb 20 19:31:16 2009

LSC

MICH low gain problem

Last night, we found that MICH UGF was too low. Even after re-aligning the PDs, it was still too low.
Today, I compared the UGFs of MICH and PRC when in the DRMI configuration locked with the single demod. signals.
In this configuration, MICH signal comes from REFL33Q and the PRC signal comes from REFL33I (the same PD).
The PRC UGF was about 100Hz whereas MICH was only ~10Hz.
Since they uses the same PD, the low gain is not caused by the PD.
I checked conlog history and confirmed there is no change in the MICH->BS path in the last few days.
I also checked the svn history of chans directory for changes in filters. Nothing problematic found.

Then I noticed that the susvme computers were overloaded.
This time, I rebooted all the FE computers just in case.

Then the MICH gain was somewhat recovered (by a factor of 3 or so). Don't know why.

I adjusted the DD_handoff script to set the MICH gain to 0.7 before the bounce-roll filter is engaged.

1331

Sun Feb 22 23:43:07 2009

Comparing PSL-FSS-RMTEMP and PEM-MC1-TEMPS

So, to compare temp channels, I made a plot of PSL-FSS_RMTEMP and PEM-MC1_TEMPS(the test temp sensor channel after converting from cts to degC). This plot begins about 2 months ago t_initial=911805130. The temperature channels look kinda similar but MC1-TEMPS (the temp sensor clamped to MC1,3 chamber) is consistently higher in temperature than FSS_RMTEMP. See compare_temperature_channels.png.

MC1-TEMPS isn't exactly consistent with FSS-RMTEMP. I attached a few plots where I've zoomed in on a few hours or a few days. See compare_temperature_channels_zoom1.pdf & compare_temperature_channels_zoom2.pdf

Change the room temperature, see what happens to the chamber temperature

A while ago, somebody was fiddling around with the room temperature. See compare_temperature_channels_zoom4.pdf. This is a plot of PEM-MC1_TEMPS and PSL-FSS_RMTEMP at t0=911805130. You can see the chamber heating up and cooling down in happy-capacitory-fashion. Although, the PSL-FSS_RMTEMP and the PEM-MC1_TEMPS don't really line up so well. Maybe, the air in the location of the MC1,3 chamber is just warmer than the air in the PSL or maybe there's an offset in my calibration equation.

Calibration equation for PEM-MC1-TEMPS

For the calibration (cts to degC) I used the following equation based on the data-sheet for the LM34 and some measurements of the circuit:

TEMPERATURE[degC]=5/9*(((-CTS/16384/451.9/1.04094)-(.0499*10^-3))/(20*10^-6)-35);

How does the chamber temperature compare with the air temperature?

It looks like the chamber may be warmer than the air around it sometimes.

I wanted to check the temperature of the air and compare it with the temperature the sensor had been measuring. So, at t=918855087 gps, I took the temp sensor off of the mc1-mc3 chamber and let it hang freely, close to the chamber but not touching anything. See compare_temperature_chamber_air.png. MC1_TEMPS increases in temperature when I am handling the temp-sensor and then cools down to below the chamber temperature, close to FSS_RMTEMP, indicating the air temperature was less than the chamber temperature.

When, I reattached temp sensor to the chamber at t=919011131 gps, the the temperature of the chamber was again higher than the temperature of the air. See compare_temperature_air2chamber.pdf.

Also, as one might expect, when the temp-sensor is clamped to the chamber, the temperature varies less, & when it's detached from the chamber, the temperature varies more. See compare_temperature_air_1day.pdf & compare_temperature_chamber_1day.pdf.

New temp-sensor power supply vs old temp-sensor power supply

The new temp-sensor is less noisy and seems to work OK. It's not completely consistent with PSL-FSS_RMTEMP, but neither was the old temp-sensor. And even the air just outside the chamber isn't the same temperature as the chamber. So, the channels shouldn't line up perfectly anyways.

