40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log, Page 272 of 344  Not logged in ELOG logo
ID Date Author Type Category Subjectup
  8219   Mon Mar 4 11:30:47 2013 SteveUpdatePEMair cond problem


 The air cond is out of order at the area covered by racks 1 X 1  through 1 X 7

The arm X and Y AC units are working.

Attachment 1: 40dAC.png
  2972   Mon May 24 07:53:57 2010 steveConfigurationPEMair cond. just turned ON

IFO room temp 27.5C , Please remember to turn AC back on !

Attachment 1: acoff.jpg
  1347   Tue Mar 3 08:44:31 2009 steveUpdatePEMair cond. maintenance today
IFO room 104 air conditions will be shut down for maintenance today.
This should be finished by noon.
The temperature and particle count variation can be more than usual.
  12712   Fri Jan 13 14:18:28 2017 SteveUpdatePEMair condition fixed

The old control room AC  has been stick in heating mode for about 2 months. It's thermostate and fan belt  was finally replaced. It was calibrated and set to 71 F ( just behind 1X6 on west wall ) around 1pm.

Out belt; sad inside 

at 4 pm Rana cried

It must be too tight.

Attachment 1: PEM_120d.png
  3192   Mon Jul 12 10:23:51 2010 steveUpdatePEMair condition maintenance is today

The AC filters will be checked and/or replaced today. This means the AC will be off for sort periods of time. Temperature and particle count will be effected some what.

See 800 days plot

Attachment 1: pem2y.jpg
  13046   Wed Jun 7 10:07:00 2017 SteveUpdatePEMair condition thermostate

The Y arm ac thermostate was calibrated after cooling water relay replacement by Mike.... yesterday. The set temp is remaind to be 70F

The east end south wall temp is reading 22C

  3297   Tue Jul 27 11:43:24 2010 steveUpdatePEMair quality is bad today

The lab is at 30,000 and Pasadena air is at 1.1 e+6 particles /cf min of 0.5 micron.

Attachment 1: pemtoday.jpg
  200   Wed Dec 19 11:31:01 2007 steveOmnistructurePEMaircond filter maintenance
Jeff is working on all air condiontion units of the 40m lab
This we do every six months.
Attachment 1: acfilters6m.jpg
  2831   Thu Apr 22 09:03:54 2010 steveOmnistructurePEMaircondition can not be turned off

Koji and I wanted to turn off the IFO-room AC so the wind would not blow on MC1-3. We could not. The switches were probably bypassed when the power transformer was replaced at the last scheduled power outage.

  3623   Wed Sep 29 18:28:32 2010 yutaUpdateComputersaldabella connects to the wireless network

 We need laptops that connect to the wireless network to use them in the lab.

 Dell Inspiron E1505 laptop
 Broadcom Corporation BCM4311 802.11b/g WLAN (rev 01) (PCIID: 14e4:4311 (rev 01))

What I did:
1. I followed this method(Japanese!): http://www.linuxmania.jp/wireless_lan.html
 Except I installed ndiswrapper-1.56 and cabextracted sp32156.exe.
 Also, I didn't run
  # ndiswrapper -m

2. Then I did step #6 in here: http://nodus.ligo.caltech.edu:8080/40m/1275
 Note that the hardware is eth1 instead of wlan0.

3. Added the following line to /etc/rc.d/rc.local to make ndiswrapper load on every boot:
 /sbin/modprobe ndiswrapper

 aldabella now connects to the wireless martian network on every boot!!

 Somehow, the method that uses Broadcom official driver doesn't work.
 It returns the following error when activating eth1:
  Error for wireless request "Set Encode" (8B2A) :
    SET failed on device eth1 ; Invalid argument.
  Error for wireless request "Set Encode" (8B2A) :
    SET failed on device eth1; Invalid argument.

  3541   Tue Sep 7 23:49:08 2010 sanjitConfigurationComputersaldabella network configuration


added name server as the first entry in /etc/resolv.conf

changed the host IPs in /etc/hosts to 192.168.xxx.yyy

made: localhost.localdomain localhost

::1 localhost6.localdomain6 localhos6

as the first two lines of /etc/hosts


/cvs/cds mounts

on ethernet, DNS look-up works without the explicit host definitions in /etc/hosts,

but those entries are needed for wifi only connection.


  106   Thu Nov 15 18:06:06 2007 tobinUpdateComputersalex: linux1 root file system hard disk's dying
I just noticed that Alex made an entry in the old ilog yesterday, saying: "Looks like linux1 root filesystem hard drive is about to die. The system log is full of drive seek errors. We should get a replacement IDE drive as soon as possible or else the unthinkable could happen. 40 Gb IDE hard drive will be sufficient."
  9080   Wed Aug 28 06:17:15 2013 manasaUpdateComputer Scripts / Programsalias for MATLAB2010

Although Matlab 2013 has not been causing any visible trouble so far, it takes a while to startup.

