Koji had the good idea of trying to measure the motion of the POP beam, and feeding that signal to PRM yaw to stabilize the motion.  To facilitate this, I have installed a 50% beam splitter before the POP 110/22 PD (so also before the camera). 

Before touching anything, I locked the PRM-ITMY half-cavity so that I had a constant beam at POP.  I measured the POP DC OUT to be 58.16 counts.  I then installed a 1" 50% BS, making sure (using the 'move card in front of optic while watching camera' technique) that I was not close to clipping on the new BS.  I then remeasured POP DC OUT, and found it to be 30.63.  I closed the PSL shutter to get the dark value, which was -0.30 .  This means that I now have a factor of 0.53 less light on the POP110/22 PD.  To compensate for this, I changed the values of the power normalization matrix from 0.01 (MICH) to 0.0189, and 100 (PRCL) to 189.

After doing this, I restored the ITMX and am able to get several tens of seconds of PRMI lock (using AS55Q and REFL33I). 

I found several QPDs in the PD cabinet down the Y arm, but no readout electronics.  The QPD I found is D990272.  I don't really want to spend any significant amount of time hacking something for this together, if Valera can provide a QPD with BNC outputs. For now, I have not installed any DC PD or razor blade (which can be a temporary proxy for a QPD, enough to get us yaw information).

Something that I want to look at is the coherence between seismic motion and PRM motion.  Since Den has been working on the fancy new seismometer installations, I got caught up for the day with getting the new corner seismometer station set up with a T240.  Later, Rana pointed out that we already have a Guralp sitting underneath the POX table, and that will give us a good first look at the coherence.  However, I'm still going to write down all the cable thoughts that I had today:

The cables that came with the electronics that we have (from Vladimir and tilt meter -land) are not long enough to go from the seismometer to 1X7, which is where I'd like to put the readout box (since the acquisition electronics are in that rack). I want to make a long cable that is 19pin MilSpec on one end, and 25pin Dsub on the other.  This will eliminate the creative connector type changes that happen in the existing setup.  However, before making the cable, I had to figure out what pins go to what.  So.

25pin Dsub          19pin MilSpec

1                   P

2                   N

3                   E

4                   No conn

5                   D

6                   R and V

7                   H

8                   J

9                   No connection

10                  T

11                  F

12                  L

13                  No conn

14                  B

15                  A

16                  R and V

17                  No conn

18                  C

19                  G

20                  G

21                  K

22                  U

23                  No conn

24                  S

25                  M 

I am not sure why R and V are shorted to each other, but this connection is happening on the little PCB MilSpec->ribbon changer, right at the MilSpec side.  I need to glance at the manual to see if these are both ground (or something similar), or if these pins should be separate. Also, I'm not sure why 19 and 20 are shorted together.  I can't find (yet) where the short is happening. This is also something that I want to check before making the cable.

Den had one Female 19 pin MilSpec connector, meant for connecting to a T240, but the cable strain relief pieces of the connector have 'walked off'.  I can't find them, and after a solid search of the control room, the electronics bench, and the place inside where all of Den's connectors were stored, I gave up and ordered 2 more.  If we do find the missing bits for this connector, we can use it for the 2nd T240 setup, since we'll need 2 of these per seismometer. If anyone sees mysterious camo-green metal pieces that could go with a MilSpec connector, please let me know.

Since I keep asking Manasa to "measure" distances off of the CAD drawing for me, I thought I might just write them all down, and quit asking.

So, these are only valid until our next vent, but they're what we have right now.  All distances are in meters, angles in degrees.

[Annalisa, Manasa]

More optics have been put on the table. Direction of the rejected beam from the 532nm faraday estimated to be ~1.7 deg along -y axis.

Transmon QPD, TRY and camera have beams on them for locking Y arm. Oplev configuration is waiting for it's lens to arrive.

I rotated some mounts along the green beam path, and I started aligning the beam again.

The beam is aligned up to the waveplate just before the doubler crystal, even if I couldn't reach more than 88% transmission for the Faraday. Next week I will finish the alignment and I'll put the lenses that Manasa already ordered.

Ah, AWESOME. Indefinite PRMI lock was finally achieved.

POP setup

- Looked at the POP setup. Checked the spot on POP110 PD. Found some misalignment of the beam.
  The beam spot was aligned to the PD with PRMI locked. The value of POP110I almost doubled by the alignment
  and recovered previous value of 400. Therefore previous normalization values of MICH 0.01 / PRCL 100 were restored.

- Placed PDA36A (Si 3.6mmx3.6mm) on the POP path that Jenne prepared. The gain knob was set to 40dB.
  Since the original spot had been too small, a lens with f=50mm was inserted in order to expand the beam.
  Connected the PD output to the SMA feedthrough on the ITMX table enclosure.
  I found the BNC cable labeled "PO DC" hanging. Connected this cable to the enclosure SMA.

- Went to the LSC rack. Found the corresponding PO DC cable. Stole the POPDC channel from POP110I Bias T to this PO DC cable.

- Razor blade setup: Machined a junk Al bracket in order to fix a razor blade on it. Attached the Al bracket to a sliding stage.

Locking

- Locked the PRMI with REFL33I&AS55Q. Cut the beam into half by the razor blade.

- Made a temporary PRM_ASC_YAW filter.
  Zero: 0Hz Pole: 2kHz
  Resonant Gain 3.2Hz Q:2 Height 30dB
  Butterworth 2nd-order 60Hz

  => Expected UGF 0.1Hz&10Hz

- CDS: By the work described in this entry, the POPDC signal was connected to the "MC" bank of the LSC.
            BTW, the 11th row of the LSC output matrix is connected to the PRM_ASC_YAW.

- The "MC" servo input (i.e. the POPDC signal) was normalized by POP110I (without SQRTing).

