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ID Date Author Typedown Category Subject
  9538   Wed Jan 8 13:46:39 2014 JenneUpdateGeneralIFO plan, PRM baffle

Quote:

While we're in there, we need to also put a baffle on the back side of the PRM cage, to protect the OSEMs from stray light.  Den and I discovered before Christmas that turning off the OSEM and OpLev damping to the PRM (while using the POP QPD for ASC) significantly reduced the power fluctuations in the PRC.  We still had arm power fluctuations, but I believe those are likely because our ALS system can't hold an arm precisely at full resonance.  So, putting a black glass baffle with ~2 inch aperture right up against the OSEMs should help a lot.  This week, I'll ask Steve to make me a quickie to-scale cardboard version of the baffles that he has had cut, so I can try securing it to the dirty suspension cage that we have out.  I will also check to make sure I have seen with my own eyes the baffles that I need, and copper wire to tie it to the cage.

Steve may actually be onto something with the clamps that he had made a year and a half ago.  These clamps hold the glass, and then clamp to the base of the suspension cage.  Not the table, but the base of the suspension cage. The drawings are in elog 6344.  I'm not sure that the 1/4-20 holes in the clamp things are exactly where we'll want them, but we should be able to just dog it down to the base of the suspension.  I need to check this, but it may be even easier than tieing the glass to the cage.

Also, something to think about is that the earthquake stop screws extend backwards farther than the OSEMs.  I'm not sure anymore if we have shorter 1/4-20 earthquake stops around (if we do, they should be in the cleanroom shelves), but if we can't swap those out, they'll limit how close we can get to the OSEMs. 

Here's an overhead photo from 6 Sept 2012:

PRMcage_6Sept2012.JPG

  9540   Wed Jan 8 17:53:26 2014 manasaUpdateGeneralIFO plan, IPANG telescope

For the IPANG telescope design, we are in the 'beyond the Rayleigh range' regime. So using a single lens to make the beam small is not a great idea. I have put down a solution where we use a pair of lenses; one of which will be mounted in-vacuum in the ETMY chamber and the other on the endtable.
This way we will also allow have some freedom to configure the layout out-of vacuum in case the need arises. The layout will look something like in the cartoon:
IPANG_layout.png

I also made a choice of using longer focal length lenses (CVI 2" lenses f =1 m). Below is the beam path summary for IPANG telescope. I have used the waist diameter at the ITM for propagation. The endtable is roughly at 41.2m. The QPD will be placed in front of the waist (w0=47um).
IPANG.png 

  9542   Thu Jan 9 10:34:58 2014 SteveUpdatePSLPSL pointing changes in pitch

  IOO QPDs tested in dark, lighted and open PSL enclosure. The created temperature change 0.03 C has  effect on monitoring  in pitch.

 

 Atm1,  all lights off 10 min, PSL enclosure lights on  10 min, all lights off 15 min, open  door # 11 at north east corner of enclosure ( HEPA filters are running at 30V ) for 10 min, closed-dark enclosure 15 min

              dark 10, lighted 10, dark 15, open-dark 10 and closed-dark 15 minutes

 

Atm2, Pitch drift of 24 hours does not recover

Attachment 1: Lfnfdnc.png
Lfnfdnc.png
Attachment 2: 24hPSLpointing.png
24hPSLpointing.png
  9543   Thu Jan 9 17:21:45 2014 ranaUpdateGeneralIFO plan, IPANG telescope

Quote:

For the IPANG telescope design, we are in the 'beyond the Rayleigh range' regime. So using a single lens to make the beam small is not a great idea. I

Can you please explain this? I don't understand what exactly is the issue or 'great idea'.

I think we should be OK with just a single lens in the vacuum. But what we need is the ray tracing analysis to show what the effect will be on the IPANG readout.

  9545   Fri Jan 10 10:28:03 2014 SteveUpdatePSLPSL pointing changes

 

I looked at IOO QPDs again. QPD_POS was clamped by one screw. Dog clamp was added on the unclamped side.

QPD_ANG chassis has no isolation to optical table..._POS has.  QPD_ANG  base was tightened also.

Both QPDs moved a little bit but I did not centered them.  The spot sizes are 2-3 mm  They should be smaller.

How ever, we still can not explane the pitch movement of the IOO beam

 

Razor beam dumps were labeled at the AP table.

 

The 40m roof was cleaned from leafs this morning.

 

 

Attachment 1: clamped.png
clamped.png
  9547   Fri Jan 10 15:33:02 2014 SteveUpdatePSLlaser drift monitor set up idea

this locationQuote:

Quote:

Quote:

I wonder what's drifting between the laser and the PMC? And why is it getting worse lately?

