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ID Dateup Author Type Category Subject
  10513   Wed Sep 17 13:41:00 2014 JenneUpdateSUSNew calibrated channels for test QPD

Steve asked about calibrating the QPD, so I set up some new epics records so that we can have calibrated versions of the QPD output.

The new channels are called C1:ASC-TESTQPD_Y_Calc and C1:ASC-TESTQPD_X_Calc for pitch and yaw, respectively.


Details:

 * I modified /cvs/cds/caltech/target/c1iscaux/QPD.db to add 2 new channels.  Since we are currently plugged into the IPPOS channels, I didn't want to modify the units of IPPOS, which is why I created new channels.  The new channels are just the IPPOS normalized X and Y channels, multiplied by a calibration factor.  Steve has already done a rough calibration for his setup, so I used those numbers (0.15 urad/ct for pitch and 0.25 urad/ct for yaw). 

* Rebooted c1iscaux.  This required adding it to chiara's /etc/hosts file.

* Added the channels to the /opt/rtcds/caltech/c1/chans/daq/C0EDCU.ini file so that the channels would appear in dataviewer.

* Restarted the framebuilder daqd process.


How to modify the calibration:

1) On a control room workstation, cd /cvs/cds/caltech/target/c1iscaux to get to the right folder.  (Note that this is still in the old cvs/cds place, *not* the new opt/rtcds place)

2)  open the epics database file by typing sudo emacs QPD.db.  Since this is a protected file, you need to use the "sudo" command, and will have to type in the usual controls password. 

3)  Find the "records" that have the channel names C1:ASC-TESTQPD_Y_Calc and C1:ASC-TESTQPD_X_Calc by scrolling down.  (Right now they are on lines #550 and #561 of the text file).

4) For each of these 2 records, modify the calibration in the line that says something like field(CALC,"(A*0.25)").  In this example, the current calibration is 0.25 urad/oldCount.  Change the number to the new value.

5) Save the file.  If you followed the procedure in step2 and used the emacs program and you can't use the mouse, do the following:  Hold down the "ctrl" key.  Keeping ctrl pushed down, push the "x" key.  Still keeping ctrl pushed down, push the "s" key. 

6) Close the file.  If you followed the procedure in step2 and used the emacs program and you can't use the mouse, do the following:  Hold down the "ctrl" key.  Keeping ctrl pushed down, push the "x" key.  Still keeping ctrl pushed down, push the "c" key. 

7) Reboot the slow computer called c1iscaux.  You should be able to do this remotely by typing telnet c1iscaux, and then typing reboot.  If that doesn't work, you may have to go into the IFO room and power cycle the crate by turning the key.  This computer is in 1Y3, near the bottom.

8) Check that you can see your channels - you should be finished now!

For steps 3 and 4, here is a screenshot of the lines in the text file:

NewQPDcalibratedChans.png

  10514   Wed Sep 17 15:40:00 2014 ericqUpdateLSCDRMI locking

I have not had any success the past two days in getting an interferometric measurement of the SRC length. 

So, the question posed at today's meeting was: "How precisely do we need to change the SRC length to be able to lock the DRMI on 3F"

The two ways I could think to quantify this are:

  • How much MICH -> [S,P]RCL cross coupling is ok?
  • How much [S,P]RCL ->  MICH cross coupling is ok?

REFL33 should have its phase set to put PRCL along I, and REFL165 should have SRCL along I, so the simulation result that matters is the angle of MICH in these planes. The cross couplings are then given by the appropriate trigonometric projections. In the following plots, I used 10% as the acceptable cross coupling in either direction. 

Result:

dcAngleDiff_srcL.pdf

Thus,

  • To limit the MICH -> [S,P]RCL coupling to 10%, we must hit the ideal length within +- 1.2cm.
  • To limit the SRCL -> MICH coupling to 10%, we must hit the ideal length within +- 2mm.
  • It doesn't look like we can get the REFL33 angle totally to 90 degrees, REFL165 looks more promising.

Code (finesse + pykat + ipython notebook) and plots are attached. 

  10515   Wed Sep 17 18:36:03 2014 KojiHowToGeneralHow to run DTT measurement automatically
  • Suppose you have a dtt template name test.xml
  • The file test.dtt

    open
    restore test.xml
    run -w
    save test2.xml
    quit
     
  • Run diag < test.dtt
  • The result is saved in test2.xml
  10516   Thu Sep 18 02:42:28 2014 JenneUpdateLSCAO path partly engaged

Tonight was a night of trying to engage the AO path.  The idea was to sit at arm powers of a few on sqrtInvTrans for CARM and ALS for DARM, and try to increase the gain for REFLDC->AO path.

No exciting nit-picky details in locking procedure.  Mostly it was just a night of trying many times. 

