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  40m Log, Page 127 of 344  Not logged in ELOG logo
ID Date Author Typeup Category Subject
  4050   Tue Dec 14 01:04:23 2010 kiwamuUpdateSUSalignment of ITMs and PRM done

   The alignment of the ITMs and the PRM has been done.

 As a result their reflections now come out at the REFL port successfully. 

The vacuum work is going on well as we scheduled at the last meeting.

 

(plan for tomorrow) 

 - installation of ETMY

 - installation of OSEMs on ETMY

 - alignment of the beam to the center of ETMY

 - alignment of the ETMY to the beam

 - final alignment of IP_ANG

 - setting up the oplev for ETMY

 - replace one of the steering mirrors at the RFEL path by a 0 deg mirror (see here).

 - setting up POX/POY (if there are time)

 

(today's activity) 

 - aligned the PRM tower such that the reflected beam goes back to exactly the same path as that of the incoming beam.

 - leveled the ITMY table because the OSEMs of ITMY had been completely out of range.

 - aligned the ITMY and ITMX in order to let the reflections back to REFL.

 - with a help from Osamu, we put a CCD camera, which actually had been used as OMC_T, just after the view port on the AP table.

 - looking at the CCD monitor we were able to see the reflected lights from the ITMs. (In fact sensor cards didn't help looking for the lights.)

  - playing with the alignment of the ITMs, we easily obtained Michelson fringes, which were also visible on the CCD monitor.

  4051   Tue Dec 14 04:14:53 2010 ranaUpdateElectronicsRF Photodiode Characterizations

This is looking better, but the fit data for the TF should be plotted along with the data. The data should be made up of points and the fit a line.

For the fit, we should have the Q of the main resonance as well as the peak height of the main resonance and the values of the gain at the notch frequencies.

Also the peak as well as the notches should have the frequencies fit for and labeled. In principle, you can make the plot on the wiki have all of the data. Then in the end we can print the plot in a small size and glue it to the PD's backside.

  4052   Tue Dec 14 09:26:17 2010 ZachUpdateelogrestarted

 Restarted the elog with the script

  4053   Tue Dec 14 11:24:35 2010 josephbUpdateCDSburt restore

I had updated the individual start scripts, but forgotten to update the rc.local file on the front ends to handle burt restores on reboot.

I went to the fb machine and into /diskless/root/etc/ and modified the rc.local file there.

Basically in the loop over systems, I added the following line:

/opt/epics-3.14.9-linux/base/bin/linux-x86/burtwb -f /opt/rtcds/caltech/c1/burt/autoburt/latest/${i}epics.snap  -l /opt/rtcds/caltech/c1/burt/autoburt/logs/${i}epics.log.restore -v

The ${i} gets replaced with the system name in the loop (c1sus, c1mcs, c1rms, etc)

  4054   Tue Dec 14 15:15:19 2010 kiwamuUpdateSUSput ETMY and aligned the beam

  [Zach and Kiwamu]

 We installed the new ETMY tower and successfully aligned the beam to the center of ETMY.

 Also we finished the final alignment of IP_ANG.

 

 

(what we did)

 - took the old ETM out  from the chamber and put it on the flow bench at the X end.

 - with a help from Joe and Osamu, we brought the new ETM and put it roughly on place.

 - did a fine positioning of ETMY.

 - covered the ETM tower with a large peace of aluminum foil in order to see the spot on a video monitor.

 - stoled a compact video monitor that was sitting on the PSL table since we don't have any monitors at the Y end.

 - made a ~1cm hole on the foil as a target for the beam.

 - steered PZT1 in order to correct the beam position on ETMY. This is done by looking at the spot on the video monitor.

 - steered IPANG_SM1 to let the beam hit a steering mirror in the ETMY chamber which Koji installed recently.

     Now we have IP_ANG coming out from the viewport of the ETMY chamber.

  4055   Tue Dec 14 22:42:56 2010 kiwamuUpdateSUSinstalled the last TT . And some more progresses

  [Koji, Oasmu and Kiwamu]

We made the following progresses :

   (1) installation of the last TT called SR2.

 (2) fixing an earthquake stop issue on the BS

  (3) fixing a clipping of beams at the dark port


(earthquake stops on the BS)

 - When we were aligning the BS, we found that the BS showed funny behaviors.

For example a kick on LR didn't shake LRSEN, and a big DC angular offset (~ 8 in the medm screen ) was needed to keep a horizontal beam axis in the reflection.

We checked all the earthquake stops and found two suspicious earthquake stops at right bottom side.

They looked like slightly touching the BS. So we moved them further away from the BS.

Then the problem had gone.  We doublechecked the health by kicking, applying an angular offset  and so on.

 

(beam clipping)

We found transmitted/reflected beams from the BS to the dark port was clipped at the BS tower.

We moved the BS tower by ~1cm and realigned the rotation of the BS tower.

We also found the beam spots on the two TTs, PR2 and PR3, were offcentered. Especially the beam spot on PR3 was almost on the edge of the mirror.

Probably this was because we touched PZT1 when aligning the beam to the Y end.

So it means, it is not a good idea to align the beam to the end only by steering PZT1. We should use PR2 and PR3 as well when we align the beam to the Y end.

We realigned them such that the beam hits the center of PR2, PR3 and ETMY.

  4057   Wed Dec 15 13:36:44 2010 josephbUpdateCDSETMY IO chassis update

I gave Alex a sob story over lunch about having to go and try to resurrect dead VME crates.  He and Rolf then took pity on me and handed me their last host interface board from their test stand, although I was warned by Rolf that this one (the latest generation board from One Stop) seems to be flakier than previous versions, and may require reboots if it starts in a bad state.