I have added alias 'ml10' to bash to start Matlab 2010 from the terminal for convenience.

  3929   Tue Nov 16 03:33:22 2010 yutaUpdateIOOaligned Faraday, beam reached SM just before PRM

(Koji, Yuta)

We aligned the Faraday after MC and we are now ready to install PRM.

  MC was roughly aligned (beam spot ~0.7mm from the actuation center).
  So, we started aligning in-vac optics.
  First thing to align was the Faraday after MC3.

What we did:
  1. Ran A2L.py for confirmation.(Second from the last measurement point on the A2L result plot)

  2. Aligned the Faraday so that MC3 trans can go through it. We moved the Faraday itself, while we didn't touch IM2.
     We turned the pitch nob of the last steering mirror at PSL table in CCW slightly in order to lower the beam at the Faraday by ~1mm.

  3. During the alignment, we found that the polarization of the incident beam was wrong. It should have been S but it was P.
     As there is the HWP right before the EOM, Rana rotated it so as to have the correct polarization of S on the EOM and the MC.
     Note that the PMC and the main interferometer are configured to have P-pol while the MC is to have S-pol.

  4. Setup the video camera to monitor the entrance aperture of the Faraday. It required 4 steering mirrors to convey the image to the CCD.

  5. Moved all of the OSEMs for MC1 and MC3 so that the sensor output can have roughly half of their maxima.

  6. Ran A2L.py. (The last measurement point on the A2L result plot)

  7. Aligned the IO optics so that the beam goes Faraday -> MMT1 -> MMT2 -> SM3.


  1. OSEM sensor outputs for MC1 and MC3 are;

(V) MC1 MC3
max current value max current value
ULSEN 1.3 0.708 1.37 0.699
URSEN 1.4 0.845 1.71 0.796
LRSEN 1.45 0.743 1.77 0.640
LLSEN 1.56 0.762 1.56 0.650
SDSEN 1.67 0.801 1.59 0.821

  2. A2L result is;

     The beam position slightly got lower(~0.2mm), because we touched SM at PSL table.
     Alignment slider values changed because we moved MC1 and MC3 OSEMs.

  3. Now, MC_RFPD_DCMON is ~0.39 when MC unlocked and ~0.083 when locked.
     So, the visibility of MC is ~79% (for S-pol).

  4. Now the incident beam to the MC has S polarization, the cavity has higher finesse. This results the increased MC trans power.
     It was ~8e2 when the polarization was P, now it is ~4.2e3 when the MC is locked.

  5. The beam reached SM3 at BS table. The alignment of the SM2, MMT1, MMT2 were confirmed and adjusted.

  6. All pieces of the leftover pizza reached my stomach.

  - Install PRM to the BS chamber.
  - Align PRM and get IFO reflection beam out to the AP table

  6713   Wed May 30 01:35:15 2012 yutaUpdateGreen Lockingaligned Y arm green beam

[Jenne, Yuta]

We aligned the Y arm for IR (C1:LSC-TRY_OUT is now ~ 0.9), and aligned the green beam from the ETMY table. The Y arm green is now resonating in TEM00 mode, but we need some monitors (green trans or green refl) to maximize the coupling.

We noticed that the MC beam spot are oscillating at ~ 1 Hz, mostly in YAW.  This wasn't observable before the PMC realignment (elog #6708). We should find out why and fix it.

  6798   Tue Jun 12 01:58:33 2012 yutaUpdateGreen Lockingaligned Y arm to Y end green

[Jenne, Yuta]

We aligned Y arm to the Y end green incident beam.
We noticed two TEM00, bright and dim, so we decreased Y end laser temperature to 34.13 deg C.
It doubled the transmission of the green, and now the transmission to the PSL table is 178 uW, which is close to the maximum(197 uW) we got so far.

Current settings for Y end laser is;

  Y end laser "T+": 34.049 deg C
  Y end laser "ADJ": 0
  Y end laser measured temperature: 34.13 deg C
  Y end slow servo: on (was off)

We aligned IR beam to the Y arm by mostly adjusting PZTs and got the transmission, C1:LSC-TRY_OUT ~ 0.9.

We tried to calculate the mode-matching ratio for IR by taking TRY data while ITMY and ETMY are swinging (without ALS), but it was difficult because we see too many higher order modes.

Tomorrow, we will (1) connect the beatbox to ADC, (2) edit c1gcv model, (3) scan the arm using I-Q signals.