The biggest thing that Q and I found tonight was that the 2-pin lemo cable connecting the CM board's SERVO OUT to the MC board's IN2 is shitty.  The symptom that led to this investigation was that I could increase the AO path gain arbitrarily, and have no change in the measured analog CM loop transfer function. We checked that the CM board servo out spit out signals that were roughly what we expected based on our ~2kHz excitation.  However, if we look at digitized signals from the MC board, the noise level was very high, with loads of 60Hz lines, and a teensy-tiny signal peak.  We put a small drive directly into the MC board and could see that, so we determined that the cable is bad.  We have unplugged the white 2-pin lemo, and ran a long BNC cable between the 2 boards.  Tomorrow we need to make a new 2-pin lemo cable so that we can have the lower noise differential drive signal.

After putting in the temporary cable, we do see an excitation sent to the CM board showing up after the MC board.  For this monitoring, the MC_L cable to the ADC has been borrowed, so instead of being the OUT1, the regular length signal, MC_L is currently the OUT2 monitor right after the board inputs. 

At some point in the evening, around 1:15am, ETMX started exhibiting the annoying behavior of wandering off sometimes.  I went in and pushed on the SUS cables to the satellite box, and I think it has helped, although I still saw the drift at least once after the cable-squishing.

Other than that, it has just been many trials.

The best was one where I was holding the arm powers around 4, and got the CM board's AO gain to -8 dB and the MC board's IN2 AO gain to -4 dB. I lost lock trying to increase the CM board gain to -7 dB. 

I took several transfer functions, and used Q's nifty "SRmeasure" script to gather data, and Q made a plot to see the progress.

TF progress plots:

0020.pdf

Time series of that lockloss:

Zoom_TRXTRY4_EngagingAO_1095059162.png

I don't know yet if the polarity of the CM board should be plus or minus.  This series was taken with "minus".  But,  since the phase looked opposite of Q's single arm CM board checkout from several months ago, we did a few trials with the polarity switched to "plus".  I thought we weren't getting as high of AO path gains, so I switched back to "minus", but the last few trials didn't get even as far as the plus trials did.  So, I still don't know which sign we want.

  10517   Thu Sep 18 09:17:47 2014 SteveUpdateSUSHeNe laser test

TEST QPD sn 222 was calibrated with 1103P directly looking into it from 1 m. ND2 filter was on the qpd.

 

  10518   Thu Sep 18 10:08:07 2014 steveSummarySUSoplev laser summary updated

 

Quote:

 

Quote:

 

                  2005              ALL oplev servos use Coherent DIODE LASERS # 31-0425-000, 670 nm, 1 mW

    Sep. 28, 2006              optical lever noise budget with DC readout in 40m,  LIGO- T060234-00-R, Reinecke & Rana

    May  22, 2007              BS, SRM & PRM  He Ne 1103P takes over from diode

    May  29, 2007              low RIN He Ne JDSU 1103P selected, 5 purchased sn: T8078254, T8078256, T8078257, T8078258 & T8077178 in Sep. 2007

    Nov  30, 2007               Uniphase 1103P divergence measured

    Nov. 30, 2007               ETMX old Uniphase 1103P  from 2002 dies: .............., running time not known......~3-5 years?

    May 19, 2008               ETMY old Uniphase 1103P from 1999 dies;.....................running time not known.....~    ?

    Oct.  2, 2008                ITMX & ITMY are still diodes, meaning others are converted to 1103P earlier

 

                     JDSU 1103P were replaced as follows:

   May 11, 2011                ETMX replaced, life time 1,258 days  or 3.4 years

   May 13, 2014               ETMX , LT 1,098 days or 3 y

   May 22, 2012               ETMY,  LT 1,464 days or  4 y

   Oct.  5, 2011                BS & PRM, LT 4 years,  laser in place at 1,037 days or 2.8 y

   Sep. 13, 2011               ITMY  old 1103P &    SRM    diode laser replaced by 1125P  ..........old He life time is not known, 1125P in place 1,059 days or 2.9 y

   June 26, 2013              ITMX 622 days or 1.7 y    note: we changed because of beam quality.........................laser in place 420 days or 1.2 y

 

  Sep. 27, 2013               purchased 3 JDSU 1103P lasers, sn: P893516, P893518, P893519 ......2 spares ( also 2 spares of 1125P of 5 mW & larger body )

 

      May  13, 2014             ETMX,  .............laser in place 90 d

      May  22, 2012             ETMY, 

     Oct.  7,  2013             ETMY,  LT  503 d  or  1.4 y............bad beam quality ?