Anyways, with this in hand I'm hoping to get c1iscey damping by tomorrow at the latest.

  4058   Wed Dec 15 14:23:32 2010 KojiUpdateCDSETMY IO chassis update

Great!

I wish this board works fine at least for several days...

Quote:

I gave Alex a sob story over lunch about having to go and try to resurrect dead VME crates.  He and Rolf then took pity on me and handed me their last host interface board from their test stand, although I was warned by Rolf that this one (the latest generation board from One Stop) seems to be flakier than previous versions, and may require reboots if it starts in a bad state.

Anyways, with this in hand I'm hoping to get c1iscey damping by tomorrow at the latest.

 

  4060   Wed Dec 15 17:21:20 2010 josephbUpdateCDSETMY controls status

Status:

The c1iscey was converted over to be a diskless Gentoo machine like the other front ends, following the instructions found here.  Its front end model, c1scy was copied and approriately changed from the c1scx model, along with the filter banks.  A new IOP c1x05 was created and assigned to c1iscey.

The c1iscey IO chassis had the small 4 PCI slot board removed and a large 17 PCI slot board put in.  It was repopulated with an ADC/DAC/BO and RFM card.  The host interface board from Rolf was also put in. 

On start up, the IOP process did not see or recognize any of the cards in the IO chassis.

Four reboots later, the IOP code had seen the ADC/DAC/BO/RFM card once.  And on that reboot, there was a time out on the ADC which caused the IOP code to exit.

In addition to the not seeing the PCI cards most of the time, several cables still need to be put together for plugging into the the adapter boards and a box need to be made for the DAC adapter electronics.

 

  4061   Wed Dec 15 18:29:59 2010 JenneUpdatePEMSeismometer Channels Being Recorded Again

The Seismometer channels are once more being recorded.  Alastair brought Gur1 back from the ATF the other day, and today I put it in its place below MC2 (yeah, the numbers are backwards.  But they always have been.) 

I checked the matching between BNC inputs on the breakout box to the ADC channels as labeled in the SimuLink diagram.  To do this I had all 32 channels activated, and I put a 1Hz, 1Vpp sine wave into various BNC inputs to see what channel they showed up as.  At first things were a bit backwards (BNC channels 1-16 going to ADCs 16-31, and BNCs 17-32 going to ADCs 0-15), but then Joe quickly flipped the cables on the adapter board in the back and things are in the correct order now.  Channel 1 on the BNC board corresponds to channel 0 on the ADC, etc. 

I checked that jumping near each seismometer made the signals spike, which they did. 

I then changed the channel names in the c1pem.mdl SimuLink diagram to match the old channel names for the Guralps and the accelerometers, and deleted all of the other channels that aren't being used.  There's a table in the diagram to indicate what goes with what, as of today.  If you do anything to the PEM diagram, please update the table so it's easy to look things up.

I recompiled the code, but have not yet restarted the frame builder since Zach and Kiwamu are working on some things in the chamber, and I don't want to be annoying (so the channels aren't actually being recorded quite yet). 

Edit, 7:15pm:  Just kidding.  Something didn't work, and I have to track down what.  I'm not getting any data yet.

  4062   Wed Dec 15 23:10:40 2010 KojiUpdateIOOSRM Oplev / Dark Steering mirrors installed

I helped the vacuum installation work in the evening.

- Three steering mirrors after the SRM (OM1-OM3) were installed on the table. OM1 and OM2 were aligned.
  OM3 is in-place but not aligned to the OM4 (PZT).

- The ITMY oplev setup was disintegrated. The SRM/ITMY oplev beams were prepared.

- The SRM oplev mirrors were placed on the table and aligned.

- The ITMY oplev mirrors were placed on the table but not in-place.

  4063   Thu Dec 16 01:23:43 2010 kiwamuUpdateSUSSRM OSEMs installed

  [Zach and Kiwamu]

 We worked on some more vacuum businesses.  Today we finished did the following works:

 - alignment of the POX mirrors 

 - alignment of the POP1 and POP2 mirrors

 - installation of OSEMs onto SRM

 - alignment of the SRM tower

 

 (alignment of POP mirrors)

 Since a beam on the POP path was quite too weak to see even by IR viewers, we used a He-Ne laser to imitate the real beam instead.

We injected the He-Ne beam from an optical bench to the chamber, and made it go through the PRM and PR2 by using some steering mirrors.

 

(OSEM cables)

 The pin assignment was flipped in a way of mirror image due to the extension cables which cause a mirroring.

 So we made mirroring connectors to flipp them back to the correct pin assignment, and plugged the mirroring connectors in between the feedthrough of the BS chamber and the SRM satellite box.

This is a picture showing how they are connected now.

DSC_2757_ss.jpg

  4064   Thu Dec 16 10:52:42 2010 josephbUpdateCamerasNew PoE digital cameras

We have two new Basler acA640-100gm cameras.  These are power over ethernet (PoE) and very tiny.

  4065   Thu Dec 16 15:10:18 2010 josephb, kiwamuUpdateCDSETMY working at the expense of ETMX

I acquired a second full pair of Host interface board cards (one for the computer and one for the chassis) from Rolf (again, 2nd generation - the bad kind).

However, they exhibited the same symptoms as the first one that I was given. 