  1327   Thu Feb 19 23:50:31 2009 peteUpdateLockingaligned pd's on AP table

Yoichi, Peter

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



  4016   Mon Dec 6 22:18:39 2010 kiwamuUpdateGreen Lockingaligned the beam axis

 [Suresh and Kiwamu]

We aligned the green beam to the X arm cavity more carefully.

Now the green beam is hitting the centers of ETMX, ITMX and BS.

Also we confirmed that the green beam successfully comes out from the chamber to the PSL table.


(what we did)

- opened the BS, ITMX and ETMX chambers. 

- checked the positions of the beam spots on ITMX, BS and ETMX

   The spot position on ETMX was fine,

   But at BS and ITMX, the spots were off downward.

   We decided to move the beam angle by touching a steering mirror at the end green setup.

- changed the beam axis by touching the steering mirror at the end station.

- checked the spot positions again, they all became good. It looks the errors were within ~ 1mm.

- moved the position of a TT, which is sitting behind the BS, by ~10mm, because it was almost clliping the beam.

- aligned the green optics

- got the beam coming out from the chamber. 



  7658   Thu Nov 1 19:28:48 2012 JenneUpdateAlignmentaligned, AS beam on camera

After everyone else did the hard work, I moved the AS first-on-the-table steering mirror sideways a bit so the AS beam is on the center of the mirror, then steered the beam through the center of the lens, onto the 2" 99% BS.  I also moved the camera from it's normal place (the 1% transmitted through that BS) to the AS110 PD path, as we did last vent.  We'll need to put it back before we go back to high power.

  7657   Thu Nov 1 19:26:09 2012 jamieUpdateAlignmentaligned, this time without the crying

Jamie, Jenne, Nic, Manasa, Raji, Ayaka, Den

We basically walked through the entire alignment again, starting from the Faraday.  We weren't that far off, so we didn't have to do anything too major.  Here's basically the procedure we used:

  • Using PZT 1 and 2 we directed the beam through the PRM aperture and through an aperture in front of PR2.  We also got good retro-reflection from PRM (with PRM free-hanging).  This completely determined our input pointing, and once it was done we DID NOT TOUCH the PZT mirrors any more.
  • The beam was fortunately still centered on PR2, so we didn't touch PR2.
  • Using PR3 we direct the beam through the BS aperture, through the ITMY aperture, and to the ETMY aperture.  This was accomplished by loosening PR3 and twisting it to adjust yaw, moving it forward/backwards to adjust the beam translation, and tapping the mirror mount to affect the hysteresis to adjust pitch.  Surprisingly this worked, and we were able to get the beam cleanly through the BS and Y arm apertures.  Reclamped PR3.
  • Adjusted ITMY biases (MEDM) to get Michelson Y arm retro-reflecting to BS.
  • Adjusting BS biases (MEDM) we directed the beam through the ITMX and ETMX apertures.
  • Adjusted ITMX biases (MEDM) to get Michelson X arm retro-reflecting to BS.

At this point things were looking good and we had Michelson fringes at AS.  Time to align SRC.  This is where things went awry yesterday.  Proceeded more carefully this time:

  • Loosened SR3 to adjust yaw pointing towards SRM.  We were pretty far off at SRM, but we could get mostly there with just a little bit of adjustment of SR3.  Got beam centered in yaw on SR2.
  • Loosened and adjusted SR2 to get beam centered in yaw on SRM.
  • Once we were centered on SR3, SR2, and SRM reclamped SR2/SR3.
  • Pitch adjustment was the same stupid stupid jabbing at SR2/3 to get the hysteresis to stick at an acceptable place.**
  • Looked at retro-reflection from SRM.  We were off in yaw.  We decided to adjust SRM pointing, rather than go through some painful SR2/3 iterative adjustment.  So unclamped SRM and adjusted him slightly in yaw to get the retro-reflection at BS.

At this point we felt good that we had the full IFO aligned.  We were then able to fairly quickly get the AS beam back out on the AS table.

We took at stab at getting the REFL beam situation figured out.  We confirmed that what we thought was REFL is indeed NOT REFL, although we're still not quite sure what we're seeing.  Since it was getting late we decided to close up and take a stab at it tomorrow, possibly after removing the access connector.

The main tasks for tomorrow:

  • Find ALL pick-off beams (POX, POY, POP) and get them out of the vacuum.  We'll use Jenne's new Suresh's old green laser pointer method to deal with POP.
  • Find all OPLEV beams and make sure they're all still centered on their optics and are coming out cleanly.
  • Center IPPOS and IPANG
  • Find REFL and get it cleanly out.
  • Do a full check of everything else to make sure there is no clipping and that everything is where we expect it to be.

Then we'll be ready to close.  I don't see us putting on heavy doors tomorrow, but we should be able to get everything mostly done so that we're ready on Monday.