I unplugged the 'old' temp-sensor power supply for a few hours and plugged in the 'new' one, which doesn't have a box but has some capacitors and and 2 more voltage regulators. The MC1_TEMPS channel became less noisy. See noisetime.png & noisefreq.pdf. For that time, the minute trend shows that with the old temp-sensor power supply the temp sensor varies +/-30cts and with the new power supply, it is more like +/-5cts (and Volt/16,384cts * 1degF/10mV --> apprx +/-0.03degF). So, it's less noisy.

I kept the new temp-sensor power supply plugged in for about 8 hours, checking if new temp sensor power supply worked ok. Compared it with PSL-FSS_RMTEMP after applying an approximate calibration equation. See ver2_mc1_rmtemp_8hr_appxcal.png.

Just for kicks

Measuring time constant of temp sensor when detached from chamber. At 918858981, I heated up the temp sensor on of the mc1-mc3 chamber with my hand. Took hand off sensor at 918859253 and let it cool down to the room temperature. See temperature_sensor_tau.pdf.

Attachment 1: compare_temperature_channels.png

Attachment 2: compare_temperature_channels_zoom1.pdf

Attachment 3: compare_temperature_channels_zoom2.pdf

Attachment 4: compare_temperature_channels_zoom4.pdf

Attachment 5: compare_temperature_chamber_air.png

Attachment 6: compare_temperature_air2chamber.pdf

Attachment 7: compare_temperature_air_1day.pdf

Attachment 8: compare_temperature_chamber_1day.pdf

Attachment 9: noisetime.pdf

Attachment 10: noisefreq.pdf

Attachment 11: ver2_mc1_rmtemp_8hr_appxcal.pdf

Attachment 12: temperature_sensor_tau.pdf

1332

Mon Feb 23 11:07:01 2009

Kiwamu receives safety training

Bureaucracy

SAFETY

Osamu and Kiwamu received 40m safety training on Thursday, Feb 19, 2009

Kiwamu needs Osamu's close supervision at PSL enclosure and AP table

I hope they already read, understood and signed the laser SOP

1333

Mon Feb 23 16:42:08 2009

I've setup the GC650 camera (ID 32223) to look at the mode cleaner transmission. I've also added an alias to the camera server and client for this camera.

To use, type: "pserv1 &"on the machine you want to run the server on and "pcam1 &" on the machine you want to actually view the video. At the moment, this only works for the 64-bit Centos 5 machines, Rosalba, Allegra and Ottavia.

Note, you will generally want to start the client first (pcam1 or pcam2) to see if a server is already running somewhere. The server will complain that it can't connect to a camera if it already is in use.

I've setup the GC750 camera (ID 44026) to look at the the right most analog quad TV. This can be run by using "pserv2 &" and "pcam2 &".

If the image stops playing you can try starting and stoping the server to see if will start back up.

You can also try increasing or decreasing the exposure, to see if that helps. The increase and decrease buttons change the exposure by a factor of 2 for each press.

Lastly, the button "Read Epic Channel" reads in the current value from the channel: "C1:PEM-stacis_EEEX_geo" and uses it as the exposure value, in microseconds (in principle 10 to 1000000 should work).

For example, to exposre for 10000 microseconds, use "ezcawrite C1:PEM-stacis_EEEX_geo 10000" and press the "Read Epic Channel" button.

1334

Tue Feb 24 02:23:40 2009

Locking - MC board bad

Rob, Yoichi, Alberto, Kiwamu, Kakeru

We found that the OMC alignment feedback was on for the POS X loop even though the OMC was not locked.
This caused the PZT mirror to be tilted in yaw a lot. This was probably the reason for the mysterious shift in the AS beam last week, because the AS RF beam is picked up after this PZT mirror.
Rob aligned the OMC and we re-centered the AS PDs and the CCD.
This changed the DARM RF gain, so we changed it from 3 to 1. This gain used to be -1. It is still not understood why the polarity was changed.
The MC length was changed ? We should check the sideband transmission.