Rolf gave a few more suggestions on getting it to work.  Pull the power plugs.  If its got slow flashing green lights, just soft cycle, don't power cycle.  Alex suggested turning the IO chassis on before the computer.

None of it seemed to help in getting the computer talking to the IO chassis.

 

I finally decided to simply take the ETMX IO chassis and place it at the Y end.  So for the moment, ETMY is working, while ETMX is temporarily out of commission. 

We also made the necessary cables (2x 37 d-sub female to 40 pin female and 40 pin female to 40 pin female) .  Kiwamu also did nice work on creating a DAC adapter box, since Jay had given me a spare board, but nothing to put it in.

  4066   Fri Dec 17 00:30:05 2010 KojiUpdateIOOITMY / SRM / BS / PRM OPLEVs aligned

[Steve and Koji]

The invac OPLEV mirrros were aligned before we get to the PMA party.

The OPLEV mirrors were adjusted in accordance with the optical layout.
Surprisingly the optical layout was enough precise such that we have the healthy red beams on the optical tables.
Steve placed the apertures at the position of the returning spots while I shook the stack to check if the range of the spot motion is sufficient.

The sole thing that has been deviated from the optical layout was that the SRM returning beam had to be reroute
as the SRM has better reflectivity on the AR surface in stead of the HR one.

  4067   Fri Dec 17 00:55:30 2010 KojiUpdateIOOThe dark port beams reached the AP table

[Koji and Kiwamu]

We obtained two dark port beams on the AP table: OMC REFL and AS

- First, IPANG and BS were aligned so as to have the beams on the center of the ETMs.

- Then ITMX/ITMY/PRM/SRM were aligned to have fringes in a single spot anywhere.

- As we already had the dark port beam on the steering mirrors on the BS table, today the PZT mirrors were adjusted.
This work was the beam steering between the BS table to the OMC table. After some tweaking of the mirror mounts, 
the spot on the last PZT mirror was found.

As we have not touched any of the OMC optics since they were aligned well, the alignment has been adjusted by the nobs of the PZT steering mirrors.
Once the beam is on the output mode matching telescope (OMMT), the work was quite easy thanks to the beam shrinking by the OMMT.

Note that the dark port beam is slightly clipped by the green steering mirror. The steering mirror will be moved next time.

After the alignment, we indeed obtained OMC REFL and AS beams on the AP table.
The fringes were visible on the OMC REFL CCD.

We keep the dark port setup on the OMC (in-vac) and AP tables so that they can be the reference of the dark port alignment.
In principle we can align the beams onto the OMC by the two PZT mirrors.


What is left?

Our minimum success of this vent is to setup the X arm cavity which is needed for the green locking.
This setup was already realized. So we fulfilled the condition to close the tank even if the damping of
the ETMY is not achieved. (But we should try)

Tomorrow, we make a light touches to POY, Green, IPPOS, and check the table leveling, clamping, etc, in general.

JD:  We should check OSEMs for all optics *after* table leveling.  Some of them (esp. BS and ITMX) are currently close to their limits right now.

KA: Check green alignment. / Take photos of the tables. / Fix the leveling weights


Location    Optics            Action
--------------------------------------------------------------
@ITMY -     POY               mirror replacement (45deg->0deg) / alignment

@BSC -      Green steering    alignment
            IPPOS steering    alignment
            Beam dumps
            Table Leveling

@ETMX -     Al foil removal
            Table Leveling

@ETMY -     ETMY damping
            OSEM
            OPLEV
            Table Leveling

@ITM/ETM -  Mirror Wiping

  4068   Fri Dec 17 02:22:06 2010 kiwamuUpdateCDSETMY damping: not good

  I made some efforts in order to damp ETMY, however it still doesn't happily work.

 It looks like something wrong is going on around the whitening filters and the AA filter borad.

I will briefly check those analog parts tomorrow morning.

 

- - -(symptom)

Signs of the UL and the SD readouts are flipped, which I don't know why.

At the testpoints on the analog PD interface board, all the signs are the same. This is good.

But after the signals go through the whitening filters and AA filters, UL and SD become sign-flipped.

I tried compensating the sign-flips by changing the sign by means of the software, but it didn't help the damping. 

In fact the suspension got crazy when I activated the damping. So I have no idea if we are looking at exactly right readouts or some sort of different signals.

 

- - -(fixing DAC connector)

 I fixed a connector of the DAC ribbon cable since the solderless connector was loosely locked to its cable.

Before fixing this connector I couldn't apply voltages on some of the coils  but now it is working well.

  4069   Fri Dec 17 03:37:47 2010 ranaUpdateSUSITMY / SRM / BS / PRM OPLEVs aligned

Quote:

The sole thing that has been deviated from the optical layout was that the SRM returning beam had to be reroute
as the SRM has better reflectivity on the AR surface in stead of the HR one.

 I suppose that if we were really clever we would intentionally choose either the AR or HR surface so as to minimize the effect of the thermal lensing and/or thermal expansion from the locked interferometer absorption.

  4070   Sat Dec 18 01:17:04 2010 kiwamuUpdateIOOsome more alignments

 [Koji and Kiwamu]

 We did some more vacuum works today. It is getting ready to pump down.

 (what we did) 

 - alignment of the POY mirrors. Now the beam is coming out from the ITMY chamber successfully

  - leveling of the tables (except for the IOO and OMC chamber)

  - realigned the beam axis down to the Y arm because the leveling of the BS table changed the alignments.

 - installed IP_POS mirrors

 - aligned the green beam and made it overlap with IR beam path.