- Engaged the PRM ASC path. Gradually increased the gain of PRM_ASC_YAW. G=+100 seemed to be the best so far.
  It was visible that the spot on the POP CCD was stablized in yaw.

- The lock lasted for ~40min. Took several measurements, alignment adjustment, etc.

- Tweaking the PRM ASC unlocked the PRMI.

- Locked again. Switched from REFL33I/AS55Q (x1/x1) combination to REFL55I/REFL55Q (x1/x0.3) combination.
  This also kept the lock more than 20min.

I have done a quicky offline Wiener filter to check how much PRM yaw motion we can subtract using a seismometer in the corner station.  This work may be redundant since Koji got the POP beam shadow sensor feedback loop working on Friday night.

Anyhow, for now, I used the GUR2 channels, since GUR2 was underneath the ITMX chamber (at the north edge of the POX table).  Note that Zach is currently borrowing this seismometer for the week.

I used GUR2_X, GUR2_Y and GUR2_Z to subtract from the PRM_SUSYAW_IN1 channel (the filename of the figure says "GUR1", but that's not true - GUR1 is at the Yend).  All 4 of these channels had been saved at 2kHz, but I downsampled to 256 (I probably should downsample to something lower, like 64, but haven't yet).  There is no pre-filtering or pre-weighting of the data, and no lowpass filters applied at the end, so I haven't done anything to remove the injected noise at higher freqs, which we obviously need to do if we are going to implement this online.

If I compare this to Koji's work (elog 8562), at 3.2Hz, he gets a reduction of 2.5x, while this gets 10x.  At all other frequencies, Koji's work beats this, and Koji's method gets reduction from ~0.03Hz - 10Hz, while this is only getting reduction between 0.4Hz and 5Hz.  Also, this does not include actuator noise, so the actual online subtraction may not be quite as perfect as this figure.

I want to redo this estimate of where RIN comes from, since Den did this measurement before I put the lens in front of the POP PD. 

While thinking about his method of estimating the PR3 effect, I realized that we have measured numbers for the pendulum frequencies of the recycling cavity tip tilt suspensions. 

I have been secreting this data away for years.  My bad.  The relevant numbers for Tip Tilts #2 and #3 were posted in elog 3425, and for #4 in elog 3303.  However, the data for #s 1 and 5 were apparently never posted.  In elog 3447, I didn't put in numbers, but rather said that the data was taken.

Anyhow, attached is the data that was taken back in 2010.  Look to elog 7601 for which TT is installed where. 

Conclusion for the estimate of TT motion to RIN - the POS pendulum frequency is ~1.75Hz for the tip tilts, with a Q of ~2.

Yend table - Current status

OPLEV

Today the 2m focal length lens along the oplev path (just after the laser) has been added. In Manasa's layout it allows to have a beam waist of 3.8mm on the OPLEV QPD, even if it seems to be smaller.

The laser is closer to the box wall than the layout shows (it's on the line n.1 instead of line n.9), so maybe it has to be moved in the position shown in the layout, as Steve suggests, to leave empty space just before the window.

Rana suggests a 2mm diameter beam on the QPD, so a new calculation has to be done to add a second lens.

GREEN

The beam has been aligned until the doubler, but after the crystal it it has a small tilt, so a better alignment has to be done.

Moreover, the beam waist has to be measured after the Faraday for the green, in way to choose the focal length of the lenses necessary for the mode matching.

Then the three steering mirrors to send the beam into the arm have to be put.

TRANSMON PATH

A lens which has to be put on the Transmon path (already ordered) has to be added, and the beam alignment on the QPD-y and on the PDA520 has to be done.

[Evan, Jenne]

Evan brought the Guralp handheld readout paddle and cables back from the ATF (Zach is using GUR2 and one of the T240s for gyro stuff this week), and we recentered the GUR1 masses.  N/S and Vert were okay (within 0.1 V), but E/W was at -0.5 V, so we set it at zero.  We then plugged the Guralp back in, and turned on the readout box.

There isn't much of a change on the BLRMS on the wall, so it's possible that we weren't actually having any trouble anyway. 

Koji noticed that earlier this afternoon the Yarm ASS was working, but then after dinner it was no longer working.  I saw that the ETMY trans camera beam was clipped.  These things precipitated a visit to the Yend station. 

I saw that the beam on the optic that steers the camera beam to the camera was very, very low, almost falling off the optic.  The only mirror which steers to this optic is the harmonic separator which reflects the IR, and transmits the green.  I turned the pitch knobs on the harmonic separator until the beam was roughly centered on all 3 optics between the separator and the camera (BS to QPD, BS to TRYDC and Y1 for camera).  The yaw was fine, so I didn't touch it.

I then adjusted the steering mirror to the camera, and the BS pointing to the DC PD.  I have not touched the BS pointing to the QPD.  Once the beam was on the TRY PD, Koji ran the ASS script, and I recentered the beam on the DC PD.  During this time, Koji had the Yarm triggering using -1 in the POYDC element of the matrix.

The harmonic separator is not mounted in a nice way (I'm assuming that Annalisa is in the middle of things, and she'll get back to it after the green work), so the TRY PD and camera will need to be aligned again, so I didn't do any ASS-recentering-ASS iteration tonight.

The Yarm ASS works nicely again, getting TRY to ~0.89 . 

I locked the Xarm on green.  At the PSL table, I adjusted the steering mirror to get the beam centered on the GTRX DC PD.  We need a lens for this, and presumably for the GTRY as well. 

I then went down to the Xend, and adjusted the steering mirrors to maximize the transmitted green power.  I got as high as 2150 counts.