** Comment: I continue to have no confidence that we're going to maintain good pointing with these crappy tip-tilt folding mirrors.


  6789   Fri Jun 8 15:08:27 2012 yutaUpdateGreen Lockingaligned/mode-matched Y green beat setup

Laser temperature settings for Y arm green work today are;

  PSL laser temperature on display: 31.38 deg C (PSL HEPA 100%)
  C1:PSL-FSS_SLOWDC = 1.68
  Y end laser "T+": 34.049 deg C
  Y end laser "ADJ": 0
  Y end laser measured temperature: 34.13 deg C (*)

Green transmission from Y end and PSL green power on the beat PD are;

  P_Y = 28 uW
  P_PSL = 96 uW

P_Y decrease from its maximum we got (75 uW, see elog #6777) is because the alignment for Y arm green is decreased. I can see the decrease from the green reflection on ETMT camera, but I will leave it because we already have enough beat.

I aligned PSL optics, including the mode-matching lens to maximize the beat note. The beat note I got is about 26dBm.
The calculated value is -14 dBm, so we have about 75 % loss.
I measured the reflection from the PD window and its reflectivity was about 30%. We still have unknown 45% loss.

  1764   Mon Jul 20 12:35:21 2009 robConfigurationLockingalignment biases funny

I found the alignment biases for the PRM and the SRM in a funny state.  It seemed like they had been "saved" in badly misaligned position, so the restore scripts on the IFO configure screen were not working.  I've manually put them into a better alignment.

  7408   Wed Sep 19 09:32:24 2012 SteveUpdateSUSalignment centering jig

SOS alignment tool with ID 9.5 and 6.3 mm

Attachment 1: IMG_1639.JPG
Attachment 2: IMG_1651.JPG
  4044   Sat Dec 11 00:41:55 2010 kiwamuUpdateIOOalignment of IP_ANG is done

  [Jenne, Koji and Kiwamu]

 We finished a coarse alignment of IP_ANG.

 The beam for IP_ANG successfully reached to the ETMY chamber and is ready for the final alignment.

 (Additionally we again tried looking for a resonance for TEM00 in the X arm, but we obtained only flashes of some higher order modes.)

--- what we did

 * installed the steering mirrors for IP_ANG and IP_POS.

 * checked PZT1 if it worked correctly or not. It was healthy.

 * neutralized and realigned PZT1.

 * flipped a window, which is standing before PRM, because the wedged side of the window was at wrong side.

 * realigned PZT2 and checked the spot positions on the TTs.

 * repositioned more carefully the TTs and aligned them to the correct angles.

 * aligned the beam to the center of both the BS and ITMY by rotating the last TT.

 * aligned the beam more precisely by tweaking PZT2 while looking at the spot at the Y end.

         The beam is still hitting the center of ETMY.

 * aligned the steering mirror for IP_ANG while looking at the spot at the Y end.

        In fact IP_ANG is visible with a card. 

 * aligned the BS by looking at the spot on ITMX.

 * covered ETMX with aluminum foil, and made a ~1cm hole on the foil as a target.

         The hole was placed on the center of ETMX.

 * more precisely aligned the BS by looking at the spot on the aluminum foil.

         The spot was clearly visible on CCD monitor.

 * aligned the ITMX by looking at a spot on the foil. The spot represented the beam reflected by ITMX back to ETMX.

 * saw flashes on the foil but couldn't make it TEM00 because it was difficult to see any flashes on the surface of either ETMX or ITMX.

        It means the flashes are visible only when the beam is hitting some scattering surface.

        The mirror surface of the test masses are less lossy than that of the old test masses ??



  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.

  5244   Tue Aug 16 04:25:34 2011 Suresh, KiwamuUpdateSUSalignment of MC output to Y-arm using PZTs

We did several things today+night.  The final goal was to lock the PRC so that we could obtain the POX, POY and POP beams.  However there were large number of steps to get there.

1) We moved the ITMY into its place and balanced the table

2) We then aligned the Y-arm cavity to the green beam which was set up as a reference before we moved the ETMY and ITMY to adjust the OSEMS.  We had the green flashing in Y-arm

3) We checked the beam position on PR2. It was okay. This confirmed that we were ready to send the beam onto the Y arm.

4) We then roughly aligned the IR beam on ETMY where Jamie had placed an Al foil with a hole.  We got the arm flashing in both IR and green. 

5) We used the PZTs to make the green and IR beams co-incident and flashing in the Y arm.  This completed the alignment of the IR beam into the Y-arm.

6) The IPPO (pick-off) window had to be repositioned to avoid clipping.  The IPANG beam was aligned such that it exits the ETMY chamber onto the ETMY table.  It can now be easily sent to the IPANG QPD.