 - repositioned green steering mirrors since one of them are too close to the dark beam path

 - aligned everything.

  4071   Sat Dec 18 06:24:49 2010 ranaUpdateelogrestarted

The process was taking up 100% of the CPU and not responding via web. The .log file showed the last action was somebody reading/editing one of Jenne's entries from August regarding TT ECD. The restart script didn't work, so I had to do a 'kill -9' to get it to die.

  4072   Sat Dec 18 23:33:06 2010 KojiUpdateelogrestarted

Did the same.

Quote:

The process was taking up 100% of the CPU and not responding via web. The .log file showed the last action was somebody reading/editing one of Jenne's entries from August regarding TT ECD. The restart script didn't work, so I had to do a 'kill -9' to get it to die.

 

  4073   Sun Dec 19 11:19:42 2010 KojiUpdateelogrestarted

Did it again. It seemed that Google bot came to the elog and tried to obtain "http://nodus.ligo.caltech.edu:8080/robots.txt". That was the last of the log.
Bot came from the AJW's homepage. Also Google FeedFecther came to the elog.

  4074   Sun Dec 19 22:45:28 2010 ranaUpdateelogrestarted

I deleted the yellow box which showed up by default when making an elog entry. Would be nice if we could make it so that you have to click a button to 'opt-in' for the yellow box rather than get it by default.

I added a 'robots.txt' file to the /users/public_html/ area using Google's instructions (it only works with robot compliant crawlers), but am not sure how to put robots.txt into the elog port.

  4075   Mon Dec 20 10:06:36 2010 kiwamuUpdateCDSETMY damped

  Last Saturday I succeeded in damping the ETMY suspension eventually.

This means now ALL the suspensions are happily damped. 

It looked like some combination of gains and control filters had made unstabie conditions.

 2010Dec18.png

  I actually was playing with the on/off switches of the control filters and the gain values just for fun.

Then finally I found it worked when the chebyshev filters were off. This is the same situation as Yuta told me about two months before.

Other things like the input and the output matrix looked nothing is wrong, except for the sign flips at ULSEN and SDSEN as I mentioned in the last entry (see here).

So we still should take a look at the analog filters in order to make sure why the signs are flipped.

  4076   Mon Dec 20 10:47:29 2010 KojiUpdateIOOPlan for closing the vacuum chambers

Monday

  • Place the bars on the in-vac tables to mark the positions of the test mass suspensions. (ITMX/ITMY/ETMX/ETMY)
  • Check the table leveling again (ITMX/ITMY/ETMX/ETMY/BSC)
  • Align the whole interferometer.
  • Check the OPLEV spots by either QPDs or apertures
  • Check the OSEM values (MC1/2/3, BS, PRM, SRM, ITMX, ITMY, ETMX, ETMY)
  • Energize OMC PZTs.
    • We have removed the cards at the back of the HV driver.
    • Insert the card and check the connection.
    • Adjust the DC values at the middle of the range.
      -> They have an internal bias circuit to provide +75V at the outputs. (D060287).
      The actual voltages confirmed.
    • Adjust the physical knobs of the PZTs such that we can see the spots at the OMCR cam
  • If everything is fine, attach the access connector.
  • If still everythig is fine, put the BS heavy door.

Tuesday

- Do the following list for all of the testmass chambers.

  • Check if the OSEMs and the OPLEV are still fine.
  • Inspect the surface of the mirror with a laser pointer or a fiber coupled halogen light.
  • Blow the mirrors by the ionization gun.
  • Inspect the mirror surface again.
  • Move the suspension tower close to the door.
  • Make a single drag-wipe with iso
  • Move the SOS tower at the original place.
  • Check the OSEMs and the OPLEVs. Adjust the alignment.
  • Put the heavy door.

- Start slow pumping

  4077   Mon Dec 20 16:57:58 2010 steveUpdateIOOchecking out & closing the vacuum chambers
  • Check EQ-stops
  • clamp down counter weights
  • check other components are clamped
  • remove all tools
  • check cabling is not is not shorting out seismic stack or blocking beam
  • confirm well centered spots on mirrors
  4078   Mon Dec 20 22:56:20 2010 JenneUpdateIOOPlan for closing the vacuum chambers

Tuesday

  • If still everythig is fine, put the BS heavy door.

- Do the following list for all of the testmass chambers.

  • Check if the OSEMs and the OPLEV are still fine. (ITMX and ITMY were not done on Monday, so need extra care.)
  • Inspect the surface of the mirror with a laser pointer or a fiber coupled halogen light.
  • Blow the mirrors by the ionization gun.
  • Inspect the mirror surface again.
  • Move the suspension tower close to the door.
  • Make a single drag-wipe with iso
  • Move the SOS tower at the original place.
  • Check the OSEMs and the OPLEVs. Adjust the alignment.
  • Put the heavy door.

- Start slow pumping

  4079   Mon Dec 20 23:10:25 2010 JenneUpdateSUSPretty much ready for pump-down. A few final things....

[Kiwamu, Jenne, Koji, Osamu]

We have mostly prepared the IFO for pump down. 

After lunch [Steve, Bob, Koji, Kiwamu, Jenne, Joe, Joon Ho, Vladimir, Osamu] put the access connector back in place.  Hooray!  Steve still has to check the Jam Nuts before we pump down.  Kiwamu checked the leveling of the IOO table, and fixed all of the weights to the table.

For all 4 test masses, bars (upside-down dog clamps) were placed to mark the alignment of 2 sides of the suspension tower.  All test mass tables were re-leveled, and the weights fixed to the tables.  