Either the alignment is particularly delicate, or something isn't quite right, but when I put the lid back on the optical table's box, the arm will no longer lock on the 00 mode.  It's pretty typical that the cavity will unlock while you put on the lid, but usually if you bang on the underside of the table, or toggle the green shutter, you'll get back to the 00 mode.  Tonight however, I can't get the 00 mode if the lid is on.  If I slide the lid off just enough to get my hand inside, then block the green beam with my hand, I immediately lock on the 00 mode.  Even if I gently slide the lid back on, I unlock the cavity, and with the lid on can't get better than a 01 mode in yaw.  I repeated this a few times, with the same result. 

A goal for the next few days:  Re-find the Xgreen beatnote.  Once we have the PRMI locking stably and reliably, we want to move on to PRFPMI.   

Note that I'm supposed to return one of the two green beat PDs and the power supply.
They are on the REFL path. I'll work on the restoration of the beat configuration.

 I'm planning to remove the ETMY optical table enclosure and move it over to CES Shop 8am Thursday morning.

We'll install spring loaded lathes, hooks and quick release pins.

The bridge will be reinforced with steel plate to support release pins on posts.

There will be an other cut out for cable feedtrough as it is shown on elog #8472

Let me know if this timing does not fit your work.

I have figured out all the issues, and successfully installed the new versions of the LAL software.  I am now going to get the summary pages set up using the new code.

GREEN

The new lenses arrived, and I put the right 250mm before the doubler. I'm still not so confident with the alignment, because I cannot get more than 11-12 uW out from the "green" Faraday, with more than 200uW going in.

TRANSMON

I replaced the Y1 mirror with an HR1064-HT532. The alignment has to be done. Today the 50cm focal length lens arrived, and I'm going to put in tomorrow.

I tested On-Track (from LLO) OT 301  amp with PSM2-10 qpd. It was responding. Jenne will calibrate it.  The 12V DC ps input is unipolar.

The one AC to DC adapter that Jenne tried was broken.

I noticed a couple potential issues in some of the models while I was investigating the ADC/DAC situation:

c1ioo links to ADC1, but there are broken links to the bus selector that is supposed to be pulling out channels to go into the PSL block.  They're pulling channels from ADC0, which it's not connected to, which means these connections are broken.  I don't know if this means the current situation is broken, or if the model was changed but not recompiled, or what.  But it needs to be fixed.

c1scy connects ADC_0_11, label "ALS_PZT", to an EpicsOutput called "ALS_LASER_TEMP", which means the exposed channel is called "C1:SCY-ALS_LASER_TEMP".  This is almost certainly not what we want.  I don't know why it was done this way, but it probably needs to be fixed.  If we need and EPICS record for this channel it should come from the ALS library part, so it gets the correct name and is available from both ends.

GREEN

I still have problems in maximizing the power out from the doubler. I realized that the real green power I obtain is about 30 uW, and it is the power which really enters the Faraday.

Before I was measuring it just after the Harmonic separator, and there was some residual IR beam which increased the power on the power meter, that's why I obtained about 200 uW.

I also tried to slightly vary the position of the mode matching lens, but I was not able to get more than 30 uW on the power meter.

TRANSMON PATH

The 50 cm focal length lens has been added in the position shown on Manasa's layout, and the beam has been focused on the PD.

I deleted a bunch of useless categories from the 40m elogd.cfg file. IF you find your category has been deleted, you can now learn how to categorize yourself into the existing categories. ELOG restarted and log file zeroed.

We talked about the thing that watches the scripts for autolocking during the meeting today.

I've resurrected the Perl-Tk GUI that we used through i/eLIGO for watching the IFO and running the appropriate scripts. This is not meant to be a replacement for aLIGO stuff, but just something to get us going for now. I expect that we will make some new fanciness which will eclipse this, but I brought it back so that we don't start off with some 'Advanced' system which is worse than the old one.

You can run it from scripts/c1/ by typing ./AutoRUN.pl. It pops up the GUI and starts in a Disabled mode where it watches and does nothing.

I have done some editing of the GUI's code so that it uses caget / caput instead of ezca binaries. New stuff is in the SVN.

Next up is to start testing it and fixing it up so that it uses the thresholds set in the LSC screens rather than some hardcoded values.

Eventually we should also convert all of its daughter scripts from tcsh to bash to keep Jamie's blood pressure in the low hundreds...

Kiwamu had an old set of scripts for measuring the sensing matrices, but they were hidden away in ..../scripts/general/kiwamuscripts/pyplant . I have moved them to a more useful place, and updated them.

The useful scripts (the main one is SensResp.py, and the PRMI-specific one, runPRMI_SENS.py, which calls SensResp.py) have been moved to .../scripts/LSC .  I have also created a folder within the LSC scripts folder called SensMatData for the data.

The 2 big changes to Kiwamu's scripts:  The ezca library that he was calling wasn't working.  I switched it over to using the one that Yuta wrote, in ..../scripts/pylibs.  Also, Kiwamu's script was written back during a time where we must have only had one total lockin for the whole LSC model.  Now we have one per PD in the input matrix.  This meant that several of his channel names were wrong.  I have fixed this, and also made it measure all the sensors at once using tdsread of the _OUT16 channels (the OUT16's have some AA action, other EPICS channels don't).

So, now (after you're locked), it shakes one "mirror" (the ITMs are shaken differentially at the same time, as one "mirror"), and reads out all of the RF PD lockin values.  Then it moves to the next mirror.  (For the PRMI case, there are only 2 "mirrors":  The ITM set and the PRM.)  All of the information is stored in a dictionary, which is written to a text file. 

The format of the dictionary is:

{ OPTIC_1: [Photodiode_1, Lockin_I, Lockin_Q], [Photodiode_2, Lockin_I, Lockin_Q], OPTIC_2: [Photodiode_1, Lockin_I, Lockin_Q], [Photodiode_2, Lockin_I, Lockin_Q] }

At this point, I am too tired to actually do a measurement, although next time the PRMI is locked, we should just have to run the runPRMI_SENS.py, and look at the data.  I'm also not quite sure how to extract the information from a dictionary after it has been written to a text file.  This may not be a good way to store data, and I'll ask Jamie about it tomorrow.