After this, we reached to the arm power 4. But the IFO loses lock immediately after the moving zero is turned off.
At this stage, the CARM loop bandwidth is supposed to be high enough that the moving zero is no longer necessary.
However, when we measured the MCL loop gain with several different AO path gains, the loop shape did not change at all.
This led us to suspect the AO path may not be connected. The cabling from the common mode board to the MC board seemed ok.
We tested the signal flow in the MC board using a signal generator and an oscilloscope.
Then we found that a signal injected to the IN2 (AO path) does not reach to the TP1A (right after the boost stages), though the signal is visible in the OUT2 (monitor BNC right after the initial amplifier (B-amp) for the AO path). The signal from IN1 (MC REFL) can be observed at TP1A. This means something is broken between the B-amp and the sum-amp in the AO path.
We will check the MC board tomorrow.

1335

Tue Feb 24 18:42:15 2009

Peter, Yoichi
Last night:

Quote:

However, when we measured the MCL loop gain with several different AO path gains, the loop shape did not change at all. This led us to suspect the AO path may not be connected. The cabling from the common mode board to the MC board seemed ok. We tested the signal flow in the MC board using a signal generator and an oscilloscope. Then we found that a signal injected to the IN2 (AO path) does not reach to the TP1A (right after the boost stages), though the signal is visible in the OUT2 (monitor BNC right after the initial amplifier (B-amp) for the AO path). The signal from IN1 (MC REFL) can be observed at TP1A. This means something is broken between the B-amp and the sum-amp in the AO path. We will check the MC board tomorrow.

Today we examined the MC board. With the extension board in place everything seemed fine. Without the extension board we could replicate the problem. Jiggling the IN2 jack caused the injected signal observed at TP1A to come and go. These jacks are unfortunately mounted directly on the board. We traced the problem to a resistor in this path (R30) which looked fishy. We soldered on a new 2K resistor with OWC and it fixed the problem.

1336

Wed Feb 25 03:10:24 2009

Rob, Yoichi, Kakeru, Kiwamu

Tonight, CARM -> MCL hand off was not stable. The MCF signal monotonically went up to +2V after CARM and MCL gain was turned down to zero.
This was repeatable and it only goes up (not down).
After a while, we found that putting sleep (~5sec) between the zeroing of CARM gain and MCL gain prevents this problem.

Handing off of CARM error signal from TR to PODC was also not robust.
It seems that the suitable gain changes every time.

tdsavg started to exit with errors. We rebooted fb40m.
When tdsavg returns an error, the cm_step script tries to write NaN into SPOB DC offset.
To prevent this, I put the tdsavg in a while loop which runs until tdsavg returns something other than NaN.

I was able to hand off to PODC several times, but could not proceed further because the IFO lost lock soon.

1337

Wed Feb 25 11:48:02 2009

Jenne

Wiener filtering update - work on filtering some S5 DARM_CTRL data

PEM

Quick update on my wiener filtering status:

Joe has been helping me get on the GRID, so I now have a grid certificate, and accounts on most/all of the clusters.

Joe also helped me get menkar to get S5 data so that I can do wiener filtering to the back-data.

I've been running the wiener filtering algorithm, and right now, it doesn't do anything to improve the DARM_CTRL data. I am confident that this is because something is funky in the wiener filtering algorithm somewhere. The indicator of this is that the wiener filtering calculation takes the same amount of time (~95 seconds) to calculate a filter for 64 seconds of data as for 1 hour of data (both for N = 2000 taps).

For reference, attached are my plots for the wiener filtering result for (1) 64 seconds of S5 data, and for (2) 3600 seconds of S5 data.

These plots were made using H1:DARM_CTRL as the signal to minimize, with 4 seismometers as the witness channels (EX_SEISX, EY_SEISY, LVEA_SEISX, LVEA_SEISY)

I'm working on figuring out what's going on with the filtering algorithm, and why it does work for C1:MC_L minimization, but does not work for H1:DARM_CTRL minimization.

Attachment 1: h1_DARM_64s_4seis_25Feb09.png

Attachment 2: h1_DARM_3600s_4seis_25Feb09.png

1338

Thu Feb 26 00:36:53 2009

Summary

C1:LSC-TRX_OUT broken (and fixed later).