For ETMY, PRM, BS, SRM, we confirmed that the OSEMs were close to their half-range.  ETMX was already fine.  ITMY (the screens and the optics wiki are still old-convention, so this is listed as ITMX! No good!) OSEMs are pretty much fine, but ITMX desperately needs to be adjusted.  Unfortunately, no one can find the standard screwdriver (looks like a minus), to adjust the ITM OSEMs.  All the other towers had hex-key set screws, but the ITMs need a screwdriver.  We will ask Bob to sonicate a screwdriver in the morning. 

 

 

  4080   Mon Dec 20 23:32:58 2010 kiwamuUpdateIOORe:checking out & closing the vacuum chambers

  4081   Tue Dec 21 08:26:08 2010 ranaUpdateelogelogd is getting killed by Suresh

Suresh killed the elogd again from India. This was the log file:

Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Referer: http://www.ligo.caltech.edu/~ajw/40m_upgrade.html
Cookie: elmode=threaded; __utma=65601905.411937803.1291369887.1291369887.1291369887.1; __utmz=65601905.1291369887.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); SITESERVER=ID=4981c5fd42ae53c9c9e0980f2072be4f
Via: 1.1 sfire5.du.ac.in:3128 (squid/2.6.STABLE6)
X-Forwarded-For: 10.11.1.120
Cache-Control: max-age=259200
Connection: keep-alive

Stop killing our elog!

  4082   Tue Dec 21 11:52:58 2010 josephbUpdateComputersRGA scripts fixed, c0rga fixed

c0rga apparently had a full hard drive.  There was 1 Gig log file in /var/log directory, called Xorg.0.log.old which I deleted which freed up about 20% of the hard drive.  This let me then modify the crontab file (which previously had been complaining about no room on disk to make edits).

I updated the crontab to look at the new scripts location, updated the RGA script itself to write to the new log location, and then created a soft link in the /opt directory to /cvs/cds/rtcds on c0rga.

The RGA script should now be running again once a day.

  4085   Wed Dec 22 06:50:19 2010 ranaUpdateelogelogd is getting killed by Suresh

After another elog crash, I've blacklisted the domain that Suresh is using by editing the apache httpd.conf. Let's see what happens now.

  4086   Wed Dec 22 11:24:23 2010 haixingUpdateSUSmeasurement of imbalance in quadrant maglev protope

Yesterday, a sequence of force and gain measurement was made to determine the imbalance in the

quadrant, magnetic-levitation prototype. This was the reason why it failed to achieve a stable levitation.

The configuration is shown schematically by the figure below:

 

config_2x2.png

 

Specifically, the following measurements have been made:

(1) DC force measurement among four pairs of magnets at fixed distance with current of the coils on and off

From this measurement,  the DC force between pair of magnets is determined and is around 1.6 N at with a

separation of 1 cm. This measurement also lets us know the gain from voltage to force near the working point.

 

The force between pair "2" is about 13% stronger than other pairs which are nearly identical. The force by the

coil is around 0.017 N per Volt (levitation of 5 g per 3 Volt); therefore, we need around 12 volt DC compensation

of pair "2" in order to counterbalance such an imbalance.  Given the resistence of the coil equal to 26 Om, this

requires almost 500 mA DC compensation. Koji suggested that we need a high-current buffer, instead of what

has been used now.

 

(2) DC force measurement among four pairs of magnets (with current of the coils off) as a function of distance

From this measurement, we can determine the stiffness of the system. In this case, the stiffness or the

effective spring constant is negative, and we need to compensate it by using a feedback control. This is

one of the most important parameters for designing the feedback control. The data is still in processing.

 

(3) Gain measurement of the OSEM from the displacement to voltage.

This measurement is a little bit tricky due to the difficulty to determine the displacement of the flag.

After several measurements, it gave approximately 2 V/cm.

 

Plan for the next few days:

From the those measurements, all the parameters for the plant and sensor that need to determine the

feedback control are known. They should be plugged into the simulink model and to see whether the

old design is appropriate or not. Concerning the experimental part, we will first try to levitate the configuration

with 2 pairs of magnets, instead of 4 pairs, as the first step, which is easier to control but still interesting.

 

 

 

 

 

 

  4087   Wed Dec 22 15:30:47 2010 OsamuUpdateASCETMY oplev fixed

According to c1scy.mdl, OL signals should be connected to adc_0_24 to adc_0_27 but they were connected to adc_0_16 to adc_0_19 which are assigned to QPD signals.

Actually cable connections were messed up. One ribbon cable was connected from QPD driver and ADC ports assigned for OL, and another ribbon cable was connected from the board combining the signals of oplev and QPD to ADC port assigned for QPD.

Now ETMY oplev is working well and aligned to center.

  4088   Wed Dec 22 15:47:22 2010 KojiUpdateVACTank closing procedure

[Jenne Kiwamu Joe Osamu Steve Koji]

Yesterday (21st), we closed the BSC and the four testmass chambers.

We splitted the team into three.

- Wiping team (Jenne/Kiwamu)
- Suspension team (Osamu/Koji)
- Door closing team (Joe/Steve)

While the wiping team was working, the suspension team prepared the next suspension.
Once the mirror was wiped, the suspension team restored that suspension at the position of the markings on the table.

After the wipe of the first mirror, the wiping team got experienced and they were the fastest among the teams.
So the wiping team worked as the second suspension team when necessary.

All of us became the closing team after the last suspension has been restored.