OTHER NOTES:

* I need to set up another iteration of the sensing matrix measurement with no drive, measuring several times, to get an estimate of the error in a single measurement.

* I had the PRMI locked on AS55Q/REFL33I for more than half an hour.  Then the MC started unlocking semi-regularly.  Seismic was good except for one EQ ~2 hours ago.  After the earthquake (unlocked MC, but no tripped optics), the MC has remained locked.

* The LSC Lockin Overview screen does not click-through to the _SIG individual screens.  We need to fix the path to these screens.

* All of the _SIG filters are band passes around 285 Hz, but the names of the filters all say 238Hz.  I need to fix all 27 of these.

* We can perhaps change the LSCoffsets script someday to use tdsread a few times, and average the results (since the PDs don't have lowpass filters, and we're measuring the offset of the IN1 location, not the OUT).  This way we can hopefully measure all the PDs at once and speed up the script, without having failed tdsavg runs.

All ETMY optical table electronics- lasers-pds turned off, disconnected in order to remove enclosure.

Koji locked the PRMI for me, and I took some data.  I haven't finished figuring out what to do with it / writing a processing script.

Here is the data, in a python dictionary (not for you to read, but so that it's here and you can use it later if you want).

{'AS55_Q': [['ErrorBarData0', '-1.60826e-05', '0.000154774'], ['ErrorBarData1', '-1.61949e-05', '-9.69142e-05'], ['ITMs', '-0.134432', '0.00240338'], ['PRM', '0.0525864', '0.145516']], 'REFL55_Q': [['ErrorBarData0', '-0.00088166', '-0.00294315'], ['ErrorBarData1', '0.00298076', '-0.000466507'], ['ITMs', '-0.573825', '-0.0865747'], ['PRM', '1.94537', '0.534968']], 'REFL33_Q': [['ErrorBarData0', '0.000868208', '0.000785702'], ['ErrorBarData1', '-0.00136268', '-0.000288528'], ['ITMs', '-0.0653009', '-0.0112035'], ['PRM', '0.875275', '0.419765']], 'REFL11_I': [['ErrorBarData0', '-0.147347', '0.136075'], ['ErrorBarData1', '0.351823', '0.160556'], ['ITMs', '-12.0739', '-80.1513'], ['PRM', '6991.11', '7073.74']], 'REFL33_I': [['ErrorBarData0', '-0.00100624', '0.00134366'], ['ErrorBarData1', '0.00373581', '0.000783243'], ['ITMs', '-0.399404', '-0.774793'], ['PRM', '67.4138', '68.8886']], 'REFL11_Q': [['ErrorBarData0', '-0.0173368', '0.0141987'], ['ErrorBarData1', '0.100048', '0.0882165'], ['ITMs', '6.46585', '-26.2841'], ['PRM', '1653.42', '1663.96']], 'AS55_I': [['ErrorBarData0', '-1.87626e-05', '2.24596e-05'], ['ErrorBarData1', '-5.46466e-05', '-2.96552e-07'], ['ITMs', '-0.00531763', '0.00130579'], ['PRM', '-0.100501', '-0.0706334']], 'REFL55_I': [['ErrorBarData0', '-0.000774208', '-5.32631e-05'], ['ErrorBarData1', '0.00347621', '0.0025103'], ['ITMs', '-0.115633', '-0.83847'], ['PRM', '72.8058', '74.2347']]}

The structure is that each sensor has some "error bar" measurements, when there was no drive to any optics (I, then Q of the lockin), and then response to different optics' drives (waiting 20sec after turning on the oscillator before making a measurement, since the lockin has 0.1Hz lowpasses.  ).

The amplitude that Kiwamu had of 4000 cts in the LSC lockin was fine for MICH, but made PRCL unlock, so this data was taken with an amplitude of 1000 counts, at a frequency 283.1030 Hz. 

Since this is only barely above the UGF for both MICH and PRCL loops, I also have OLTF information at 283Hz from DTT:  PRCL mag = -1.05264 dB, phase = 24.6933 deg, MICH mag = -8.50951 dB, phase = 31.3948 deg.

I have started writing a script SensMatAnalysis.py in the scripts/LSC directory to do the analysis, but after having talked to Koji, I need to do more thinking to make sure I know what I'm doing.  Stay tuned for actual analysis later.

[Rana, Annalisa] 

 GREEN

 The alignment for the green has been improved, so that we have much more green power.

The first lens position along the IR path has been changed in way to have the beam waist at the center of the first Faraday. In this way we had about 91% of the input power out from it.

The two cylindrical lenses which were used to correct the ellipticity of the beam have been replaced by a single lens. Its focal length is intermediate between the focal lengths of the two cylindrical. 

Moving the position of the lens before the doubler crystal and improving the alignment we got about 1mW of green light (0.35% of the incoming IR beam).

TO DO

After aligning the green beam through the second Faraday, the beam waist of the outgoing beam has to be measured and the mode matching calculation has to be done to choose the two MM lenses. Then the steering mirrors will be placed to send the beam into the arm.

 It  will arrive around 10 am Monday morning.

 TODO:

1. We need to replace all of the floppy anodized Al dumps with clean razor blade dumps on stiff mounts. BOTH of the rejected ports of the 1064 FI need some kind of custom dump.
2. All of the leakthrough beams of the HR mirrors also need razor dumps. A good rule of thumb is that your first notion of how to implement the beam dump is NOT good enough.
3. The whole lens / modematching situation for the 1064 and 532 paths will have to be redone so as to put the beam waists inside the Faraday crystal (NOT outside). The beam waist in the 4.7 mm diameter Faraday should be ~0.3-0.4 mm.
4. The efficiency that we got for the doubling shows that we don't need the cylindrical lenses - they are nice, but not needed to get 90% of the max power.
5. The lenses between the 1064 FI and the doubler should be put onto a base that can be used to adjust the lens position for MM optimization. Nothing fancy, just something slideable.
6. For this iteration of the table, we can do as Annalisa has written so as to get the green MM lenses ordered ASAP. After next week we can come up with a new plan before dismantling the EX table.