Today, Kakeru tried to convert C1:LSC-TRX_OUT and C1:LSC-TRY_OUT to DAQ channels.
He edited C1LSC.ini in the chans/daq directory to add the channel but it did not work.
Then he reverted the file back to the original one.
But after we still could not access these channels from dataviewer nor tds tools.
We restarted daqd and tpman on fb40m, but the problem persisted. Even rebooting the whole fb40m did not help.
After inspecting the log file of daqd, it was clear that tpman was failing to create test points for those channels.
I rebooted c1daqawg and then restarted tpman and daqd on fb40m again.
This time, the problem went away.

1339

Thu Feb 26 01:24:44 2009

Martian wireless is back

Today, a new wireless router arrived.
I configured and installed it. Now the martian wireless network is back.
I updated the wiki page about the wireless network.
http://lhocds.ligo-wa.caltech.edu:8000/40m/Network

1340

Thu Feb 26 19:20:08 2009

ETMX camera centered. POX, POY PDs centered

General

Alberto, Yoichi

We centered the ETMX camera.
Alberto centered the POX and POY PDs.
We also updated the offset values of PD3 and PD4.

1341

Thu Feb 26 19:59:23 2009

Osamu, Yoichi

We tried locking today from about 2PM.
It took about 1000sec on average to acquire the initial lock.
After the initial lock is achieved, the hand-off/ramp-up steps were reasonably robust, although the AS beam sometimes fluctuates a lot (not good for mental health).

Like last night, the IFO loses lock at around arm-power=8.
We measured the CARM AO path loop gain at arm-power=4. We used the SR785 connected to the A-excitation channel of the common mode board through my TFSR785.py script.

The first attachment is the transfer function measured right after the arm power was ramped up to 4.
The overall bandwidth of the CM servo is only 400Hz. Note that since this is the loop gain of only the AO path, the low frequency gain is eaten by the MCL path.
The second attachment is the same transfer function measured after the AO path gain was increased by 6dB.
It is evident that the AO path is working.
We increased both the AO path and MCL gain by 18dB. The third attachment is the AO path TF in this state.
We then increased the arm power but lost lock at arm-power=6. We should have checked the DARM loop too.
BTW, these plots are automatically generated when you use TFSR785.py for transfer function measurements.

I added -notickle option to c1_watch_dr_bang, since tickling seems to be not necessary during the daytime (actually the initial lock was easier with no tickling).

As the construction work in the next building is now calmed down, I think it is ok to do locking during the day time, though I still plan to come at night.
The improvement of my brain efficiency during the day time may compensate for the longer wait time for initial lock.

Attachment 1: CM1.png

Attachment 2: CM2.png

Attachment 3: CM3.png

1342

Thu Feb 26 20:09:32 2009

HowTo

SR785 python scripts now produce plots

I updated the python scripts to remotely perform measurements with an SR785.
Now these scripts can plot the results immediately using python's matplotlib capability. The sample plots can be seen in my previous elog entry.
In addition to the transfer function (TFSR785.py) and spectrum measurement (SPSR785.py) scripts, I also wrote a script for time series measurements (TSSR785.py).
This is useful when you want to check the signal level flowing in the channels before determining the excitation amplitude.
TSSR785.py will measure and show the time series and histogram of the signal measured by the SR785.
More detailed usage is explained in this wiki page:
http://lhocds.ligo-wa.caltech.edu:8000/40m/netgpib_package

1343

Fri Feb 27 13:49:19 2009

Could not get past arm power of ~11 or so. I was suspicious of the transmon high-gain/low-gain PD handover, so I ran the matchTransMon scripts, but that did not help. I also removed the line in the cm_step script that increased the CM gain by 18dB at an arm power of 4. The gain of the CM servo will increase naturally as the power in the IFO builds up, so it may not be good to crank it right away. I tried several other CM gains, and watched the DARM loop, but still could not get past an arm power of ~10-11. I'm not sure what's wrong, but it may be that mysterious CM-servo/McWFS conspiracy, so we can try turning down the McWFS gain next time.