     Aug. 8,  2014              ETMY,  .............laser in place   425 days  or  1.2 y

 

      Sept. 5, 2014              new 1103P, sn P893516  installed at SP table for aLIGO oplev use qualification

     

  10519   Thu Sep 18 17:44:55 2014 JenneUpdateLSCOld AO cable pulled

[Q, Jenne]

We pulled the old 2-pin lemo cable after I had a look at the connectors.  When I unscrewed the connector on the MC side, one of the wires came off.  I suspect that it was still hanging on a bit, but my torquing it finally killed it. 

We pulled the cable with the idea of resoldering the connectors, but there are at least 2 places where the cable has been squished enough that the shielding or the inner wires are exposed.  These places aren't near enough the ends to just cut the cable short.

Downs doesn't have a spool of shielded twisted single-pair cable, so Todd is going to get me the part number for the cable they use, and I've asked Steve to order it tomorrow. 

For now, we will continue using the BNC cable that we installed last night - I don't think it's worth resoldering and putting in a crappy 2-pin lemo cable that we'll just throw out in a week.

  10520   Fri Sep 19 04:05:05 2014 ericqUpdateLSCAO path partly engaged

More AO efforts. No huge news. 

Came at AO from each side. For each sign, I lost lock just a few dB from the AO portion of the loop crossing unity gain. Both attempts were about arm powers of 1, which should correspond to ~300pm CARM offset, which I have simulated the crossover as possible with my current loop models (including latest MC loop). The gain steps were usually 6dB in between measurements. 

Positive polarity on CM board screen:

I made it to +5 dB of the last plot here, but the 6th broke it open. Gains on CM In2, CM AO, and MC In2 were -6, -4, -2 on that last, lock breaking, step. 

TFSR785_19-09-2014_020555.pdf

Negative polarity on CM board screen:

Lost it just 2dB above the last trace. Gains were -6, +1, -2 (So, overall 5dB higher than the other polarization)

TFSR785_19-09-2014_033920.pdf

Many things happened in between these two lock stretches, but I'm not sure what may or may not have affected things. They include:

  • Jenne mentioned PRMI being fussy earlier in the evening. I adjusted REFL33 and POP22 angles during a PRMI lock, while CARM was held away with ALS. My simulations suggest that there are small changes to the 3F sensing when the arms are totally absent, but doing it at a finite CARM offset is closer to where we want it, it seems. 
  • I tried using REFL165Q for MICH, since my simulations suggest a better MICH/PRCL angle, which would stave off cross couplings. Lined up excitations, etc., but no luck. 
  • I measured the PRMI loops
    • found PRCL to have ~200Hz UGF, 8dB gain peaking. Maybe a little high, but didn't seem terrible. 
    • MICH had UGF of around 20Hz, with the FM gain at 0.8. By the shape of the phase bubble, the loop seems designed for higher bandwidth. I raised the gain to 2.5 for a 70ishHz UGF, and called in FMs 7 and 9 for additional triggered boosts. Things seemed to stay locked pretty well. 
  • Lower excitation amplitude the second time around, measuring the AO loop. Looking at the CM output spectra, you can see the excitation wailing away; I wanted to avoid it.

The location of the CARM resonance peak lines up with my simulation, which is good, but there appears to be less phase than expected... I tried making sure that we don't have any whitening uncompensated for, but it looked ok. All my AO path loop model contains is the CM board TF (measured and fitted), the IMC seen as an actuator(measured and fitted), and the REFLDC optical TF (simulated in MIST). Maybe the DC path of whatever diode this is coming from needs to be included...

Discontinuities / glitches could be seen in the CM board fast output when MC board gains were changed, which isn't so nice. Incidentally, I notice now that each lock loss corresponded to a step of AO gain on the CM board.

  10521   Fri Sep 19 13:12:07 2014 JenneUpdateLSCAO path glitches

Quote:

Discontinuities / glitches could be seen in the CM board fast output when MC board gains were changed, which isn't so nice. Incidentally, I notice now that each lock loss corresponded to a step of AO gain on the CM board.

Back in May I looked at all the glitches that happen when we change the AO gain slider on the CM board - see elog 9938.   I wonder if the MC IN2 gain slider has the same issues.  I think I'll look at this this afternoon. Maybe we can set the CM board gain someplace, and just use the MC IN2 slider (if it's not as glitchy) for the delicate part where we're just about to cross unity, and then later we can again use the CM board's AO gain.

EDIT:  Yes, the glitches on the CM board AO path are *much* bigger, and more frequent.  Interestingly, the biggest glitches were every 4 dB.  When I went from -29 to -28, again from -25 to -24, -21 to -20, etc.  I saw the largest glitches on the MC IN2 slider going -29 to -28 and -17 to -16, but if there were small glitches at other transitions, they didn't hit my trigger levels.  I think next time I try engaging the AO path I'll try to do the delicate stuff by upping the MC IN2 gain rather than the CM board AO gain.