I aligned the green beam into the Faraday. I needed an HWP to have the right polarization for the light entering the Faraday itself.

I tried to dump as much beams as possible with razor dumps, but eventually I had to use some "temporary solutions" for higher beams, because I didn't find the right mounts for razor dumps.

I measured the beam waist after the Faraday with the beam scan. Analysis and MM calculation to follow.

Just so we have some numbers, I did a by-hand analysis of the PRMI sensing matrix numbers I posted here in the elog the other day.  This analysis is ignoring the error bar data.

For each sensor (PD_I or PD_Q), I do loop compensation, since these measurements were taken fairly close to the UGFs of the loops, and notches were not in use at the drive frequency.  To do the loop compensation, I multiply the complex value (lockin_I + i*lockin_Q) by (1-G), where G is the (complex) open loop gain of the degree of freedom I'm shaking.

 When I'm shaking a single degree of freedom (ex. shaking the PRM to get PRCL information), for each PD_I or PD_Q, we get 2 numbers, the lockin_I and lockin_Q values.    I check the phase between the lockin_I and lockin_Q values, since that phase (after loop compensation) should be either 0 or 180, and if it is not, something is wrong. 

Of the 16 sensors I measure (where PD_I and PD_Q count as 2 sensors), 11 sensors had phases more than 20 degrees away from either 0 or 180.  This is not good, and indicates that something is wrong with my measurement.  I suspect that I may not be driving hard enough -  I was using an amplitude 4x smaller than the previous value.  Next time the PRMI is locked, I will turn on the drive oscillation, and ensure that I can see the line in all of the PD signals.

The results of my quickie analysis script:

Bad REFL11_I_MICH phase!  Phase is -82.0185 degrees!
Bad REFL11_Q_MICH phase!  Phase is -35.9697 degrees!
Bad REFL33_I_MICH phase!  Phase is -134.952 degrees!
Bad REFL55_I_MICH phase!  Phase is -79.7997 degrees!
Bad AS55_I_PRCL phase!  Phase is -142.6016 degrees!
Bad AS55_Q_PRCL phase!  Phase is 90.6194 degrees!
Bad REFL11_I_PRCL phase!  Phase is 52.471 degrees!
Bad REFL11_Q_PRCL phase!  Phase is 52.2324 degrees!
Bad REFL33_I_PRCL phase!  Phase is 52.909 degrees!
Bad REFL33_Q_PRCL phase!  Phase is 25.14 degrees!
Bad REFL55_I_PRCL phase!  Phase is 52.8113 degrees!

Sensing Matrix, calculated even though most of the measurement data isn't any good:
AS55: MICH = 0.13502, -1.6122deg.  PRCL = 0.14993, -2.245deg
REFL11: MICH = 29.6373, -2.6365deg.  PRCL = 7376.3206, -2.9098deg
REFL33: MICH = 0.35649, -2.9633deg.  PRCL = 69.5133, -3.1302deg
REFL55: MICH = 0.62084, -2.0261deg.  PRCL = 75.0214, 3.1176deg

For now forget about the demodulation phase and assume all of the ports are independent.
I want to know the numbers in the following format.

          PRCL     MICH   (unit: cnt/m)
REFL11I:  x.xxxEx x.xxxEx
REFL11Q:  x.xxxEx x.xxxEx
REFL33I:  x.xxxEx x.xxxEx
REFL33Q:  x.xxxEx x.xxxEx
REFL55I:  x.xxxEx x.xxxEx
REFL55Q:  x.xxxEx x.xxxEx
REFL165I: N/A     N/A
REFL165Q: N/A     N/A
AS55I:    x.xxxEx x.xxxEx
AS55Q:    x.xxxEx x.xxxEx


If you really want to resolve the TF phase difference between the I and Q  demod-signals,
you need to look at the transfer functions between the excitation and these ports.
We can't understand what is happening only from the single point measurement.

So that I don't have to do loop compensation every time I measure a sensing matrix, I have put (back) in notches into FM10 of all the LSC filter banks, except MC2.  

MICH already had this notch, PRCL and CARM both had it, although it was mislabeled in the filter title as "Notch410" rather than the truth, which is "Notch628". 

The XARM and YARM filter banks were full, since we have not (in those filter banks) combined all of the resonant gains - 3.2Hz, 16Hz, 24Hz - into one module.  I took out a CLP3000 (  cheby1('LowPass",2,3,3000)gain(1.41254)  ) in each of those filter banks, and put in the notch.

I also have changed the band pass filters in the LSC-Lockin#_SIG filter banks to match this new drive frequency.

The PRMI sensing matrix, as measured last Thursday, in a more readable format:

EDIT: DON'T Look at this yet!  I forgot to calibrate it!  Please hold.....