1344

Mon Mar 2 03:57:44 2009

Tonight's locking started with a boot fest of the FE computers which were all red when I came in.
It also took me sometime to realize that C1:IOO-MC_F was returning always zero to tdsavg, causing the offloadMCF script to do nothing.
I fixed this by rebooting c1iovme and c1iool0.

Like Rob on the thursday night, I was only able to reach arm power around 10.
This time, I turned down the MC WFS gain to 0.02 (from 0.3).
I also checked gains of most of the loops (MICH, PRC, SRC, DARM, CARM-MCL, CARM-AO).
All the loops looked fine until the lock was lost suddenly. Also the spectrum of MC_F did not change as the arm power was ramped up.
Actually, I was able to reach arm power=10 only once because I spent a long time checking the loop gains and spectrum at fine steps of the arm power.
So it is quite possible that this loss of lock was just caused by a seismic kick.

1345

Mon Mar 2 16:27:40 2009

Alberto

MC Drum Mode SR560 Preamplifier Replaced

Electronics

Today I checked out the SR560 around the lab. I confirmed that the one with the label "channel A noisy" is effectively mulfuctioning.

It was coonected to the lock-in amplifier set up for the drum mode peak readout.

I repleaced that with a working one.

1346

Mon Mar 2 21:16:32 2009

Low-gain High-gain PD switching may not be working well

Osamu, Yoichi

This afternoon, I run the locking script while doing calculations for the upgrade.
The IFO lost lock even at lower arm powers (around 6) if it was operated for a while (~ 5min).
It seemed as if there were some intermittent glitches (seismic? laser?) causing the lock losses.
We also saw once the TRX and TRY signals saturated at around arm power = 11 when there was a large fluctuation in the arm power.
Osamu suggested that it looked like the high-gain to low-gain PD switching was not working.

I won't come tonight as I may have caught a cold, but if someone comes tonight, it is worth checking the PD switching.

1347

Tue Mar 3 08:44:31 2009

air cond. maintenance today

PEM

IFO room 104 air conditions will be shut down for maintenance today.

This should be finished by noon.

The temperature and particle count variation can be more than usual.

1348

Tue Mar 3 10:39:07 2009

Alberto

c1lsc discontinued functioning

LSC

The c1lsc has been unstable since last night. Its status on the DAQ screen was oscillating from green to red every minute.

Yesterday, I power recycled it. That brought it back but the MC got unclocked and the autolocker could not get engaged. I think it's because the power recycling also turned c1iscaux2 off which occupies the same rack crate.

Killing the autolocker on op340 e restarting didn't work. So I rebooted also c1dcuepis and burt-restored almost all snapshot files. To do that, as usual, I had to edit the snapshot files of c1dcuepics to move the quotes from the last line.

After that I restarted the autolocker that time it worked.

This morning c1lsc was again in the same unstable status as yesterday. This time I just reset it (no power recycling) and then I restarted it. It worked and now everything seems to be fine.

1349

Tue Mar 3 11:39:50 2009

Kiwamu and I brought 2 SUPER MICRO PCs from Willson house into 40m.

Both PCs are hooked up into Martian network. One is named as bscteststand for BSC which has been set up by Cds people and another one is named kami1 for temporary use for CLIO which is a bland new, no operating installed PC. This bland new PC will be returned Cds or 40m once another new PC which we will order within several days arrives.

IP address for each machine is 131.215.113.83 and 131.215.113.84 respectively.

We have installed CentOS5.2 into the new PC.

1350

Tue Mar 3 19:26:44 2009

Low-gain High-gain PD switching may not be working well

I checked the switching of the QPDX from high gain to low gain.
Switching happens as expected, but the low gain QPDX output was very low compared to QPDY.
Also the digital gain for the high gain TRX was not matched with the low gain one. So when the switching happens, there is a large jump in the TRX.