7) Then BS was aligned to direct the IR beam into the X-arm and had the X-arm flashing.  It had already been aligned to its green.

8) It was now the turn of the SRC.  The beam spots on all the SRC related optics were off centered.  We aligned all the optics in the AS path to get the AS beam on to the AP table.

9) The AS beam was very faint so we repositioned the AS camera to the place intended for AS11 PD, since there was a brighter beam available there. 

10) We could then obtain reflections from ITMY, ITMX and PRM at the AS camera. 

11) Problems:

      a) ITMY osems need to be readjusted to make sure that they are in mid-range.  Several are out of range and so the damping is not effective.

      b) When we tried to align SRC the yaw OSEM had to be pushed to its full range.  We therefore have to turn the SRM tower to get it back into range.

 12)  We stopped here since moving the SRM is not something to be attempted at the end of a rather long day. Kiwamu is posting a plan for the rest of the day.

  7919   Fri Jan 18 15:08:13 2013 jamieUpdateAlignmentalignment of temporary half PRC

[jenne, jamie]

Jenne and I got the half PRC flashing.  We could see flashes in the PRM and PR2 face cameras.

We took out the mirror in the REFL path on the AP that diverts the beam to the REFL RF pds so that we could get more light on the REFL camera.  Added an ND filter to the REFL camera so as not to saturate.

  7736   Wed Nov 21 01:31:37 2012 Koji, AyakaUpdateLockingalignment on ETMX table

Since the transmission beam on ETMXT camera seemed to be clipped, we checked the optics on ETMX table.

We aligned the lens so that it is orthogonal to the beam, then the beam shape looks fine.


Also we removed some an-used optics which were used for fiber input.

  7635   Sat Oct 27 23:13:12 2012 ranaUpdateAlignmentalignment strategy

 Maybe we have already discarded this idea, but why not do the alignment without the MC?

Just lock the green beam on the Yarm and then use the transmitted beam through the ITMY to line up the PRC and the PZTs? I think our estimate is that since the differential index of refraction from 532 to 1064 nm is less than 0.01, using the green should be OK. We can do the same with the Xarm and then do a final check using the MC beam.

In this way, all of the initial alignment can be done with green and require no laser Goggles (close the shutter on the PSL NPRO face).

  14603   Fri May 10 18:24:29 2019 gautamUpdateNoiseBudgetaligoNB

I pulled the aligoNB git repo to /ligo/GIT/aligoNB/aligoNB. There isn't a reqs.txt file in the repo so installing the dependencies on individual workstations to get this running is a bit of a pain. I found the easiest thing to do was to setup a virtual environment for the python3 stuff, this way we can run python2 for the cdsutils package (hopefully that gets updated soon). I'm setting up a C1 directory in there, plan is to budget some subsystems like Oplev, ALS for now, and develop the code for the eventual IFO locking. As a test, I ran the H1 noise budget (./aligonb H1), works, so looks like I got all the dependencies...

  7529   Thu Oct 11 11:57:40 2012 jamieUpdateCDSall IOP models rebuild, install, restarted to reflect fixed ADC/DAC layouts


As Rolf pointed out when he was here yesterday, all of our IOPs are filled with parts for ADCs and DACs that don't actually exist in the system.  This was causing needless module error messages and IOP GDS screens that were full of red indicators.  All the IOP models were identically stuffed with 9 ADC parts, 8 DAC parts, and 4 BO parts, even though none of the actual front end IO chassis had physical configurations even remotely like that.  This was probably not causing any particular malfunctions, but it's not right nonetheless.

I went through each IOP, c1x0{1-5}, and changed them to reflect the actual physical hardware in those systems.  I have committed these changes to the svn, but I haven't rebuilt the models yet.  I'll need to be able to restart all models to test the changes, so I'm going to wait until we have a quiet time, probably next week.

I finally got around to rebuilding, installing, and restarting all the IOP models.  Everything went smoothly.  I had to restart all the models on all the screens, but everything seemed to come back up fine.  We now have many fewer dmesg error messages, and the GDS_TP screens are cleaner and don't have a bunch of needless red.

A frame builder restart was also required, due to name changes in unused (but unfortunately still needed) channels in the IOP.