            PRCL          MICH        
AS55_I      1.228E-01     5.476E-03    
AS55_Q      1.547E-01     1.345E-01    
REFL11_I    9.946E+03     8.106E+01    
REFL11_Q    2.346E+03     2.707E+01    
REFL33_I    9.639E+01     8.717E-01    
REFL33_Q    9.707E-01     6.626E-02    
REFL55_I    1.040E+02     8.464E-01    
REFL55_Q    2.018E+00     5.803E-01

Okay, Calibrated, but forgot to include loop compensation (since notches didn't exist yet):

Sensing Matrix, units = cts/meter
 
            MICH          PRCL        
AS55_I      5.024E+08     9.418E+07    
AS55_Q      6.328E+08     2.313E+09    
REFL11_I    4.068E+13     1.394E+12    
REFL11_Q    9.594E+12     4.656E+11    
REFL33_I    3.942E+11     1.499E+10    
REFL33_Q    3.970E+09     1.140E+09    
REFL55_I    4.253E+11     1.456E+10    
REFL55_Q    8.252E+09     9.981E+09

There was an issue with running the new summary pages, because laldetchar was not included (the website I used for instructions doesn't mention that it is needed for the summary pages).  I figured out how to include it with help from Duncan.  There appear to be other needed dependencies, though.  I have emailed Duncan to ask how these are imported into the code base.  I am making a list of all the packages / dependencies that I needed that weren't included on the website, so this will be easier if/when it has to be done again.

controls@rossa:~ 0$ ping 192.168.113.222
PING 192.168.113.222 (192.168.113.222) 56(84) bytes of data.
From 192.168.113.215 icmp_seq=2 Destination Host Unreachable
From 192.168.113.215 icmp_seq=3 Destination Host Unreachable
From 192.168.113.215 icmp_seq=4 Destination Host Unreachable
From 192.168.113.215 icmp_seq=5 Destination Host Unreachable
From 192.168.113.215 icmp_seq=6 Destination Host Unreachable
From 192.168.113.215 icmp_seq=7 Destination Host Unreachable
From 192.168.113.215 icmp_seq=9 Destination Host Unreachable
From 192.168.113.215 icmp_seq=10 Destination Host Unreachable
From 192.168.113.215 icmp_seq=11 Destination Host Unreachable
64 bytes from 192.168.113.222: icmp_seq=12 ttl=64 time=10341 ms
64 bytes from 192.168.113.222: icmp_seq=13 ttl=64 time=10335 ms
^C
--- 192.168.113.222 ping statistics ---
35 packets transmitted, 2 received, +9 errors, 94% packet loss, time 34021ms
rtt min/avg/max/mdev = 10335.309/10338.322/10341.336/4.406 ms, pipe 11
controls@rossa:~ 0$ 

This has not been fixed!

Temporary solution: I ssh'd to nodus from the 40m wifi network and was able to connect to the FE machines.This works but the bandwidth is limited this way as expected.

40m MARS network needs to be fixed.

 The bridge support posts were shimmed today. Surgical tubing 402R - o - rings were glued togeather with " instant krazy glue "

Atm2  Carey CH-3540 latches are compressed ~2.5 mm in the clamped position.

Atm3 is showing the captured quick release pin in the steel reinforced bridge that is supported by the post. It works great. The post screw is sealed by o-ring. The quick-pin is sealed by an epoxy attached copper cap.

Atm4 Enclosure is on it's back. Bottom o-ring can be seen. The hole reinforced bridge structure is visible.

Now I'm working on the window connection to the chamber. I'm very close leak checking this box.

In case of leaking around the top tubing seals we have two options:

a, cut down on the cover rim by 0.040"  or b, increase tubing diameter

X arm aligned to green.

Aligned the X arm to IR.
Used steering mirrors to align the X end green to the X arm while remaining locked for IR. X arm locks to green stably with GTRX at the PSL table measuring 235uW and corresponds to 2560counts in C!:ALS-TRX_OUT.

Next
1. PSL green alignment.
2. Search for beat note.
3. Resurrect ALS for X arm.

I did a bunch of cleanup work on the netGPIB stuff:

• Removed extensions from all executable scripts (executables should not have language extensions)
• fixed execution permissions on executables and modules
• committed HP8590.py and HP3563A.py instrument modules, which were there but not included in the svn
• committed NWAG4395A (was AG4395A_Run.py) to svn, and removed old "custom" copies (bad people!)
• cleaned up, modernized, and fixed the netgpibdata program
• removed plotting from netgpibdata, since it was only available for one instrument, there's already a separate program to handle it, and it's just plotting the saved data anyway
• added a netgpibcmd program for sending basic commands to instruments.
• added a README

Probably the most noticeable change is removing the extensions from the executables.   There seems to be this bad habit around here of adding extensions to executables.  It doesn't matter to the person running the program what language it was written in, so don't add extensions.  It only matters for libraries.

The PRMI sensing matrix scripts have been modified to output a sensing matrix which is calibrated into units of counts/meter.

To run, you should just need to run .../scripts/LSC/runPRMI_SENS.py . 

If it looks like the drive amplitude is not large enough (no nice peak in the photodiode signals), you can increase the drive amplitude, which is line 21 in runPRMI_SENS.py  

X-green and PSL green have been aligned so that they interfere at the beat PD for X.

I haven't scanned the X-end NPRO temperature to find the beat note. I found the earlier elog when this was done (elog 6851) and will use those temperatures to start with.

It was too embarassing to see that the actuation frequency was set at the violin mode frequency in order to avoid designing a new filter!?

I ran Jenne's sensing matrix code and the immitated the same result by manual measurement with DTT.
I noticed that the PRM excitation was not transmitted to the mirror. I tracked down the cause and found that
Jenne is using 628Hz which is the notch frequency of the viloing filter.

There is no way we can measure the precise calibration of the error signal exactly at the violin mode frequency.

Nevertheless I waited for the ringdown of the violin mode to the floor level and ran the code again WITH the violin mode filter OFF
at PRM SUS.

The result was stored in the data file

sensematPRM_2013-05-22.12615.dat

The code spit the message at the end

Sensing Matrix, magnitude only, units = cts/meter
 
            MICH          PRCL         
AS55        5.304E+08     1.716E+09     
REFL11      1.732E+13     2.151E+11     
REFL33      1.616E+11     5.384E+09     
REFL55      1.681E+11     6.950E+09

Now I replicated the same measurement with DTT.