 The PMC refl is bad in pitch today, and the transmission is only 0.76, rather than our usual 0.83ish.

I did a quick, rough tweak-up of the alignment, and now we're at 0.825 in transmission.

 The PMC transmission continuously degrades. In order to see what is really drifting the laser output after PBS was sampled as shown.

 IOO pointing is drifting in pitch. I'd like to use a QPD instead of the paper target to see if the Innolite output is stable. The idea is to move temporarily IOO-QPD_POS to  this location

Attachment 1: 2daysDrift.png
2daysDrift.png
  9549   Mon Jan 13 11:08:48 2014 SteveUpdatePSL3 good days of IOO pointing

 Three good days of IOO pointing: Friday, Sat and Sun    What was changed?  May be the clamping on Friday?

IOO vertical changes recovering as tempeture. IP is clipping at plastic enclosure of ETMY

 

NOTE: ANTS at the PSL optical table.  I will mop with chemicals tomorrow if we see more.

 

Attachment 1: 3gdPSLpointing.png
3gdPSLpointing.png
  9550   Mon Jan 13 16:50:55 2014 SteveUpdateVACMaglev controller needs service

Quote:

 The date is correct on this monitor.

Last stored RGA scan data Dec 20, 2013

IFO pressure at CC1 5.8e-6 Torr

Valve configuration: Vacuum Normal, confirmable only by manual checking of position indicators and pressure gauge controllers  readouts

 

 The Osaka TG390MCAB maglev turbo pump's controller TC010M has passed the 40,000 hrs of operation. This triggered the " alarm" LED  warning light to come on. 

It is normal maintenance.  Maglev TP-1 is running perfectly.  Osaka will send us a loaner-controller that we can use while they do the std maintenance.

I'm thinking of ~ February to do this.

  9552   Tue Jan 14 10:12:12 2014 SteveUpdatePSLlaser drift monitor set up idea

Quote:

this locationQuote:

Quote:

Quote:

I wonder what's drifting between the laser and the PMC? And why is it getting worse lately?

 The PMC refl is bad in pitch today, and the transmission is only 0.76, rather than our usual 0.83ish.

I did a quick, rough tweak-up of the alignment, and now we're at 0.825 in transmission.

 The PMC transmission continuously degrades. In order to see what is really drifting the laser output after PBS was sampled as shown.

 IOO pointing is drifting in pitch. I'd like to use a QPD instead of the paper target to see if the Innolite output is stable. The idea is to move temporarily IOO-QPD_POS to  this location

 I do like to move IOO-QPD_POS temporarily to see that the feedback has anything to do with with the pointing.

Attachment 1: bad4thday.png
bad4thday.png
  9553   Tue Jan 14 10:34:57 2014 SteveUpdatePSLgreen transmission measurment

GariLyn is using our green light on the west side of the PSL table. The green PDA36As were moved and the HEPA turned up to 60V

Attachment 1: greenPickUp.jpg
greenPickUp.jpg
  9556   Wed Jan 15 13:05:30 2014 JenneUpdatePEM4.4 EQ in Fontana, CA

It looks like there was a 4.4 magnitude earthquake near Fontana, CA around 1:30am today.  This tripped all of the suspension watchdogs, which Q has just now re-enabled. 

  9558   Wed Jan 15 18:42:57 2014 JenneUpdateASCPOP ASC QPD offline for a few hours this afternoon

I was in the lab, near the south end of the ITMX oplev table, looking for something, and I bumped the POP ASC QPD's power supply.  I thought that it was fine, but did not adequately check it.  When EricQ asked me just now about why the PRC is so wobbly today, I checked, and the power for the QPD wasn't properly connected (it's kind of a crappy connector, that if you nudge, contacts or loses contact).  Anyhow, I restored power to the QPD, and the PRC looks a little more stable now.  My fault for not checking more carefully, and my apologies to Q and Gabriele for their frustrations this afternoon.

  9559   Thu Jan 16 08:19:29 2014 SteveUpdatePEM4.4 and 3.8M local earth quakes


It looks like there was a 4.4 magnitude earthquake near Fontana, CA around 1:30am today.  This tripped all of the suspension watchdogs, which Q has just now re-enabled. 

   Earth quake shake down yesterday Atm1

Atm2, today's shake

Attachment 1: local4.4eq.png
local4.4eq.png
Attachment 2: local3.8eq.png
local3.8eq.png
  9560   Thu Jan 16 21:38:13 2014 ericqUpdateLSCRepeat of PRC length measurement

[ericq,Jenne]

Since we don't have agreement between the measurements we made the other day and the earlier estimations, I wanted to repeat the demodulation angle measurement. We had to do a few things to keep the PRMI locked, since in the last few days, it hasn't been stable enough.