  10522   Mon Sep 22 10:14:07 2014 SteveUpdateSUSHeNe laser test

Quote:

TEST QPD sn 222 was calibrated with 1103P directly looking into it from 1 m. ND2 filter was on the qpd.

 

 

  10523   Mon Sep 22 10:18:58 2014 steveUpdatePEMlab temperatures

 

 

  10524   Mon Sep 22 15:20:32 2014 SteveUpdateVACRGA scan at day 229

 

 

  10525   Tue Sep 23 08:34:14 2014 SteveUpdateSUSHeNe laser test

 

 The room temp drops 1 degree C on the 4th day. The weather has changed.

  10526   Tue Sep 23 09:37:12 2014 SteveUpdateSUSIOO and temp changes
  10527   Tue Sep 23 17:37:10 2014 ericqUpdateLSCDRMI locking

Rather than using a CAD drawing, I used Gabriele's code from ELOG 9590 to try and judge if we could shorten the SRC by the appropriate length, without clipping the SR3-SR2 beam. 

Specifically, I used these lines:

% Move SRM 7.5 towards SR2, parallel to beam

delta=75;

dAS = BS2-AS; Vector from SRM to SR2

dASmag = sqrt(dAS(1)^2+dAS(2)^2);

dMove = delta*dAS/dASmag;  delta times unit vector

CS = CS+dMove;

draw_sos(CS, 180/pi*angles)

 
to help generate this plot:

SRCcorrection.pdf

 


As a reminder, Gabriele's code used the following logic:

  • We know the nominal dimensions of all of the suspensions
  • We hand measured various distances between features of the suspension structures. (Corner to corner)
  • A global fit, minimizing the maximum error, reconstructed the positions of the suspensions. 
  • Beam positions assumed to be ideally aligned. 
  • Beam trajectories traced out, and optical path lengths estimated (taking into account changing indices of refraction due to flipped mirrors)

In my opinion, this is the best estimate of beam trajectory that we currently have.

Thus, from looking at the plot above, I claim we can correct the SRC length without clipping the beam by moving the SRM forward by the required 7.5cm.

Although the measured distance may be off on the order of a cm (since our PRC correction had a 0.5cm disagreement between interferometric and hand distance measurements), this will nevertheless markedly improve our 3F DRMI sensing, based on my previous ELOG. 

 


Hence, given our discussions last week, Jenne and I will proceed to ready the interferometer for venting in the morning, by following the vent checklist.

Our sole objective for this vent is this move of the SRM. 

Steve, please check the jam nuts, and begin the vent when you get in.  Thanks!

  10528   Tue Sep 23 17:56:13 2014 Jenne, EricQUpdateGeneralVent prep for SRC length change

As Q mentioned in elog 10527, (prompted by Koji's email this afternoon) we are prepping the IFO for vent.  Here is a copy of the pre-vent checklist from the wiki, updated as we work:

 

Pre-vent checklists

 
  1. Center all oplevs/IPPOS/IPANG
  2. Align the arm cavities for IR and align the green lasers to the arms.
  3. Make a record of the MC pointing
  4. Align the beam at the PSL angle and position QPDs
  5. Reduce input power by adjusting wave plate+PBS setup on the PSL table BEFORE the PMC. (Using the WP + PBS that already exist after the laser.)
  6. Replace 10% BS before MC REFL PD with Y1 mirror and lock MC at low power.
  7. Close shutter of PSL-IR and green shutters at the ends
  8. Make sure the jam nuts are protecting bellows

Notes:

1 & 2:  Locked arms on IR, ran ASS.  Unlocked IFO, aligned PRM for good POP flashes, aligned SRM for symmetric AS flashes.  Aligned all oplevs.  Used PZTs to align Xgreen to arm. Used knobs to align Ygreen to arm.  With PS:L green shutter closed, Xgreen  = 0.520, Ygreen = 0.680.

3:  Moved MC servo output cable that goes to ADC from OUT2 (which we had been using for monitoring AO path signals) back to its usual OUT1 (which is MC_L).  This is used in the spot position measurement script.  Spots at:  [2.32, -0.50, 1.97, -1.11, 0.26, -1.86] mm.

4: Done -Q

5:  Removed a PD that was monitoring the light coming backwards through the Faraday that sits just after the laser, just in case (confirmed that beam dump behind PD was catching beam).  Other port of PBS just had regular black hole dump.  Adjusted half wave plate until we had ~90mW just before injection into the vacuum.