MICH or PRCL were excited with the lockin. In order to aviod the violin mode, I shifted the excitation freq by 1Hz. (i.e. 629.125Hz)

The peaks in REFL33I/Q and RFL55I/Q were observed with PSD and TF. The spectrum was measured with the FLATTOP window with the line resolution of 0.1Hz
DTT suggested that this corresponds to the BW of 0.471271Hz if I correctly understood what DTT plot said. We need this information to convert cnt/rtHz to cnt_pk
if we need. For the TF measurements, I needed to find the excitatin monitor but I could not. Therefore, I set the offset of LSC-LOCKIN1_SIG to be 1000,
so that C1:LSC-LOCKIN1_I_IN1 produce the same signal as the excitation.

Note that during the measurement, 628Hz nothces in the LSC servos were on. I confirmed that this provides the reduction of the feedback by a factor of 76.
As the original openloop gain at 629Hz is lower than the unity more than a factor of 2, this was sufficient attenuation to measure the optical gain with the systematic error of less than a %.

MICH excitation (ITMX -1, ITMY +1)
        PSD (cnt/rtHz)   TF Mag    Phase
REFL33I 0.098590         9.5691e-5 74.4344
REFL33Q 0.019294         1.8665e-5 71.1204
REFL55I 0.016123         1.3890e-5 77.3132
REFL55Q 0.157522         1.5285e-4 91.5594

PRCL excitation (PRM +1)
        PSD (cnt/rtHz)   TF Mag    Phase
REFL33I 15.7565          1.5298e-2 -109.727
REFL33Q  0.171648        1.6310e-4 -141.73
REFL55I 16.2834          1.5809e-2 -109.672
REFL55Q  0.634096        6.1012e-4 -143.169


These measurements are saved in the XML files (for DTT) in
/cvs/cds/caltech/users/koji/130521/
as
130521_MICH_EXC.xml and 130521_PRCL_EXC.xml

As the actuator of the PRM/ITMX/ITMY are {19.6, 4.70, 4.66}/f^2 nm/cnt, the optical gains were calculated from the TF measurements.

MICH excitation (ITMX -1, ITMY +1)
        OPTICAL GAIN (cnt/m)
REFL33I 4.0e9
REFL33Q 7.9e8
REFL55I 5.9e8
REFL55Q 6.5e9


PRCL excitation (PRM +1)
        OPTICAL GAIN
REFL33I 3.1e11
REFL33Q 3.3e9
REFL55I 3.2e11
REFL55Q 1.2e10

These should be compared with the measurement by the script and we get more information from the script (like AS55, REFL11)

After the results of the analysis in the #8598 thread, I have added the "no_zero_pad=1" flag to the cdsParameters block of all SUS models:

• c1mcs
• c1sus
• c1scx
• c1scy

The upsampling to the 64 kHz DAC output will now be done with sample-holds, instead of zero-pads.  This should reduce the 32 kHz lines we were noticing in the analog DAC output.

I note, though, that Brian Lantz points out that this might actually introduce a delay of about a half sample.  We will continue to investigate.

In any event, I have rebuilt and installed all models listed above.  I will restart as soon as opportunity allows.

I fiddled around with the QPD that I'll use to replace Koji's temporary razor blade yaw sensor for detecting POP beam angular motion, and checked that it is working. 

Using the Jenne Laser, I put beam onto the 4 different quadrants of the QPD, and saw that the Sum channel remained constant. 

   * I had the room lights off, since the PD elements are silicon. 

   * Beam size on the QPD as seen on an IR card was ~1mm diameter.

   * With the beam on the QPD, I chose gain setting "G2" on the amplifier, since that was the only setting where neither the "current too high" nor the "current too low" LEDs were illuminated.  I didn't measure the power going to the PD, but the Jenne Laser puts out 1.2mW, and there's a 50/50 BS, so I was getting about 600uW. 

   * I turned off the "zero/cal" switch on the back of the box, since I don't know how to set the zero.  Since the X and Y channels are normalized by the Sum, you can't just block all light going to the PD and set the zero.  There isn't a big change in the output levels with the zero/cal switch off, so I think it should be fine.  (Previously, I set all 4 knobs - "zero" and "cal" for each X and Y - to approximately the center of their ranges.  Once you hit the end of the range, you can keep turning the knob, but something inside makes a clicking sound ~once per revolution, and the signal level stops changing (for the zero knobs). Much like centering a beam on a PD, I found each edge of the range for each knob, and set the knobs in the centers by counting the number of turns.  Anyhow, since I set the knobs to ~halfway, I think that explains why there isn't really a change whether the "zero/cal" switch is on or off.

   * Using the steering mirror sending the beam to the QPD, I moved the beam around, and watched where I was going with an IR viewer.  I see that as I move from quad-to-quad, the X and Y channels respond as I expect.  If I only move the beam in X, I only see X response on a 'scope, and vice versa.

I can't do a real calibration until I get the QPD installed in place, so I can use the actual beam, but for now it looks like the QPD is responding nicely.  Since Annalisa and Manasa are using the Arms for the evening, I'll work on putting the QPD on the POX table tomorrow.

 To avoid exciting at the PRM violin mode frequency, I have changed all of the filters relevant to the sensing matrix measurement from 628Hz to 580.1Hz.  This includes notches in the LSC control loops, as well as the band pass filters in the lockins.  I have not yet loaded the new filters, since arm locking is in progress.

 Ooops, definitely my bad.  I think I was the one who put in the PRM violin filter, so I should have recognized that frequency.  However, I couldn't think of a reason why violin mode filters should be in the LSC filter banks, since we usually put them in C1:SUS-optic_LSC filter banks. 

Anyhow, so that I don't make a mistake like that again, I was looking through all of the violin mode filters for all the optics, so I could write down the frequencies.  The result: confusion.