  11426   Sat Jul 18 14:55:33 2015 jamieUpdateGeneralall front ends back up and running

After some surgery yesterday the front ends are all back up and running:

  • Eric found that one of the DAC cards in the c1sus front end was not being properly initialized (with the new RCG code).  Turned out that it was an older version DAC, with a daughter board on top of a PCIe board.  We suspected that there was some compatibility issue with that version of the card, so Eric pulled an unused card from c1ioo to replace the one in c1sus.  That worked and now c1sus is running happily.
  • Eric put the old DAC card into c1ioo, but it didn't like it and was having trouble booting.  I removed the card and c1ioo came up fine on it's own.
  • After all front end were back up and running, all RFM connections were dead.  I tracked this down to the RFM switch being off, because the power cable was not fully seated.  This probably happened when Steve was cleaning up the 1X4/5 racks.  I re-powered the RFM switch and all the RFM connections came back on-line
  • All receivers of Dolphin (DIS) "PCIE" IPC signals from c1ioo where throwing errors.  I tracked this down to the Dolphin cable going to c1ioo being plugged in to the wrong port on the c1ioo dolphin card.  I unplugged it and plugged it into the correct port, which of course caused all front end modules using dolphin to crash.  Once I restarted all those models, everything is back:

  5325   Tue Aug 30 14:33:52 2011 jamieUpdateCDSall front-ends back up and running

All the front-ends are now running.  Many of them came back on their own after the testpoint.par was fixed and the framebuilder was restarted.  Those that didn't just needed to be restarted manually.

The c1ioo model is currently in a broken state: it won't compile.  I assume that this was what Suresh was working on when the framebuilder crash happened.  This model needs to be fixed.

  8129   Thu Feb 21 15:21:07 2013 yutaUpdateVACall heavy doors on, started pumping down annulus

[Steve, Manasa, Jenne, Sendhil, Evan, Yuta]

We put heavy doors on ITMX/ITMY/BS chamber and started pumping down from annulus.

What we did:
  1. Replaced POP55 with AS55 back, because it was not broken.
  2. Centered on AS55, REFL55, REFL11, POPDC PD.
  3. Tried to lock PRMI, but I couldn't lock even MI stably for more than 1 min. I believe this is because it was noisy this morning. But I checked again that REFL/POP/AS beams are coming out without clipping and we have some error signals.
  4. Noticed AS beam has less range in left (on AS camera), so we tweaked OM4 a little to make more room.
  6. Took pictures inside ITMX and BS chambers
  7. Put heavy doors on ITMX/ITMY/BS chambers.
  8. Started pumping down annulus.
  9. Recentered IPANG/IPPOS and oplevs on their QPDs.


  1197   Fri Dec 19 16:38:09 2008 steveUpdateLSCall optlevs centered
All optlevs were centered after full alignment.

Qpd sums are:
ETMX 12,229 counts
ITMX 9,932
ETMY 12,043
ITMY 4,362
BS 1,880
PRM 1,423
SRM 11,641
  10132   Mon Jul 7 09:46:00 2014 SteveConfigurationSUSall sus damping restored

All suspension damping restored. There had to be an earth quake.

Attachment 1: 6.9MagMexico.png
  2036   Thu Oct 1 14:22:28 2009 robUpdateSUSall suspensions undamped



 The EQ did not change the input beam pointing. All back to normal, except MC2 wachdogs tripped again.

 Round 3 for the day of MC2 watchdogs tripping.

 I've watchdogged all the suspensions while I mess around with computers.  If no one else is using the IFO, we can leave them undamped for a couple of hours to check the resonant frequencies, as long as I don't interrupt data streams with my computer hatcheting.

  2039   Thu Oct 1 19:18:24 2009 KojiUpdateSUSall suspensions undamped

Ops. I restored the damping of the suspensions at around 16:30.




 The EQ did not change the input beam pointing. All back to normal, except MC2 wachdogs tripped again.

 Round 3 for the day of MC2 watchdogs tripping.

 I've watchdogged all the suspensions while I mess around with computers.  If no one else is using the IFO, we can leave them undamped for a couple of hours to check the resonant frequencies, as long as I don't interrupt data streams with my computer hatcheting.


  13279   Thu Aug 31 00:46:57 2017 ranaSummaryCDSallegra -> Scientific Linux 7.3

I made a 'LiveCD' on a 16 GB USB stick using this command after the GUIs didn't work and looking at some blog posts:

sudo dd if=SL-7.3-x86_64-2017-01-20-LiveCD.iso of=/dev/sdf


Debian doesn't like EPICS. Or our XY plots of beam spots...Sad!


No, not confused on that point. We just will not be testing OS versions at the 40m or running multiple OS's on our workstations. As I've said before, we will only move to so-called 'reference' systems once they've been in use for a long time.

Ubuntu16 is not to my knowledge used for any CDS system anywhere.  I'm not sure how you expect to have better support for that.  There are no pre-compiled packages of any kind available for Ubuntu16.  Good luck, you big smelly doofuses. Nyah, nyah, nyah.