The mode cleaner had been very fussy lately; the WFS were pushing in a way that caused fast oscillations of the transmission and reflection powers. I turned off the servos, manually aligned the mode cleaner to transmission of about 15k and refl of about .4, centered the beams on the WFS QPDs, and turned the loops back on. Things were much stable after that. Also, Jenne noticed that the PMC loop had walked the laser PZT temperature to a bad place, and fixed it.

After aligning the carrier locked PRMI, the last piece needed to get things stable enough for sideband locking was turning off the angular damping on the PRM suspension screen (this was turned back on when we were done). Waiting until evening noise levels probably helped too. We used a 1000 count MICH excitation in the PRMI case, and recorded data for about a minute in one degree steps around the demodulation phase that looked to put the excitation entirely within the Q of the PD. Also, we notched out the excitation frequency in the MICH servo bank for today's measurement; I think it's outside of the loop bandwidth anyways, but it's good to be sure. 

Jenne and I pondered a bit whether changing the AS55 demodulation phase while it (AS55 Q) is being used as the MICH control signal introduces subtleties that we haven't anticipated, but couldn't come up with anything concrete. Changing the angle from the what maximizes the Q just looks like a slight change in MICH gain, and shouldn't affect the phase of the excitation signal on the PD...

In any case, the data have been recorded, and the results will follow soon. 

  9563   Tue Jan 21 19:41:59 2014 JenneUpdateElectronicsRF distribution box power button fail

Rana, Gabriele and I are trying to measure the FSR of the PRC (elog about that later), and we turned off the power to the RF generation box so that we could switch cables at the EOM combiner.  However, as in elog 9101, the power button won't latch when we try to turn the power back on.  All 3 of us tried, to no avail.  For our measurement, poor Gabriele is standing holding the button pushed in, so that we can have some RF sidebands. 

Tomorrow, we'll have to pull the RF generation box, and put in a better switch.

  9566   Wed Jan 22 16:36:45 2014 ericqUpdateElectronicsRF distribution box power button fail

Quote:

Rana, Gabriele and I are trying to measure the FSR of the PRC (elog about that later), and we turned off the power to the RF generation box so that we could switch cables at the EOM combiner.  However, as in elog 9101, the power button won't latch when we try to turn the power back on.  All 3 of us tried, to no avail.  For our measurement, poor Gabriele is standing holding the button pushed in, so that we can have some RF sidebands. 

Tomorrow, we'll have to pull the RF generation box, and put in a better switch.

I replaced the stupid broken fancy button with a simple sturdy switch. I had to file out the hole in the chassis a bit, but the switch is pressed in tightly and securely. I put the box back in the rack, but the power cable was coming directly from the power supplies with no fuses. The box was drawing ~.9 and 1.5 Amps from two supplies, so I put 2A fuses on both. Plugged everything back in, and the mode cleaner locks, so it looks like all is well.

RXA: When its so close, I prefer to size it up by 1 step. Please change to 5A fuses. Otherwise, we may blow them from power glitches.

Q: 5A fuses have been swapped in

  9567   Wed Jan 22 18:17:46 2014 JenneUpdateCDSfb timing was off

Since this morning, the fb's timing has been off.  Steve pointed it out to me earlier today, but I didn't have a chance to look at it until now. 

This was different from the more common problem of the mx stream needing to be restarted - that causes 3 red blocks per core, on all cores on a computer, but it doesn't have to be every computer.  This was only one red block per core in the CDS FE status screen, but it was on every core on every computer. 

The error message, when you click into the details of a single core, was 0x4000.  I elog searched for that, and found elog 6920, which says that this is a timing issue with the frame builder.  Since Jamie had already set things on nodus' config correctly, all I did was reconnect the fb to the ntp: 

fb$ sudo /etc/init.d/ntp-client restart

As in elog 6920, the daqd stopped, then restarted itself, and cleared the error message. It looks like everything is good again.

I suspect (without proof) that this may have to do with the campus network being down this morning, so the computers couldn't sync up with the outside world.

  9568   Wed Jan 22 20:00:41 2014 JenneUpdateGeneralVENT GO!

Steve, please begin the vent!!

[EricQ, Jenne]

We have followed the pre-vent checklist, and done everything except check the jam nuts (which Steve can do in the morning).

We are ready to vent, so Steve, please begin bringing us up to atmosphere first thing in the morning.