I also found that the offset values for the low gain QPDX were totally wrong. I adjusted it.
Then I removed a beam splitter in front of the QPDX to increase the power falling on it.
But still the low gain QPDX output is four times lower than the low gain QPDY.

I'm still working on it. So don't expect the switching to work correctly at this moment.
I'm planning to be back after the dinner.

Quote:

1351

Tue Mar 3 23:59:26 2009

Low-gain High-gain PD switching may not be working well

Quote:

This sounds like the QPD whitening gain sliders may be stuck. The slider twiddling script should be run, or the sliders should be twiddled by hand.

1352

Wed Mar 4 03:37:51 2009

Low-gain High-gain PD switching may not be working well

Quote:

This sounds like the QPD whitening gain sliders may be stuck. The slider twiddling script should be run, or the sliders should be twiddled by hand.

Yes, it was indeed the whitening gain slider problem.
I moved them and the QPDX gain went up suddenly. I reinstalled the BS in front of the QPDX and adjusted the offsets, gains accordingly.
Now the high-gain to low-gain switching is fine.

1353

Wed Mar 4 03:50:17 2009

Still won't go above arm power 10

Yoichi, Kentaro

The IFO still loses lock at around arm power 10.
I attached time series of various error signals when losing lock.
In all of the three cases, both of the arm powers go up rapidly just before losing lock.
(The first attachment was taken before I fixed the QPDX switching, so you can see saturation in TRX.)
But PD1_DC (the DC power in the PRC) did not go up in the third case.

I should also check correlations with laser power, CARM length (OSEM signals), seismic noise etc.

Attachment 1: lockLoss1.png

Attachment 2: lockLoss2.png

Attachment 3: lockLoss3.png

1354

Wed Mar 4 12:38:07 2009

Alberto

Computer Scripts / Programs

3f locking simulations

I simulated the REFL signals demodulated at the differential frequencies of the sidebands (f2-f1), at their summed frequencies (f2+f1). I also simulated their combination as in the Double Demodulation.

I repeated the simulation for:

- Old (current) 40m

- 40m Upgrade

- AdvLIGO

I'm attaching the results to this elog entry.

The plots show how the signal varies exploring the two-dimensional space of the demodulation frequencies (differential and sum).

Both the Upgrade and the Old40m's signals look anomalous since the zero-crossing point does not change with the demodulation phases.

I suspect there's is a problem with the optickle model of the 40m.

Attachment 1: 23_3f_40mOld_DDplots.pdf

Attachment 2: 59_3f40m_Upgrade_DDplots.pdf

Attachment 3: 20_3f_AdvL_DDplots.pdf

1355

Wed Mar 4 17:20:04 2009

I've updated the digital camera python code as well as changed the network topology.

At the moment, both cameras are connected to a small gigabit switch which only talks to Ottavia. This means all camera servers must be run on Ottavia, allow camera output is still UDP multicast so any machine capable of running gstreamer can pick up the images.

The server and client programs now have the ability to read a configuration file for the setup of the cameras. They default to pcameraSettings.ini, but this can default can be changed with a -c or --config option

For example, "serverV3.py --config pcam1.ini" will run the server using the pcam1.ini settings file. Similarly, "client.py --config pcam1.ini" will also take the IP settings from the config file so that it knows at which port and IP to listen.

These programs and .ini files have been placed in /cvs/cds/caltech/apps/linux64/python/pcamera/

I've updated the cshrc.40m aliases so that it uses the new configuration file options, so now pcam1 calls "client.py -c pcam1.ini" in the above directory.

So to start a client use pcam1 or pcam2 (for the 32223 camera in PSL looking at MC trans or 44026 looking at an analog moniter in the control room respectively). These can be run on Allegra, Rosalba or Ottavia at the moment.

To start a server, use pserv1 or pserv2. These *must* be run on Ottavia.

I've also added a -n or --no-gui option at Yoichi's request, one which just starts up and plays, with no graphical gui.