We checked that we still have the Michelson fringes and the oplev pointings.

In total, the work was very efficient such that we only took four hours for the entire process.

We left the suspension marking on the optical tables because they are quite useful.

  4091   Thu Dec 23 03:15:11 2010 KojiUpdateelogelogd is getting killed by Suresh

ELOG has crashed and I restarted it.

Actually the filtering is not effective so far as elog is not using apache but has its own web server inside.
So this just block the access to port 30889 (=SVN, Dokuwiki, etc).

Quote:

After another elog crash, I've blacklisted the domain that Suresh is using by editing the apache httpd.conf. Let's see what happens now.

 

  4092   Thu Dec 23 08:54:32 2010 SureshUpdateelogthe delhi univ syndrome

Sorry folks!  I couldnt get to the elog and didnt know that the elog was crashing every time I tried to access it. 

But have found other means to access it and the elog is safe for now!

  4093   Thu Dec 23 12:19:43 2010 kiwamuUpdateGreen Lockinginstalled doubling oven base at PSL table

I gave a christmas present to a doubling oven who has been sitting on the PSL table.

The below is a picture of the present I gave. It's a base plate for the doubling oven, made from a block of aluminum, and black-anodized.

The size and the shape are nicely tailored for the combination of the Newfocus kinematic mount and the Covesion oven.

The design had been done by using Solid Works 2010

 

DSC_2820_ss.jpg

 

Here is a picture before he got the present.

DSC_2814_ss.jpg

 

Now he looks pretty happy.

DSC_2815_ss.jpg

  4095   Thu Dec 23 18:51:37 2010 ranaUpdateGreen Lockinginstalled doubling oven base at PSL table

This is not such a bad base design, but remember that we have to get a couple of parts with the purple anodize to see if there is a difference between black and purple in terms of the 532 nm reflectivity.

  4096   Thu Dec 23 22:13:50 2010 KojiUpdateGeneralPZT HV turned on

The four IOO PZTs have been turned on in order to confirm the alignment of the IFO.

Once they are turned on, the spots (ITMX/ITMY/PRM/SRM) on the REFL CCD have been easily found.

When the X-arm was aligned to the green beam, it is easily locked to TEM00. Also some LG modes were visible.
i.e. There is some room to improve the mode matching.
The transmitted green at the PSL table is a bit too high and clipped by the first mirror on the table.

No IR flashes were found in either arms.

------------------

The below are the range and the set values of the strain gauge readback for the PZTs.
When the closed loop buttons are activated the PZTs are fixed at those values, if no one touches the set point dials.

            Min   Max   SetP | Display on the module
PZT1 Yaw    2.20  9.95  6.08 | Broken
PZT1 Pitch -0.011 8.89  4.40 | 1.58

PZT2 Yaw    0.737 9.94  5.37 | 2.17
PZT2 Pitch  0.010 9.42  4.71 | 1.89

  4097   Fri Dec 24 09:01:33 2010 josephbUpdateCDSBorrowed ADC

Osamu has borrowed an ADC card from the LSC IO chassis (which currently has a flaky generation 2 Host interface board).  He has used it to get his temporary Dell test stand running daqd successfully as of yesterday.

This is mostly a note to myself so I remember this in the new year, assuming Osamu hasn't replaced the evidence by January 7th.

  4099   Fri Dec 31 12:41:02 2010 ranaUpdateGeneralIR flashes

I came in today to check up on the StripTool and burn the Ubuntu LTS (new CDS OS) DVD. I was pretty excited to see the PRM flashes on Mon1.

I waggled the PRM/BS alignments and got a good contrast MICH and then bright flashes in the PRM that totally overload Mon1's CCD.

Now I can see flashes of some IR junk in the X Arm; its way off on the left edge of the mirror, but there's a beam.

For the short term, we can hook up the IO PZTs to some old EPICS channels (like one of the AUX guys in the LSC area), but eventually it has to get hooked up to the new ASC or ASS. We have to bug Joe to see where this shows up in his master diagram.

**Note: if you get lost sometimes when doing the alignments, remember that you can use time_machine_conlog.

Ex:

rossa:general>./time_machine_conlog 2010/12/31,11:00:00 PDT C1:SUS-ITMX_PIT_COMM
Issuing the conlog command:
/cvs/cds/caltech/conlog/bin/conlog +epics -interp at 2010/12/31,11:00:00 PDT "C1:SUS-ITMX_PIT_COMM"


Conlog Replied:

LIGO controls: values at 2010 12/31 11:00:00 pst
 __Epics_Channel_Name______   __value_____
 C1:SUS-ITMX_PIT_COMM         0.406100



Restoring now...

Restoration Successful

Attached is the last 8 days of Vacuum Pressure trend which includes the pumpdown.

  4101   Sat Jan 1 19:13:40 2011 ranaUpdateCDSc1pem now recording data

 I found that there was no PEM data nor any other data (no SUS or otherwise. No testpoints, no DAQ).

I went through the procedure that Jenne has detailed in the Wiki but it didn't work.

1) Firstly, the 'telnet fb 8088' step doesn't work. It says "Connected to fb.martian" but then just hangs. To replicate the effect of this step I tried ssh'ing to fb and doing a 'pkill daqd'. That works to restart the daqd process.

2) The wiki instructions had a problem. In the GUI step, it should say 'Save' after the Acquire bit has been set to 1. Even so, this works to get the .ini file right and the DTT can see the correct channel list, but none of the channels are available. There are just 'Unable to obtain measurement data'.