Violin filters in C1:SUS-optic_LSC filter banks:

The PRM's violin mode filter is set correctly to 627.75Hz:  elog 8533.

One of BS or SRM has probably been measured (presumably BS), since they have the same filters centered around 645Hz. 

Neither ITM has a violin filter.

The ETMs have violin filters in the 440's, which I assume was correct back in the MOS days, before 2010.

Vio2 filters in C1:SUS-optic_LSC filter banks:

PRM, SRM, BS, ITMX, ITMY:  Centered around 1285 Hz, which matches the violin notch frequencies in the BS and SRM.

ETMY:  Centered around 883.5Hz, which matches the old 440Hz frequency

ETMX:  Centered around 631Hz .  So, this could have been measured, but it was put into the wrong filter module.

Koji tells me that we don't really need to worry about all these violin filters unless they are required (as with the PRM and the obnoxious hum a few weeks ago), so I 'm not going to do any measuring / adjusting of these filters for now.

I am trying to re-analyze the data that Koji took last night.  

I think that my script is just pulling out the I and Q data for each port, and each degree of freedom, calculating the magnitude from sqrt( I**2 + Q**2 ) and the phase from atan2( I / Q ).  No calibration.

If I print out the results, I get:

Sensing Matrix, units = cts/ct, phase in degrees
 
            MICH Mag   MICH Phase    PRCL Mag   PRCL Phase  
AS55_I      1.627E-02   62.063        4.189E-03   68.344       
AS55_Q      2.073E-02  -105.353        1.983E-02   66.361       
REFL11_I    8.165E+02  -112.624        2.441E+00   77.911       
REFL11_Q    2.712E+02  -112.650        7.065E-01  -127.093       
REFL33_I    8.028E+00  -112.154        6.282E-02   70.990       

REFL33_Q    5.490E-02  -165.912        9.908E-03   61.269       


REFL55_I    8.347E+00  -112.085        2.146E-02   78.928       
REFL55_Q    3.003E-01  -151.652        7.924E-02   87.153  

If, however, I take the raw values that are stored in the data file, for one row (say, REFL33_Q) and calculate by hand (same formulas), I get different results:

            MICH Mag   MICH Phase    PRCL Mag   PRCL Phase  
REFL33_Q    9.9E-03    28.89         5.46E-02   -103.8

Contrast that with Koji's uncalibrated transfer function result from elog 8611:

            MICH Mag    MICH Phase    PRCL Mag     PRCL Phase  
REFL33Q     1.8665e-5   71.1204       1.6310e-4    -141.73

I am currently confused, and need to re-look at my script, as well as make sure I am actually measuring the things I think I am.

EDIT:  This has been fixed, in that my 2 calculations agree with one another.  I have crossed out the incorrect numbers, and put correct numbers below.  I still don't agree with Koji, but at least I agree with myself. 

The phase issue:  I needed to calculate the phase with "ATAN2(I,Q)", which I did when I calculated by hand, but the script had "atan2(Q,I)".  This has been fixed. 

The magnitude issue:  They match, but my "pretty print" script labels MICH as PRCL, and vice versa.  Doh.

Corrected values:

Sensing Matrix, units = cts/ct, phase in degrees
 
            PRCL Mag   PRCL Phase    MICH Mag   MICH Phase  
AS55_I      1.627E-02    27.937      4.189E-03    21.656     
AS55_Q      2.073E-02  -164.647      1.983E-02    23.639     
REFL11_I    8.165E+02  -157.376      2.441E+00    12.089     
REFL11_Q    2.712E+02  -157.350      7.065E-01  -142.907     
REFL33_I    8.028E+00  -157.846      6.282E-02    19.010     
REFL33_Q    5.490E-02  -104.088      9.908E-03    28.731     
REFL55_I    8.347E+00  -157.915      2.146E-02    11.072     
REFL55_Q    3.003E-01  -118.348      7.924E-02     2.847 

 [Annalisa, Koji] 

 GREEN

I aligned back the beam (we lost part of the alignment after we put back the box and after the posts were installed). The green beam out from the crystal is still low, but anyway I get about 1.2 mW of green out from the Faraday. 

TO DO 

Mode Matching calculation (tomorrow)

Fix the dumping situation

Replace some of the mounts with more solid ones (in the future)

TRANSMON PATH

 QPD, PD and Camera have been rotated as Rana suggested last Wednesday. A 1m focal length lens is on the main beam transmitted path (before the harmonic separator), and the beam diameter on the QPD is about 5mm. We put another lens with a shorter focal length to put the PD very close to the beam waist and in way to have a reasonable beam size on the camera. Tomorrow I will write down all the correct sizes of the beams.

OPLEV 

(for Steve) I marked a possible beam path for the Oplev (the laser is not in the right place in the picture, but I left it in the correct place on the table). I also put the QPD for the IP-ANG, so we know in which part of the table the beam can be steered.

The space in the red rectangle (right corner) has to be left empty to put a PD for the rejected beam from the green Faraday.

 I have loaded these new filters in.  Manasa is still using the IFO for green stuff, so I can try out the PRMI measurement in a day or so.  (Right now I have to make sure I understand my data, anyway.)

I have restarted all the suspension models with the new no_zero_pad flag for the DAC upsampling.  Everything came up fine and all optics are damped as expected (except for concerns about c1scy which I'll note in a followup).

Some strong seismic noise (not related to any earthquakes - watchdogs are all green) had got the MC unlocked this morning.

I found the MC autolocker and MCWFS disabled. Enabling them locked the MC right away. I don't see any updates in the elog  as to why these were left disabled and hence have left them ON now.

 Temporary oplev in place. The spot on the qpd is still big. My two lens solution did not work.

I will finalize optical component position of the oplev after the the arm transmitted and green beam optics in place. They have priority.