Here is a copy of the list, from the wiki:

 

 

  • Center all oplevs/IPPOS/IPANG
  • Align the arm cavities for IR and align the green lasers to the arms. (Green powers were both ~0.8.  We only touched the Xend PZTs remotely, did not touch Yend).
  • Make a record of the MC pointing
  • Align the beam at the PSL angle and position QPDs (Did not need doing, left QPDs as-is so we keep our long-term trend.)
  • Reduce input power by touching wave plate on the PSL table BEFORE THE PMC.  (HWP was at 269degrees, now at 3 hundred something to make power just before PSL shutter 90mW)
  • Replace 10% BS before MC REFL PD with Y1 mirror and lock MC at low power.
  • Close shutter of PSL-IR and green shutters at the ends
  • Make sure the jam nuts are protecting bellows
  •  

     

    Attachment 1: IFOstatus_lowPower_preVent.png
    IFOstatus_lowPower_preVent.png
      9570   Thu Jan 23 08:04:04 2014 SteveUpdateVACvacuum control screen is blank

     

    There is BLANK VacControl_BAK.adl screen only. 

    I can move a valve by disconnecting it's  solenoid power if it's position is normally open.

    I will close V1 and check computer cable connections and move on with manual - hand disconnect ea valve to be moved into the right position for vent. Valve positions will be confirmed by looking manual indicators on valves.

    Attachment 1: pd76m170d2dRgaOn.png
    pd76m170d2dRgaOn.png
      9571   Thu Jan 23 13:23:10 2014 SteveUpdateVAC40m IFO is at atmosphere

    Quote:

     

    There is BLANK VacControl_BAK.adl screen only. 

    I can move a valve by disconnecting it's  solenoid power if it's position is normally open.

    I will close V1 and check computer cable connections and move on with manual - hand disconnect ea valve to be moved into the right position for vent. Valve positions will be confirmed by looking manual indicators on valves.

     The 40m vacuum envelope vent is completed with instrument grade air.

    Valve configuration: chamber open, RGA is pumped through VM3 by TP3,

      9572   Thu Jan 23 23:10:19 2014 ericq UpdateGeneralVent so far

    [ericq, Manasa, Jenne]

    Summary: We opened up the BS and both ITM chambers today, and put the light doors on. //Edit : Manasa  Post-vent the MC was very much misaligned in yaw. Both the ITMs moved in pitch as inferred from the oplev; but there is still light on the oplev PDs//. We toiled with the PMC and mode cleaner for a while to get reasonable transmission and stability (at least for a period of time). We then tried to lock IR to the y-arm, to no avail. 

    Locking the PMC doesn't seem very robust with the low power level we have; adjusting the gain at all when it's locked throws it right out. The mode cleaner spot was visibly moving around on MC2 as well. We'll continue tomorrow. 

    Details about alignment efforts: Manasa and I tried for a while to try and align the y-arm for IR. Straight out of venting the green TM00 would lock to the y-arm with about .45, as compared to .8 before venting, so it didn't seem to drift too far. The x-arm would even flash any modes, however. For a while, IR was no where to be seen after the mode cleaner. Eventually, we used the tip tilts to bring the AS beam onto the camera, which exhibited fringes, so we knew we were hitting the ITMs somewhere. We wandered around with the ETM to see if any retroflection was happening, and saw the IR beam scatter off of the earthquake stop. We moved it to the side to see it hitting the OSEM holder, and moved down to the bottom OSEM holder to get an idea of where to put pitch to get roughly the center of the ITM, then undid the yaw motion.

    There, we would see very infrequent, weak flashes. We weren't able to distinguish the mode shape though; however, the flashes were coincident with where the green would lock to a very yaw-misaligned fishbone mode, to the lower right of the optic's center. We figured that if we gradually fixed the green alignment with the mode shapes we could see and actually lock on, we could use the tip tilts to adjust the IR pointing and keep it coincident and eventually resonate more. However, this didn't really work out. The flashes were very infrequent, and at this point the PMC/MC were getting very touchy, and would cease to stay locked for more than a minute or two. At this point, we stopped for the day. 

     

      9576   Mon Jan 27 09:08:00 2014 SteveUpdateVAC4 days at atmosphere

     

     

    Attachment 1: day4atm.png
    day4atm.png
    Attachment 2: vent76bgTp3d4.png
    vent76bgTp3d4.png
      9577   Mon Jan 27 12:26:00 2014 KojiUpdateIOOIOO Slow Actuator Servo threshold changed

    In order to activate the slow actuator servo for the MC locking,
    the threshold level for this servo (C1:PSL-FSS_LOCKEDLEVEL) was changed from 10000 to 700.