6: Completed. Locked MC manually at transmission of ~1150, but low power autolocker isn't working. This isn't a critical thing, and can be fixed at any point during the vent. -Q

7: Shutters closed. Ready for Steve to check nuts and begin venting! -Q

  10529   Wed Sep 24 08:39:32 2014 Jenne, EricQUpdateGeneralVent prep for SRC length change

Quote:

As Q mentioned in elog 10527, (prompted by Koji's email this afternoon) we are prepping the IFO for vent.  Here is a copy of the pre-vent checklist from the wiki, updated as we work:

 

Pre-vent checklists

 
  1. Center all oplevs/IPPOS/IPANG
  2. Align the arm cavities for IR and align the green lasers to the arms.
  3. Make a record of the MC pointing
  4. Align the beam at the PSL angle and position QPDs
  5. Reduce input power by adjusting wave plate+PBS setup on the PSL table BEFORE the PMC. (Using the WP + PBS that already exist after the laser.)
  6. Replace 10% BS before MC REFL PD with Y1 mirror and lock MC at low power.
  7. Close shutter of PSL-IR and green shutters at the ends
  8. Make sure the jam nuts are protecting bellows

Notes:

1 & 2:  Locked arms on IR, ran ASS.  Unlocked IFO, aligned PRM for good POP flashes, aligned SRM for symmetric AS flashes.  Aligned all oplevs.  Used PZTs to align Xgreen to arm. Used knobs to align Ygreen to arm.  With PS:L green shutter closed, Xgreen  = 0.520, Ygreen = 0.680.

3:  Moved MC servo output cable that goes to ADC from OUT2 (which we had been using for monitoring AO path signals) back to its usual OUT1 (which is MC_L).  This is used in the spot position measurement script.  Spots at:  [2.32, -0.50, 1.97, -1.11, 0.26, -1.86] mm.

4: Done -Q

5:  Removed a PD that was monitoring the light coming backwards through the Faraday that sits just after the laser, just in case (confirmed that beam dump behind PD was catching beam).  Other port of PBS just had regular black hole dump.  Adjusted half wave plate until we had ~90mW just before injection into the vacuum.

6: Completed. Locked MC manually at transmission of ~1150, but low power autolocker isn't working. This isn't a critical thing, and can be fixed at any point during the vent. -Q

7: Shutters closed. Ready for Steve to check nuts and begin venting! -Q

 

  10530   Wed Sep 24 08:40:29 2014 SteveUpdateVACVent has started

 

 Jam nuts checked. Oplev servos turned off. Particle count checked. Vertex crane functionality checked.

  10531   Wed Sep 24 11:02:38 2014 manasaUpdateLSCMoving SRM

I looked at the CAD layout and it seems like we will clearly be clipping POY if we move SRM by 7.5cm. Since POY is not visible at low power, we cannot be sure about the clipping.

We should have a plan B before we move everything. I suggest we move a combination of SRM and SR2 to get the desired SRC length.
Moving SR2 will require extra effort to walk the beam unclipped through all the 6 output steering mirrors that follow; but there will be little room for error if we use irides to propagate the beam through the first 4 mirrors that are in the BS and ITMY chamber.

  10532   Wed Sep 24 13:28:48 2014 SteveUpdateVACvent is completed

 The vent is completed. ITMX was kicked up accidentally. Valve configuration: chamber open, RGA is pumped through VM2  Maglev

  10533   Wed Sep 24 16:02:58 2014 JenneUpdateVACvent is completed

[Steve, EricQ, Jenne]

ITMY and BS heavy doors are off, light doors are on.  Q is aligning the IFO.

  10534   Wed Sep 24 18:17:46 2014 ericqUpdateGeneralAlignment Restored

Interferometer alignment is restored

ASS has been run on each arm, recycling mirrors were aligned by overlapping on AS camera. 


Notes:

  • Mode cleaner alignment took some manual tweaking, locked fine around 1k counts. Still no autolocker.
  • At this point, some light was visible on AS and REFL, which was a good sign regarding TTs. 
  • Used green light to align ETMs to support a green 00 mode. 
  • Ensured no recylcying flashes were taking place on AS camera and PRM face camera.
  • Arms were locked using AS55, with the other ITM misalgined, for better SNR than PO[XY]. ASS brought arm powers to ~0.06, which is about what we would expect from 1k MC2 trans instead of 16k.
    • ASS Yarm required debugging, see below.
    • ETMX was getting kicks again. Top Dsub connector on the flange near the ground closer to the end table was a little loose. We should fasten it more securely.
  • At this point, michelson alignment was good. Brought in PRM to see PRC flashes, REFL spot was happy. Brought in SRM to AS sppot. 
  • Saved all optic positions. 
  • Oplevs:
    • PRMs new aligned state is falling off the QPD.
    • ETMs and BS oplev centering are fine, rest are less good, but still on the detector.

 


ASS-RFM issue:

ETMY was not getting its ASC pitch and yaw signals. C1SCY had a red RFM bit (although, it still does now...)

I took a look at the c1rfm simulink diagram and found that C1RFM had an RFM block called C1:RFM-TST_ETMY_[PIT/YAW] and C1SCY had one called C1:TST-SCY_ETMY_[PIT/YAW]. 