K Thorne recommends that we use SL7.3 with the 'xfce' window manager instead of the Debian family of products, so we'll try it out on allegra and rossa to see how it works for us. Hopefully the LLO CDS team will be the tip of the spear on solving the usual software problems we have when we "~up" grade.

  6685   Fri May 25 17:52:08 2012 JamieUpdateComputersallegra now running Ubuntu 10.04

The last of the control room machines is now upgraded.

  1467   Fri Apr 10 01:24:08 2009 ranaUpdateComputersallegra update (sort of)

I tried to play an .avi file on allegra. In a normal universe this would be easy, but because its linux I was foiled.

The default video player (Totem) doesn't play .avi or .wmv format. The patches for this work in Suse but not Fedora. Kubuntu but not CentOS, etc.I also tried installing Kplayer, Kaffeine, mplayer, xine, Aktion, Realplay, Helix, etc. They all had compatibility issues with various things but usuallylibdvdread or some gstreamer plugin.So I pressed the BIG update button. This has now started and allegra may never recover. The auto update wouldn't work in default mode becauseof the libdvdread and gstreamer-ugly plugins, so I unchecked those boxes. I think we're going to have this problem as long as we used any kind ofadvanced gstreamer stuff for the GigE cameras (which is unavoidable).


  1007   Mon Sep 29 15:09:36 2008 steveUpdatePSLalmost 4 yrs plot of power & temps
The water chiller is normally running 1.5 C warmer than the laser head temp.
When control room temp is stable and PEM-count_temp is stable we can expect the head temp to be stable 20.0 C

PSL-126MOPA_HTEMP is running warmer in the last ~40 days

The ifo arm thermostate temp settings were raised by 2 F on 8-11-08
Attachment 1: 3.5y.jpg
  2048   Mon Oct 5 02:51:08 2009 robUpdateLockingalmost there

Working well tonight: the handoff of CARM to RF (REFL2I), successful reduction of CARM offset to zero, and transition control of MCL path to the OUT1 from the common mode board.  All that's left in lock acquisition is to try and get the common mode bandwidth up and the boost on.

  11177   Fri Mar 27 04:36:46 2015 denUpdateLSCals->pdh transition, prcl on 1f, alignment

Tonight I have modified transition steps from als to pdh signals. I have added 1:20 filters to CARM_A and DARM_A filter banks to make them unconditionally stable. These filters made locking more robust -- duty cycle is was ~70% tonight. I have also modified slow/ao crossover to avoid ringing up of lines above 1kHz.

Once AO is engaged with high bandwidth, REFL55 signal looks good and I transition PRCL from 165I to 55I. Optical gain compared to PRMI reduced from 55I/165I = -330 down to 55I/165I = 30 in full lock.

I worked on alignment of ETMs. Looking on the cameras I could improve arm power up to 160 and ifo visibility was 80%. POP22 fluctuated by ~50% and every few minutes we loose lock because POP22 almost touches zero.

  11179   Fri Mar 27 14:47:57 2015 KojiUpdateLSCals->pdh transition, prcl on 1f, alignment

Jenne and I interviewd Den this afternoon to make the things clear

- His "duty cycle" is not about the lengths of the lock stretch. He saids, the transition success probability is improved.

- For this improvement, the CARM transition procedure was modified to include turning on 1:20 (Z1P20) filter in CARM_A (i.e. ALS) once CARM_B (i.e. RF) dominates the loop in all frequency.

- I think this transition can be summarized like the attachment. At STEP4, the integration of the ALS is reduced. This actually does not change the stability of the servo as the servo stability is determined by the stability of the CARM_B loop. But this does further allow CARM_B to supress the noise. Or in other word, we can remove the noise coming from the CARM_A loop.

- The POP22 issue: Jenne has the trigger signal that is immune to this issue by adding some amount of POPDC for the trigger.
We can avoid the trigger issue by this technique. But if the issue is due to the true optical gain fluctuation, this may mean that the 11MHz optical gain is changing too much. This might be helped by PRC angular feedforward or RF 22MHz QPD at POP.

Attachment 1: CARM_transition.pdf
  193   Mon Dec 17 11:47:13 2007 albertoUpdateElectronicsan alternative design for the RFAM monitor's filter at 33Mhz
Since the Butterworth turned out o be rather wide-band, I tried an other configuration for the 33 MHz filter. Attached are the simulated transfer function and the measured. As one can see, the measured peak is much broader than expected.
Attachment 1: RFSim99-33MHz.png
Attachment 2: RF99-SimmButterworthPrototype.png
Attachment 3: RFSim99-33MHz-TFplot.png
  6828   Mon Jun 18 02:31:43 2012 yutaSummaryGreen Lockinganalysis of mode scan data

I analyzed mode scan data from last week.
Mode matching ratio for Y arm is 86.7 +/- 0.3 %. Assuming we can get rid of TEM01/10 by alignment, this can be improved up to ~ 90%.