    Now the servo started to move the PZT fast out to be controlled to 5V.

      9579   Mon Jan 27 21:36:35 2014 ericq UpdateGeneralVent so far

    After turning the slow FSS threshold down, the mode cleaner stays locked enough to do other things. We were able to align the tip tilts to the y-arm such that we were able to get some flashes in what looks like a TM00-ish mode. (It was necessary to align the PRM such that there was some extra power circulating in the PRC to be able to see the IR flashes on the ITMY face camera) This is enough to convince us that we are at least near a reasonable alignment, even though we couldn't lock to the mode. 

    The x-arm was in a hairier situation; since the green beam wouldn't flash into any modes, we don't even know that a good cavity axis exists. So, I used the green input PZTs to shine the green beam directly on the earthquake stops on the ITMX cage, and then inferred the PZT coordinates that would place the green beam roughly on the center of ITMX. I moved the ETMX face camera such that it points at the ETMX baffle. I tried looking for the retroreflected green spot to no avail. Hopefully tomorrow, we can get ourselves to a reasonably aligned state, so we can begin measuring the macroscopic PRC length. 

      9580   Tue Jan 28 09:51:47 2014 SteveUpdateIOOlow power pointing

     

    PSL output is stable.

    Attachment 1: IOO4dlowpr.png
    IOO4dlowpr.png
      9581   Tue Jan 28 11:13:50 2014 KojiUpdateVAC vacuum monitor is still blank

    [Steve Koji]

    We pushed the reset button of c1vac1 and c1vac2 and the vacuum screen is back.

    First, we pushed the reset button of c1vac1 and pushed the one on c1vac2.
    This did not bring c1vac2 up. We pushed the reset of c1vac2 again and now everything of the vacuum screen is back.

      9582   Tue Jan 28 16:26:40 2014 SteveUpdateVAC vacuum computers are back without safety

    Quote:

    [Steve Koji]

    We pushed the reset button of c1vac1 and c1vac2 and the vacuum screen is back.

    First, we pushed the reset button of c1vac1 and pushed the one on c1vac2.
    This did not bring c1vac2 up. We pushed the reset of c1vac2 again and now everything of the vacuum screen is back.

     1, Reset works

     2, Default values are lost. They actually reversed into open and turn on everything when power recycle c1vac1, c1vac2 or 24V dc power supply. This can vent the IFO in an event of power failure!

          It's may be the time to go back to an isolated, vacuum controller only computer.

     

    The present valve configuration at Atm1

    a, all annuloses are vented

    b, valve cables disconnected at: VC1 and 4 IP gate valves

    c, the RGA is off and it is pumped by the Maglev through VM2

    d, cryo pump is being roughed with TP3  It's outgassing rate was 25 mTorr / min

    e, Roughing hose is disconnected

    Attachment 1: c1vac1_vac2areback.png
    c1vac1_vac2areback.png
      9583   Tue Jan 28 22:24:46 2014 ericq UpdateGeneralFurther Alignment

    [Masasa, ericq]

    Having no luck doing things remotely, we went into the ITMX chamber and roughly aligned the IR beam. Using the little sliding alignment target, we moved the BS to get the IR beam centered on ITMX, then moved ITMX to get good michelson fringes with ITMY. Using an IR card, found the retroflection and moved ETMX to make it overlap with the beam transmitted through the ITM. With the PRM flashing, X-arm cavity flashes could be seen. So, at that point, both the y-arm and x-arm were flashing low order modes. 

      9584   Tue Jan 28 23:32:12 2014 KojiUpdateGeneralX/Y arm locked with the IR beam

    [Koji EricQ]

    The both arms have been locked with IR and aligned by ASS.

    The IFO was left with ITMX/Y, ETMX/Y, BS, and PRM aligned, and the PSL shutter closed.


    YARM
    SIGNAL PATH:
    POY11I(+45dB)->YARM(G=+1.0)->ETMY
    NORM: TRYx10
    TRIG: TRY 0.01up/0.005down
    FM TRIG: FM2/3/6/7/8/9 0.01up/0.05down, 0.5 sec delay

    XARM
    SIGNAL PATH:
    POX11I(+45dB)->XARM(G=+4.0)->ETMX
    NORM: TRXx10
    TRIG: TRX 0.01up/0.005down
    FM TRIG: FM2/3/6/7/8/9 0.01up/0.05down, 0.5 sec delay


    For decent locks, it was necessary that the offset of the error signals are trimmed at the input filters
    even after running LSCoffset.py script.