It seems that C1TST was illegally being used in a real signal chain, and Jenne's recent work with c1tst broke it. I renamed the channels in C1RFM and C1SCY to C1:RFM-SCY_ETMY_[PIT/YAW], saved, compiled, installed, restarted. All was well.

There are still some  in SCY that have this TST stuff going on, however. They have to do with ALS, it seems, but are SHMEM blocks, not RFM. Namely:

  • C1:TST-SCY_TRY
  • C1:TST-SCY_GLOBALPOS
  • C1:TST-SCY_AMP_CTRL

 

  10535   Wed Sep 24 18:56:45 2014 ericqUpdateGeneralOttavia slowness

Ottavia was having some severe interaction latency today. Xorg was taking up >90% of the CPU, just sitting around. The machine was logged in to a desktop session with lots of graphical effects turned on. I changed the system default session to "gnome-fallback" in /etc/lightdm/lightdm.conf, which was already set as the default for controls, but wouldn't get chosen for the autologin that happens on boot. 

Hopefully this helps ottavia stay usable...

  10536   Thu Sep 25 08:21:15 2014 SteveUpdateVACvent day 1

Quote:

[Steve, EricQ, Jenne]

ITMY and BS heavy doors are off, light doors are on.  Q is aligning the IFO.

 

  10537   Thu Sep 25 10:53:32 2014 SteveUpdateSUSHeNe laser test

 

 

  10538   Thu Sep 25 11:33:41 2014 JenneUpdateLSCPOY alignment laser

Quote:

I looked at the CAD layout and it seems like we will clearly be clipping POY if we move SRM by 7.5cm. Since POY is not visible at low power, we cannot be sure about the clipping.

 I was bad and forgot to elog this yesterday (bad grad student!), but I setup a laser pointer to show us where the POY beam is. 

To do this, I removed the tiny mirror that sends the beam to the POY RF PD (so we do not have POY to lock the Yarm right now.  I think Q has successfully been using AS).  The laser pointer goes through 2 temporary steering mirrors, then passes through the place that the tiny mirror usually sits, and then travels along the POY path into the vacuum system.  The idea here is that we should be able to adjust the laser pointer and the temp steering mirrors, and not touch any of the actual POY mirrors, but still get the green beam to go all the way to ITMY.  Yesterday I confirmed that the laser pointer was hitting the in-vac POY pickoff mirror, and today Q and Manasa are doing final adjustment to get the beam all the way to the ITM. 

  10539   Thu Sep 25 11:38:47 2014 JenneUpdatePEMSeismometers in place

[Zach, Jenne, Steve]

This work happened on Tuesday.  Bad Jenne for forgetting to elog it!

Zach brought the 40m's seismometers back (one Guralp and one T-240).  We have set the seismometers on their slabs.  Also, we ran the T240 cable from 1X5 over to the vertex slab.  Also, also, Zach and Steve mounted the T-240 readout box in the 1X5 rack.  We have not yet hooked it up to power, although there are fused power blocks available on that rack. 

So, the T-240 box needs power, and then we need to connect the seismometers to their respective boxes.  Also, we need to run medium-short BNC cables from the T-240 readout box to the PEM AA board over in 1X7.

  10540   Thu Sep 25 15:41:15 2014 ericqUpdateComputer Scripts / ProgramsRossa having a better day

 

I think I found out why rossa was mad. 

An apt-get update on the 18th downloaded kernel 2.6.32-65-generic, so 2.6.32-58-generic, which what was previously chosen as a working kernel, had moved down in the grub ordering.

It turns out the grub configuration accepts strings, so I changed it to GRUB_DEFAULT="Ubuntu, with Linux 2.6.32-58-generic", ran sudo update-grub, and Rossa now seems to boot happily. 

  10541   Thu Sep 25 19:42:12 2014 ericqUpdateGeneralVent progress

[q, Jenne, Manasa]

ELOG Outline

  • Aligned arms
  • Took a bunch of photos of ITMY chamber. 
  • Used Crystallaser to reverse trace POY beam path
  • Realized real POY flashes were visible
  • Tried adjusted POY steering to give us enough room to move SRM forward 3 in
  • Not enough steering room
  • Placed beam centering targets just before OM3 and after OM4, on far side of BS table
  • Twisted SR2 by ~5 degrees
  • Moved SRM laterally ~3 inches (beam had been hitting optic center, then suspension cage after SR2 twist)
  • Moved SRM foward about 3 inches, adjusted angle for coarse retroreflection
  • Measured distances between suspensions
  • Tried running Gabriele's distance reconstruction code, results not looking so good; redundancy checks are off by ~1cm
  • Started roughly repositioning OM1 and OM2 to get through beam targets
  • Closed light doors
  • ITMY pointing has gone bad, no green or IR resonance to be seen, still have IR and Green in Xarm, so TTs, BS are ok
  10542   Fri Sep 26 09:13:17 2014 SteveUpdateSUSvent day 2

 ITMY in vac table needs leveling.