Peak search, peak fitting and finnesse calculation:
  I made a python script for doing this. It currently lives in /users/yuta/scripts/modescanresults/analyzemodescan.py.
  What it does is as follows

  1. Read mode scan data(coarse5FSRscan.csv, fine1FSRscan.csv). Each column in the data file should be

[time] [some thing like C1:ALS-BEAT(Y|X)_(COARSE|FINE)_(I|Q)_IN1] [C1:LSC-POY11_I_ERR] [C1:LSC-TRY_OUT]

Each separated by comma. Currently, this script uses only TRY, but it reads all anyway

  2. Find peak in TRY data. For the peak search, it splits data in 1 sec and find local maximum. If the local maximum is higher than given threshold, it recognize it as a peak. If two peaks are very close, it uses higher one. This sometimes fails, because mode scan data we have is not so nice.

  3. Fit each peak with Lorentzian function,

TRY = a*b/(4*(t-c)^2+b^2) + d  (a>0, b>0)

  where a/b is a peak height, b is a linewidth (FWHM), c is a peak position in time, and d is a offset.
  I don't like this, but currently, a/b+c is fixed to the maximum value of TRY data used for fitting. This is because sometimes TRY data is so bad and I couldn't get the peak height correctly. Each points of TRY data doesn't have same error because cavity length is fluctuating and relation between cavity length and TRY is not linear. I think I should use some weighting for the fit, but currently, I just use least squares.

  4. Find TEM00 and calculate FSR in "seconds". I just used "seconds" assuming we did a linear sweep. This script recognize TEM00 from the given threshold.

  5. Calculate finesse using FSR and linewidth of the closest TEM00.

  Below are the result plots from this analysis. Calculated finesse looks quite high (~1000). I think this is from non-linearity in the sweep and error in "measured" line width.

Higher order modes and RF sidebands:

  Assuming the curvature of ITMY/ETMY are flat/57.5 m, Y arm length is 38.6 m(FSR 3.9 MHz), positions of HOMs and RF sidebands(11/55 MHz) in frequency domain should look like the plot below.
  The script for calculating this currently lives in /users/yuta/scripts/modescanresults/HOMRFSB.py, inspired by Yoichi's script for KAGRA

Mode-matching ratio:
  By comparing mode scan data and HOM/RF SB positions in a sophisticated way, you can tell which peak is which.

  From COARSE 5FSR measurement, peak heights are

TEM00 0.884, 0.896, 0.917, 0.905, 0.911
TEM01 0.040, 0.037, 0.051, 0.054, 0.062
TEM02 0.083, 0.078, 0.079, 0.071, 0.078
TEM03 0.018, 0.015, 0.013, 0.015, 0.014

  So the mode-matching ratio is

MMR = 86.2 %, 87.3 %, 86.5 %, 86.6 %, 85.5 %

  From FINE 1FSR measurement, peak heights and mode matching ratio is

TEM00 0.921
TEM01 0.031
TEM02 0.078
TEM03 0.014

MMR = 88.2 %

  Assuming each measurement had same error, mode-matching ratio from these 6 values is

MMR = 86.7 +/- 0.3 %  (error in 1 sigma)

  This can be improved by ~5% by alignment because we still see ~5% of TEM01/10. Study in systematic errors on going.

  5790   Wed Nov 2 21:15:06 2011 KatrinUpdateCDSand again c1scy.mdl compiled

I changed an ADC channel for GCY_ERR and thus recompiled the c1scy model.

  8442   Thu Apr 11 03:38:40 2013 DenUpdateLockingangular motion

Spectra of BS, PRM, ITMX, ITMY are attached with oplevs ON and OFF (in units of urad). Loops reduce RMS from ~2urad to ~0.3urad but phase margin should be increased. REF traces show loop OFF. <-- really?

Note how PRM pitch and yaw spectra are different in the frequency range 0.5 - 7 Hz; yaw is factor of 50 larger then pitch at 2 Hz.

Attachment 1: oplevs.pdf
oplevs.pdf oplevs.pdf oplevs.pdf oplevs.pdf
  9653   Wed Feb 19 08:07:01 2014 steveUpdatesafetyannual laser safety glasses check


 All 40m laser safety glasses are cleaned and measured this morning.  Bring your own safety glasses if you have to enter the 40m IFO room.


Glasses were washed in 1% Liquinox water solution and  their transmission measured at  165 mW,  2 mm OD beam of 1064 nm

Attachment 1: AA2014checked.jpg
Attachment 2: 2014check.jpg
ELOG V3.1.3-