    Once the cavities were aligned for the IR, we could see the green beams are also flashing.
    The Y arm was actually locked with the green with a TEM00 mode

    Attachment 1: good_alignment.png
    good_alignment.png
      9587   Thu Jan 30 11:59:03 2014 manasaUpdateCDSfb timing was off

    Quote:

    Since this morning, the fb's timing has been off.  Steve pointed it out to me earlier today, but I didn't have a chance to look at it until now. 

    This was different from the more common problem of the mx stream needing to be restarted - that causes 3 red blocks per core, on all cores on a computer, but it doesn't have to be every computer.  This was only one red block per core in the CDS FE status screen, but it was on every core on every computer. 

    The error message, when you click into the details of a single core, was 0x4000.  I elog searched for that, and found elog 6920, which says that this is a timing issue with the frame builder.  Since Jamie had already set things on nodus' config correctly, all I did was reconnect the fb to the ntp: 

    fb$ sudo /etc/init.d/ntp-client restart

    As in elog 6920, the daqd stopped, then restarted itself, and cleared the error message. It looks like everything is good again.

    I suspect (without proof) that this may have to do with the campus network being down this morning, so the computers couldn't sync up with the outside world.

    The above timing problem has been repeating (a couple of times this week so far). It does not seem to be related to the campus network.

    The same solution was applied.

      9589   Fri Jan 31 18:41:25 2014 manasaUpdateGeneralIFO alignment update

    [EricQ, Gabriele, Manasa]

    We found we had lost the Y arm pointing from yesterday. We tried to recover the pointing for a couple of hours and finally decided to take the ETMY heavy door off.

    The input beam was aligned to the Y arm. We also got AS and REFL out of vacuum and on the cameras.

    We put back the light doors and tried to lock the arms, but did not succeed as yet.

    Things to do:
    1. Lock arms for IR
    2. Realign POP path
    3. Recenter all oplevs
    4. Try to check the state of PRC after the length change
    5. Take in-vacuum pictures

      9591   Mon Feb 3 10:17:14 2014 SteveUpdatePEMdusty surfaces

    Please wet WIPE before opening chamber or optical table ! ! 

     with methanol soaked kimwipes.

    The Met One particle counter is located on CES wall, just behind ITMX chamber. 

    The numbers are not so bad, but have you ( ...a)  asked the IFO lately?

    Attachment 1: AP-ISCT.jpg
    AP-ISCT.jpg
    Attachment 2: BSC-rim.jpg
    BSC-rim.jpg
    Attachment 3: ITMX-ISCT.jpg
    ITMX-ISCT.jpg
    Attachment 4: 12daysAtm.png
    12daysAtm.png
      9592   Mon Feb 3 15:57:52 2014 SteveUpdateGreen LockingETMX green power

    There was 0.2 mW green at the X end.

    The doubling oven temp was changed from 37.5 to 36 degrees C

    Power at green shutter 3 mW  The alignment was not touched.

    Attachment 1: ETMXgreen.jpg
    ETMXgreen.jpg
    Attachment 2: XgreenOven36C.jpg
    XgreenOven36C.jpg
      9593   Mon Feb 3 23:31:33 2014 ManasaUpdateGeneralAlignment update / Y arm locked

    [EricQ, Manasa, Koji]

    We measured the spot positions on the MC mirrors and redid the MC alignment by only touching the MC mirror sliders. Now all the MC spots are <1mm away from the center.

    We opened the ITMY and ETMY chambers to align the green to the arm. The green was already centered on the ITMY. We went back and forth to recenter the green on the ETMY and ITMY (This was done by moving the test masses in pitch and yaw only without touching the green pointing) until we saw green flashes in higher order modes. At this point we found the IR was also centered on the ETMY and a little low in pitch on ITMY. But we could see IR flashes on the ITMYF camera. We put back the light doors and did the rest of the alignment using the pitch and yaw sliders.

    When the flashes were as high as 0.05, we started seeing small lock stretches. Playing around with the gain and tweaking the alignment, we could lock the Y arm in TEM00 for IR and also run the ASS. The green also locked to the arm in 00 mode at this point. We aligned the BS to get a good AS view on the camera. ITMX was tweaked to get good michelson.

      9594   Tue Feb 4 00:42:18 2014 KojiUpdateGeneralX arm aligned for IR/GR

    The X arm was also aligned for the IR by hand and ASS. Also the X end green PZT was aligned to make the TEM00 mode reasonably locked.

    What I did:

    - Looked at the ITMXF camera. It seemed that the green beam was hitting the mirror.

    - Went to the end. Looked at the X end green REFL. Tuned coarse alignment of the ETMX so that the beam was (retro-)reflected to the Faraday and the REFL PD.