3) I tried running 'startc1pem', but no luck. I also tried rebooting c1sus from the command line. That worked so far as to come back up with all the right processes running, but still no data. The actual /frames directory shows that there are frames, but we just can't see the data. I also tried to get data usind the DTT-NDS2 method, but still no luck. (*** ITMX and ITMY both came back with all their filters off; worth checking if their BURTs are working correctly.)

Using DataViewer, however, I AM able to see the data (although the channel name is RED). In fact, I am able to see the trend data ever since I changed the Acquire bit to 1. Plot attached as evidence. Why does DTT not work anymore???

  4103   Tue Jan 4 02:58:53 2011 JenneUpdateIOOPower into Mode Cleaner increased

What was the point:

I twiddled with several different things this evening to increase the power into the Mode Cleaner.  The goal was to have enough power to be able to see the arm cavity flashes on the CCD cameras, since it's going to be a total pain to lock the IFO if we can't see what the mode structure looks like.

Summed-up list of what I did:

* Found the MC nicely aligned.  Did not ever adjust the MC suspensions.

* Optimized MC Refl DC, using the old "DMM hooked up to DC out" method.

* Removed the temporary BS1-1064-33-1025-45S that was in the MC refl path, and replaced it with the old BS1-1064-IF-2037-C-45S that used to be there.  This undoes the temporary change from elog 3878.  Note however, that Yuta's elog 3892 says that the original mirror was a 1%, not 10% as the sticker indicates. The temporary mirror was in place to get enough light to MC Refl while the laser power was low, but now we don't want to fry the PD.

* Noticed that the MCWFS path is totally wrong.  Someone (Yuta?) wanted to use the MCWFS as a reference, but the steering mirror in front of WFS1 was switched out, and now no beam goes to WFS2 (it's blocked by part of the mount of the new mirror). I have not yet fixed this, since I wasn't using the WFS tonight, and had other things to get done.  We will need to fix this.

* Realigned the MC Refl path to optimize MC Refl again, with the new mirror.

* Replaced the last steering mirror on the PSL table before the beam goes into the chamber from a BS1-1064-33-1025-45S to a Y1-45S.  I would have liked a Y1-0deg mirror, since the angle is closer to 0 than 45, but I couldn't find one.  According to Mott's elog 2392 the CVI Y1-45S is pretty much equally good all the way down to 0deg, so I went with it.  This undoes the change of keeping the laser power in the chambers to a nice safe ~50mW max while we were at atmosphere.

* Put the HWP in front of the laser back to 267deg, from its temporary place of 240deg.  The rotation was to keep the laser power down while we were at atmosphere.  I put the HWP back to the place that Kevin had determined was best in his elog 3818.

* Tried to quickly align the Xarm by touching the BS, ITMX and ETMX.  I might be seeing IR flashes (I blocked the green beam on the ETMX table so I wouldn't be confused.  I unblocked it before finishing for the night) on the CCD for the Xarm, but that might also be wishful thinking.  There's definitely something lighting up / flashing in the ~center of ETMX on the camera, but I can't decide if it's scatter off of a part of the suspension tower, or if it's really the resonance.  Note to self:  Rana reminds me that the ITM should be misaligned while using BS to get beam on ETM, and then using ETM to get beam on ITM.  Only then should I have realigned the ITM.  I had the ITM aligned (just left where it had been) the whole time, so I was making my life way harder than it should have been.  I'll work on it again more today (Tuesday). 

What happened in the end:

The MC Trans signal on the MC Lock screen went up by almost an order of magnitude (from ~3500 to ~32,000).  When the count was near ~20,000 I could barely see the spot on a card, so I'm not worried about the QPD.  I do wonder, however, if we are saturating the ADC. Suresh changed the transimpedance of the MC Trans QPD a while ago (Suresh's elog 3882), and maybe that was a bad idea? 

Xarm not yet locked. 

Can't really see flashes on the Test Mass cameras. 

  4104   Tue Jan 4 11:06:32 2011 KojiUpdateIOOPower into Mode Cleaner increased

- Previously MC TRANS was 9000~10000 when the alignment was good. This means that the MC TRANS PD is saturated if the full power is given.
==> Transimpedance must be changed again.

- Y1-45S has 4% of transmission. Definitively we like to use Y1-0 or anything else. There must be the replaced mirror.
I think Suresh replaced it. So he must remember wher it is.

- We must confirm the beam pointing on the MC mirrors with A2L.

- We must check the MCWFS path alignment and configuration.

- We should take the picture of the new PSL setup in order to update the photo on wiki.

Quote:

What was the point:

I twiddled with several different things this evening to increase the power into the Mode Cleaner.  The goal was to have enough power to be able to see the arm cavity flashes on the CCD cameras, since it's going to be a total pain to lock the IFO if we can't see what the mode structure looks like.

Summed-up list of what I did:

* Found the MC nicely aligned.  Did not ever adjust the MC suspensions.

* Optimized MC Refl DC, using the old "DMM hooked up to DC out" method.

* Removed the temporary BS1-1064-33-1025-45S that was in the MC refl path, and replaced it with the old BS1-1064-IF-2037-C-45S that used to be there.  This undoes the temporary change from elog 3878.  Note however, that Yuta's elog 3892 says that the original mirror was a 1%, not 10% as the sticker indicates. The temporary mirror was in place to get enough light to MC Refl while the laser power was low, but now we don't want to fry the PD.