  10543   Fri Sep 26 11:44:55 2014 nicolasFrogsComputer Scripts / ProgramsLoaded larry's fake filter into C1:ALS-OFFSETTER2

 Larry and Nicolas

Larry's transfer function measurements suddenly started returning 0dB 0degrees when before there was some fake filter in the C1:ALS-OFFSETTER2 filter bank.

We looked in the filter bank and his filter was gone. So I created a new filter called LARRYP in FM2. We also disabled the output so he could drive the filter bank and test his TF code.

  10544   Fri Sep 26 12:25:34 2014 ericqUpdateGeneralVent progress

I figured out that didn't change the initial guess for the fit routine in Gabriele's code. I also changed the fminsearch criteria to least squares fitting, instead of minimax. The consistency checks now look just as good as the previous time we did these kind of measurements, no disagreements bigger than 1.6mm. 

Thus, the current estimate of the SRC length after yesterday's motions is 5402mm, where we desire 5399mm. So, we will try to move SRM 3mm closer to SR2, after confirming that we are not clipping the POY beam. After all that, we will level the table.

  10545   Fri Sep 26 16:10:14 2014 ericqUpdateGeneralVent update

Today so far:

  • I moved SRM forward by 3mm
  • Then I leveled the ITMY table 
  • At this point, bringing the ITMY oplev beam back onto its QPD got me back to green locking and IR flashes 
  • AS and POY beams are both making it out to their tables, as seen by IR card. (Though not to their in-air optics)

Here's my quick brain dump of things to do before we can pump down (anyone see anything missing?):

  • Check the clearance of the POY beam at the SRM cage
  • Re-do distance reconstruction measurements, confirm desired SRC length
  • Lock the SRM cage down fully (right now, has 2 clamps on, and one laying unused)
  • Align SRM for SRC flashes
  • Adjust SRM OSEM positions as needed
  • Adjust SRM oplev beam path, measure lever arm for calibration
  • Confirm beam spots on output mirrors in ITMY and BS chambers are ok
  • Take pictures of ITMY chamber. 
  • Closeup checklist
  10546   Fri Sep 26 17:13:39 2014 ericqUpdateGeneralVent update

Quote:
  • Check the clearance of the POY beam at the SRM cage
  • Re-do distance reconstruction measurements, confirm desired SRC length

POY has >2 inches of clearance from the SRM cage. 

Distance reconstruction indicates an SRC length of 5399mm, which was exactly our target. 

  10547   Mon Sep 29 09:11:25 2014 SteveUpdateVACvent day 5 RGA scan

 

 

  10548   Mon Sep 29 10:29:25 2014 SteveUpdateVACRGA is not running

 

 The RGA time stamp was correct last at 20140527

 

  Rga stopped scanning at 20140530

  10549   Mon Sep 29 12:47:51 2014 ericqUpdateGeneralVent update

Quote:
  •  Lock the SRM cage down fully (right now, has 2 clamps on, and one laying unused)
  • Align SRM for SRC flashes
  • Adjust SRM OSEM positions as needed
  • Adjust SRM oplev beam path, measure lever arm for calibration
  • Confirm beam spots on output mirrors in ITMY and BS chambers are ok

 [Koji, ericq]

We have completed the above points; the ITMY table is still level.

Despite what the wiki says, the SRM LR OSEM open voltage is ~1.97V instead of ~1.64, so we shot for half of that. 

The in-air steering of the SRM oplev return beam needs adjustment. I'll estimate the beam path length when I'm taking pictures and closing up. 

Left to do:

  • Now that AS is back on diode, lock arms and align everything. Confirm everyone's happiness. 
  • Take numerous pictures of ITMY chamber.
  • Center oplevs
  • Put doors on
  • Close shutters
  • Pump down
  • Replace MC refl Y1 with the beamsplitter
  • Turn PSL power back up

Related In-Air work:

  • Fix POY steering
  • Fix SRM oplev return steering
  10550   Mon Sep 29 17:10:51 2014 ericqUpdateGeneralVent update

Everything is aligned, AS and POY make it out of vacuum unclipped, OSEM readings look good.

I set up the SRM oplev, centered all oplevs.

Tomorrow, we just have to take pictures of the ITMY chamber before we put the heavy doors on. 

  10551   Mon Sep 29 18:12:24 2014 ericqUpdateGeneralVent update

I closed the PSL shutter as we didn't want to burn the mirror surface when we are not working.