Lastly, I've made some changes to the base pcamerasrc.py file, which should make display more robust. After a failed transmission of an image from the camera to Ottavia, it should re-attempt up to 10 times before giving up. I'm hoping this will make it more robust against packet loss. The change in network topology has also helped this, allowing 640x480 to be transmitted on both cameras before tens of minutes before a packet loss causes a stop.

1356

Wed Mar 4 17:59:14 2009

ezca tools and tds tools work around

Some of ezca commands and tds commands sporadically fail with a segmentation fault on linux machines.
As far as I know, ezcawrite, ezcastep, ezcaswitch, and tdswrite have this problem.
These are commands to write values into epics channels. So usually people do not check the exit status of those commands in their scripts.
This could cause incomplete execution of, for example, down scripts.
Ideally, this problem should be fixed in the source codes of the problematic commands.
However, I don't have a patience to wait it to happen, and I needed to fix these problems immediately for the lock acquisition.
So I resorted to a hacky solution.
I renamed those commands to *.bin, e.g. ezcawrite -> ezcawrite.bin.
Then wrote wrapper scripts to repeatedly call those commands until it succeeds.
For example, ezcawrite now looks like,

#!/bin/csh -f
setenv POSIXLY_CORRECT
while (! { ezcawrite.bin $* })
      echo "Retry $0 $*"
end

So, when ezcawrite.bin fails, the command retries it and show a message "Retry ....".

If you need to call the original commands, you can always do so by adding ".bin" at the end of the command name.
Currently the following commands are wrapped.
ezcawrite, ezcaservo, ezcastep, ezcaswitch, tdswrite, tdssine.

Please let me know if you have any trouble with this.

1357

Wed Mar 4 23:42:45 2009

I made the following change to correct the sign of the 126MON channel:

allegra:c1aux>ezcawrite C1:PSL-126MOPA_126MON.EGUF -410
C1:PSL-126MOPA_126MON.EGUF = -410
allegra:c1aux>ezcawrite C1:PSL-126MOPA_126MON.EGUL 410
C1:PSL-126MOPA_126MON.EGUL = 410
allegra:c1aux>

1358

Thu Mar 5 00:06:32 2009

We found that the MC REFL image was no longer round and that the MCWFS DC quadrant spots were mostly
in one quadrant. So we re-centered the MCWFS beams in the following way:

1) We unlocked the MZ and adjusted the PZT voltage to keep the beam on the WFS from saturating.
2) Re-aligned the black hole beam dump to center its beam in its aperture.
3) centered the beam on the MCWFS optics and MCWFS QPD displays.
4) Relocked MC.

Below is the image of the IOO Strip tool. You can see that the MC REFL DC is now more flat. The
MC pointing has also been changed (see the MC TRANS HOR & VERT channels). The MC transmitted
light is also now more stable and higher.

We tried to center the QPD, and we found that there were a few hundred mV of dark offset for each 
quadrant of QPD. We adjusted them with this scripts:
/cvs/cds/caltech/scripts/MC/WFS/McWFS_dc_offsets

Attachment 1: IOO_graph.jpg

1359

Thu Mar 5 01:09:29 2009

We tried to run DMF on mafalda, but it didn't work. I tried to compile it using Rob's elog instructions.
On mafalda, I started matlab and ran the mdv_config.m to set up mDV. I tested that the seisBLRMS.m
script ran and correctly produced changes in the seisBLRMS strip tool. but when I tried to compile it I got:

>> mcc -v -m -R -nojvm seisBLRMS.m
Warning: Duplicate directory name: /cvs/cds/caltech/apps/linux/matlab/toolbox/local.
Compiler version: 4.6 (R2007a)
Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/matlab/mcc.enc
Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/signal/mcc.enc
Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/control/mcc.enc
Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/filterdesign/mcc.enc
Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/shared/controllib/mcc.enc
Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/ident/mcc.enc
Warning: an error occurred while parsing class FilterDesignDialog.AbstractEditor:
Undefined function or variable 'DAStudio.Object'.