    - Looked at the ETMX face from the view port. Tried to locate the spot from the ITMX by shaking the ITMX alignment with 0.1 and then 0.01 increments.

    - After some struggle with the ETMX and ITMX alignment, resonant fringes were found on the ETMY face while I still looked at the ETMX.

    - Once the ITMX/ETMX were aligned, the BS needed to be aligned. But of course there was no IR fringe.

    - Returned to the original alignment of the ITMX to find the ITMX spot on the AS camera.
    Then gradually moved the ITMX to the aligned value for the green while tracking the michelson alignment with the BS.
    This made the AS spots at the upper left edge of the AS video image.

    - This was enough to find the IR spikes at TRX. Then the ETMX was touched to maximize the transmission.

    - Lock the cavity. Use the ASS to optimize the alignement.

    - Once the arm mirrors were aligned, the Xend PZT was also adjusted to have TEM00 for the green beam.


    Now I leave the IFO with ITMX/Y, ETMX/Y and BS aligned. As I wrote above, the AS spot is very high at the AS camera.
    We need to revisit the AS steering (SR TTs?) to ensure the AS beam unclipped.

      9595   Tue Feb 4 01:02:03 2014 KojiUpdateGreen LockingETMX green power

    Manasa, Steve: Please revisit the Xend oven temperature again.


    I found that the X end SLOW control was left on for ~15days. The output of the filter had grown to ~2e7.

    This yielded the laser temperature pulled with the maximum output of the DAC.

    This was the cause of the power reduction of the X end SHG; phase matching condition was changes as the wavelength of the IR was changed.

    Once the SLOW output was reset, the green REFL was reduced from 4000cnt to 1800cnt.

    Attachment 1: Screenshot-Untitled_Window.png
    Screenshot-Untitled_Window.png
      9596   Tue Feb 4 16:43:50 2014 manasaUpdateGeneralIFO alignment update

    [EricQ, Manasa]

    We are close to the end of the vent except for a couple of issues.

    * POP is not visible on the IR card. But we see POP flashes unclipped on the camera and also spikes in POP DC. So  we are assuming that the POP path hasn't gone far off. If anybody has suggestions for a better method to check this, we could give it a try.

    * PRM suspension has not been behaving well. PRM is being kicked around every 5-10 seconds when the PRC is aligned (as seen on REFL camera). We are not sure where this is coming from. The first time we saw this happening was when we were trying to lock PRC at low power even before we took the heavy doors off. So we are pretty sure this is not caused by the foil cover on the OSEMs. We tried turning ON/OFF the oplev servo, turning ON/OFF the damping loops and also checked the connections in the feedthrough and satellite box for the PRM. The OSEM sensor values for the suspension also seem to match the ones on the wiki.

     

    Closeup checklist

     

    • Center beam on all AS optics
    • GET CAMERA IMAGES OF EVERYTHING

      • We must get images right before closing, right after closing, etc.
    • Make sure REFL is clear
      • dither PRM, see motion on AP tables
    • Make sure AS is clear
      • dither BS/ITM, see motion on AP tables
    • Using IPANG/POS pick-off mirrors, center beams on:
      • IPPOS
      • IPANG (IPANG aligned to be low in pitch. The beam comes out of vacuum unclipped and hits the first steering mirror outside vacuum at its lower edge)
    • Check green alignment in the arms and make sure the transmitted green reaches the PSL table.
    • Check all OpLevs centered, in and out of vacuum

    • Close PSL shutter & green shutters at the ends

    • Check jam nuts
      9597   Tue Feb 4 17:40:19 2014 manasaUpdateGeneralReady for pump down??

    Quote:

    * PRM suspension has not been behaving well. PRM is being kicked around every 5-10 seconds when the PRC is aligned (as seen on REFL camera). We are not sure where this is coming from. The first time we saw this happening was when we were trying to lock PRC at low power even before we took the heavy doors off. So we are pretty sure this is not caused by the foil cover on the OSEMs. We tried turning ON/OFF the oplev servo, turning ON/OFF the damping loops and also checked the connections in the feedthrough and satellite box for the PRM. The OSEM sensor values for the suspension also seem to match the ones on the wiki.

     

    This is solved.

    The ASC for PRC for left turned ON. Turning it OFF solved the problem.

    If there is no feedback regarding the POP alignment or anything to check with modified PRC length, we will close tomorrow morning.

      9598   Tue Feb 4 23:01:24 2014 JenneUpdateGeneralReady for pump down??

     

     This sounds great! The only suggestion that I have is for checking POP. If you have the beam on the camera, you can hold a card in front of each mirror, and find out where the edge of the beam is. Introduce the card from the side, and watch for the point where you just start to see the beam on the camera be obstructed. Repeat for the other side, and you have an idea of the centering of the beam. 