  10552   Tue Sep 30 11:53:29 2014 ericqUpdateGeneralVent update

 

Photos have been taken of the ITMY chamber, and uploaded to picasa. Here's a slideshow:

  10553   Tue Sep 30 16:18:57 2014 SteveUpdateVACpump down #78 has started

 

Q checked the earth quake stops of SRM and we put the ITMY & BS doors on. 

  10554   Tue Sep 30 17:26:18 2014 ericqUpdateLSCNew AO cable in place

I've installed a new 2pin lemo cable going from the CM servo out to in2 of the MC servo board, and removed the temporary BNC. I used some electrical tape to give the cable some thickness where the lemo head screws on to try to strain relieve the solder joints; hopefully this cable is more robust than the last. 

I put an excitation into the CM board, and saw it come out of MC_F, so I think we're set. 

  10555   Tue Sep 30 18:02:53 2014 SteveUpdateVACpump down #78 stops at 320 Torr

 

We  stopped pumping just short of 3 hours at 320 Torr.  Pumping speed was 2.7 Torr / min with partially closed RV1 and butterfly valve/

RP1&3 roughing pump hose is disconnected. Butterfly valve removed. The vac envelope is closed. 

  10556   Wed Oct 1 10:21:19 2014 SteveUpdateVACpump down #78 stops at 3.5 Torr

Quote:

 

We  stopped pumping just short of 3 hours at 320 Torr.  Pumping speed was 2.7 Torr / min with partially closed RV1 and butterfly valve/

RP1&3 roughing pump hose is disconnected. Butterfly valve removed. The vac envelope is closed. 

 This is our second stop. I will be back this afternoon.     IFO  P1 3.5 Torr

  

  10557   Wed Oct 1 16:26:53 2014 SteveUpdateVACpump down #78 completed

 

 Pump down reached "vacuum normal" state. IFO _P1 pressure 1e-4 torr in 8 hrs actual pumping time

 PSL shutter is opened.

  10558   Wed Oct 1 19:40:46 2014 ericqUpdateLSCArms IR aligned
Summary:
  • Beamsplitter was put into MC refl path.
  • HWP was rotated to maximize power into PMC. 
  • MC autolocker locked, small alignment tweak led to WFS taking over
  • Light present on REFL, AS and POP!
  • After small adjustments to TTs and ETMY, locked Yarm with AS55, ran ASS. 
  • Adjusted AS camera and RFPD alignment for ASS'd AS beam. 
  • Left arm locked on AS55, aligned new POY beam onto POY11. Centered ITMY oplev while I was there. 
  • After adjusting digital POY11 demod angle with an excitation into ETMY, arms were POX/POY locked and ASS'ed.
  • PRM and SRM eyeball aligned

The IFO is ready for 3F DRMI comissioning 

  10559   Thu Oct 2 09:23:23 2014 SteveUpdateVACvent 77

Quote:

 

 Pump down reached "vacuum normal" state. IFO _P1 pressure 1e-4 torr

PSL shutter is opened.

 IFO_P1 pressure 1.6e-5 torr after 6 days at atm

 

PS: PSL sliding door 11 was left open overnight. The PSL particle count will reach room counts in 20 seconds at low speed of HEPA

  10560   Thu Oct 2 14:36:52 2014 steveUpdatePEMoil drops on vertex crane

Quote:

 

 KroneCrane Fred inspected and certified the 3 40m cranes for 2014. The vertex crane crane was load tested at fully extended position.

 Small oil drops were found during prevent inspection of the vertex crane. They were wiped off. It took 231 days to grow this size.

  10561   Thu Oct 2 20:54:45 2014 KojiUpdateIOOIMC WFS measurements

[Eric Koji]

We made sensing matrix measurements for the IMC WFS and the MC2 QPD.

The data is under further analysis but here is some record of the current state to show
IMC Trans RIN and the ASC error signals with/without IMC ASC loops

The measureents were done automatically running DTT. This can be done by

/users/Templates/MC/wfsTFs/run_measurements

The analysis is in preparation so that it provides us a diagnostic report in a PDF file.

  10562   Fri Oct 3 03:02:17 2014 ericqUpdateLSCNo luck locking DRMI

I haven't been able to lock the DRMI tonight, neither with 1F and no arms nor 3F and arms held off with ALS... I tried previous recipes, and new combinations informed by simulations I've run, to no avail. 

I touched the alignment of the green beat PD on the PSL table, since the X beatnote was rather low, but wasn't able to improve it by much. I never took a spectrum, since it wasn't my main focus tonight, but the low frequency motion of both arms on ALS, as observed by RIN, was good as I've ever seen it. 

In our WFS work earlier today, Koji and I reset the WFS offsets, and it actually seems to have helped a good deal, in terms of the "fuzz" of MC REFL on the wall striptool. I had previously presumed this to be due to excess angular motion, but perhaps it is more accurately described as an alignment offset that let the nominal angular motion couple into the RIN more. 

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