> In /cvs/cds/caltech/apps/linux/matlab/toolbox/shared/filterdesignlib/@FilterDesignDialog/@CoeffEditor/schema.p>schema at 9
Warning: an error occurred while parsing class FilterDesignDialog.CoeffEditor:
Invalid superclass handle.

Processing /cvs/cds/caltech/apps/linux/matlab/toolbox/fixedpoint/mcc.enc
terminate called after throwing an instance of 'ApplicationRedefinedException*'
Abort (core dumped)
"/cvs/cds/caltech/apps/linux/matlab/bin/mcc" -E "/tmp/fileRnU5Qj_31324": Aborted
??? Error executing mcc, return status = 134.

In the meantime, I've started up a green terminal on allegra which is ssh'd into megatron.
On megatron there is a regular matlab session which is running seisBLRMS.m as a matlab script
and the seis DMF channels are getting updated.

1360

Thu Mar 5 02:24:19 2009

I added the following repos which I found on allegra to megatron and then did a 'yum install sshfs' on both machines:

allegra:yum.repos.d>l total 28 -rw-r--r-- 1 root root 428 Feb 12 16:47 rpmforge.repo -rw-r--r-- 1 root root 684 Feb 12 16:47 mirrors-rpmforge -rw-r--r-- 1 root root 1054 Feb 12 16:47 epel-testing.repo -rw-r--r-- 1 root root 954 Feb 12 16:47 epel.repo -rw-r--r-- 1 root root 626 Feb 12 16:47 CentOS-Media.repo -rw-r--r-- 1 root root 1869 Feb 12 16:47 CentOS-Base.repo -rw-r--r-- 1 root root 179 Feb 12 16:47 adobe-linux-i386.repo

This also required me to import the rpmforge GPG key:

sudo rpm --import http://dag.wieers.com/rpm/packages/RPM-GPG-KEY.dag.txt

1361

Thu Mar 5 05:07:09 2009

Wednesday night locking

Tonight, I was having a problem with the PO_DC hand-off.
It fails most of the time.
I increased the averaging time for the PD1_DC offset measurement.
I also wrote a script to match the gain of the transmission DC and the PO_DC signals.
This script (/cvs/cds/caltech/scripts/CM/matchPODCGain ) measures the gains of the old (TRX+TRY) and new (PO_DC) signals at 150Hz and returns the optimal value to be put into the input matrix.
cm_step script calls matchPODCGain to determine the matrix element value for the PO_DC signal.

Even with this script, the hand-off was still unreliable.
I checked the AO path loop gain just before the hand off. It looked normal.
Then I realized that the oscilloscope I hooked up to the PO_DC signal using a T-BNC may be introducing some noise into the channel.
So I removed it. Then the PO_DC hand off went well at least once.
The IFO still loses lock at around arm power 10.

I attached time series of the latest lock loss. The second attachment is a zoom of the first one.
This time, there is a glitch in the ETM feedback signals, which is also present in the DARM and CARM and error signals.
I saw this kind of glitches several times today.

Attachment 1: lockLoss5.png

Attachment 2: lockLoss5-zoom.png

1362

Thu Mar 5 23:18:38 2009

I found that tdsdata doesn't work.

When I star tdsdata, he takes a few ~ 10 seconds of data, and he dies with a message "Segmentation fault".
I tried to get data for some times and some channels, and this problem was observed everytime.
I also tried tdsdata on allegra, op440m and mafalda, and it didn't work on all of them.

Yesterday, I got a new version of tdsdata (which modified the problem of Message ID: 1328) and tried to build 
thme on my directory (/cvs/cds/caltech/users/kakeru.....)
This may have some relation to this problem.

1363

Fri Mar 6 01:04:49 2009

Kiwamu IZUMI

!! lock-in amp disconnected !!

IOO

The power supply of a lock-in amp, which is on the Y-arm side of PSL clean room, was pulled out by my mistake.

Then I reconnected it, but I don't know whether it is re-adjusted properly.

I'm sorry about this. If you are using that amp, it should be checked.

1364

Fri Mar 6 05:44:14 2009