* Noticed that the MCWFS path is totally wrong.  Someone (Yuta?) wanted to use the MCWFS as a reference, but the steering mirror in front of WFS1 was switched out, and now no beam goes to WFS2 (it's blocked by part of the mount of the new mirror). I have not yet fixed this, since I wasn't using the WFS tonight, and had other things to get done.  We will need to fix this.

* Realigned the MC Refl path to optimize MC Refl again, with the new mirror.

* Replaced the last steering mirror on the PSL table before the beam goes into the chamber from a BS1-1064-33-1025-45S to a Y1-45S.  I would have liked a Y1-0deg mirror, since the angle is closer to 0 than 45, but I couldn't find one.  According to Mott's elog 2392 the CVI Y1-45S is pretty much equally good all the way down to 0deg, so I went with it.  This undoes the change of keeping the laser power in the chambers to a nice safe ~50mW max while we were at atmosphere.

* Put the HWP in front of the laser back to 267deg, from its temporary place of 240deg.  The rotation was to keep the laser power down while we were at atmosphere.  I put the HWP back to the place that Kevin had determined was best in his elog 3818.

* Tried to quickly align the Xarm by touching the BS, ITMX and ETMX.  I might be seeing IR flashes (I blocked the green beam on the ETMX table so I wouldn't be confused.  I unblocked it before finishing for the night) on the CCD for the Xarm, but that might also be wishful thinking.  There's definitely something lighting up / flashing in the ~center of ETMX on the camera, but I can't decide if it's scatter off of a part of the suspension tower, or if it's really the resonance. 

What happened in the end:

The MC Trans signal on the MC Lock screen went up by almost an order of magnitude (from ~3500 to ~32,000).  When the count was near ~20,000 I could barely see the spot on a card, so I'm not worried about the QPD.  I do wonder, however, if we are saturating the ADC. Suresh changed the transimpedance of the MC Trans QPD a while ago (Suresh's elog 3882), and maybe that was a bad idea? 

Xarm not yet locked. 

Can't really see flashes on the Test Mass cameras. 

 

  4105   Tue Jan 4 13:57:48 2011 kiwamuUpdateIOOincident mirror changed from 45deg to 0 deg

I replaced the final steering mirror (Y1-1037-45-S) in the zig-zag path on the PSL table by a 0 deg mirror Y1-1037-0.

With a sensor card I confirmed the transmission reduced a lot after the replacement.

As we expected, the replacement of the mirror caused a mis-alignment of the incident beam axis to the MC, so I compensated it by touching the angle of the mirror a little bit.

After the alignment of the mirror, the MC is still resonating at TEM00.

We will check the spot positions more accurately by A2L technique.

Quote:

- Y1-45S has 4% of transmission. Definitively we like to use Y1-0 or anything else. There must be the replaced mirror. 

I think Suresh replaced it. So he must remember wher it is.

  4106   Tue Jan 4 15:12:33 2011 SureshUpdateIOOMC Trans Mon QPD gain decreased by 10

 Decreased the gain of MC-Trans-Mon QPD ckt

The resistors R1, R2, R3, R4 are now 49.9 kOhm. The previous elog on this subject 3882 has the ckt details. 

  4107   Tue Jan 4 18:37:18 2011 JenneUpdateIOOMCWFS aligned

I undid Yuta's temporary setup, and put beam back on both WFS.  Since Koji had just aligned the Mode Cleaner, I centered the beam on the WFS using the WFS QPD screen, while watching the WFS Head screen, to make sure that the beam was actually hitting the QPD, and not off in lala land. 

Quote from Koji:

- We must check the MCWFS path alignment and configuration.

Quote from Jenne:

* Noticed that the MCWFS path is totally wrong.  Someone (Yuta?) wanted to use the MCWFS as a reference, but the steering mirror in front of WFS1 was switched out, and now no beam goes to WFS2 (it's blocked by part of the mount of the new mirror). I have not yet fixed this, since I wasn't using the WFS tonight, and had other things to get done.  We will need to fix this.

 

  4108   Tue Jan 4 21:21:57 2011 kiwamuUpdateIOOPZTs are connected to c1iscaux

I connected PZT1 and PZT2 to a slow front end machine c1iscaux.

Now we are able to align these PZTs from the control room via epics.

 

   Since we removed C1ASC that was controlling the voltage applied on the PZTs, we didn't have the controls for them for a long time.

So Rana and I decided to hook them up to an existing slow front end machine temporarily.

(probably the best solution is to connect them to C1LSC, which is fast enough to dither them.)

We actually found that c1iscaux is the proper machine, because it looked like it used to control the PZTs a long long time ago.

Moreover, c1iscaux still has DAC channels named like C1:LSC-PZT1_X, and so on.

 

  Below shows a screen shot of the medm screen for controlling the PZTs, invoked from a button on sitemap.adl ( pointed by a black arrow in the picture below)

The current default values are all zero at the right top sliders.

Screenshot20110104.png

  4110   Wed Jan 5 03:06:02 2011 kiwamuUpdateIOObeam spots on MC mirrors

I checked the spot positions on MC1 and MC3 by running Yuta's A2L script.

The amounts of the off-centering were good except for YAW of MC1.

 So we have to adjust the YAW alignment of the beam axis by steering the mirrors at the PSL table.

- - - (measured off-centering) - - - 

MC1_PIT  =  -0.711 mm

MC1_YAW =  1.62 mm

MC3_PIT  =   -0.0797 mm

MC3_YAW  =  - 0.223 mm

 

Quote:

We will check the spot positions more accurately by A2L technique.

 

ELOG V3.1.3-