    I think this is most important for the in-vac mirrors, since the beam is large-ish, and we have to hit both steering mirrors at ~45 degrees.

      9599   Wed Feb 5 08:14:59 2014 SteveUpdateVAC vacuum computers are back without safety

    Quote:

     

     1, Reset works

     2, Default values are lost. They actually reversed into open and turn on everything when power recycle c1vac1, c1vac2 or 24V dc power supply. This can vent the IFO in an event of power failure!

          It's may be the time to go back to an isolated, vacuum controller only computer.

     

    The present valve configuration at Atm1

    a, all annuloses are vented

    b, valve cables disconnected at: VC1 and 4 IP gate valves

    c, the RGA is off and it is pumped by the Maglev through VM2

    d, cryo pump is being roughed with TP3  It's outgassing rate was 25 mTorr / min

    e, Roughing hose is disconnected

     Vacuum checks before pump down:

    1, check intermittent contact issue in black relay box

    2, reconnect cable to ion pumps and vent them to atm before pump down

    3, repeat power shutdown-reboot at atmosphere

      9600   Wed Feb 5 09:28:32 2014 SteveUpdateSUSETMY damping restored

    ETMY damping restored.

      9601   Wed Feb 5 15:26:57 2014 manasaUpdateGeneralReady for pump down??

    Quote:

     

     This sounds great! The only suggestion that I have is for checking POP. If you have the beam on the camera, you can hold a card in front of each mirror, and find out where the edge of the beam is. Introduce the card from the side, and watch for the point where you just start to see the beam on the camera be obstructed. Repeat for the other side, and you have an idea of the centering of the beam. 

    I think this is most important for the in-vac mirrors, since the beam is large-ish, and we have to hit both steering mirrors at ~45 degrees.

     [EricQ, Manasa]

    This check was done and we had to move one of the steering mirrors in pitch. Else, everything was just fine.

    In-vacuum pictures of PR2 and PR3 new positions were taken. MC spot positions measured to be < 1mm and oplevs were centered.

      9602   Wed Feb 5 15:39:41 2014 manasaUpdateGeneralWe are pumping down

    [Steve, Manasa]

    I checked the alignment one last time. The arms locked, PRM aligned, oplevs centered.

    We went ahead and put the heavy doors ON. Steve is pumping down now!

    Attachment 1: pre_pump_down.png
    pre_pump_down.png
      9604   Wed Feb 5 19:36:50 2014 SteveUpdateVACpumpdown at 25 Torr

    Quote:

    [Steve, Manasa]

    I checked the alignment one last time. The arms locked, PRM aligned, oplevs centered.

    We went ahead and put the heavy doors ON. Steve is pumping down now!

     The ion pumps were vented just before pumpdown and their gate valves were opened.

    This is an effort to minimize a possible leak through their gates.

    Is there a volunteer who goes home late and would close off the roughing? tonight

    Attachment 1: pd77at3.5h.png
    pd77at3.5h.png
      9605   Wed Feb 5 19:53:51 2014 SteveUpdateVACpumpdown stops for the day at 14 Torr

     

     

    Attachment 1: stopHere.png
    stopHere.png
      9606   Wed Feb 5 20:41:57 2014 DenUpdateLSCcalibrated spetra from OAF test

    We did online adaptive filtering test with IMC and arms 1 year ago (log 7771). In the 40m presentations I can still see the plot with uncalibrated control spectra that was attached to that log. Now it the time to attach the calibrated one.

    Template is in the /users/den/oaf

    Attachment 1: oaf_cal.pdf
    oaf_cal.pdf
      9607   Thu Feb 6 11:14:07 2014 SteveUpdateVACpumpdown completed

     Pumpdown completed. IR shutter opened at P1 1 mTorr  The block is still in the beam path.

    Remember to protect MCR pd before crack up the PSL power.

    The ion pump gate valves were just closed by cc1 triggered interlock

    The cry pump was "regenerated" during the vent and it's outgassing rate minimized.

    CC3 cold cathode gauge was replaced.

     

    Valve configuration for week end:

    1, VA6 disconnected to avoid accidental venting the IFO through the annulos

    2, VC2 disconnected to insure that the cryo stays closed

    3, RGA is not running, It's pressure limit 1e-5 Torr

     

    Attachment 1: pd77.png
    pd77.png
      9608   Thu Feb 6 16:41:31 2014 ericqUpdateGeneralIn-Vac Alignment

    [Manasa, ericq]

    Both arms have been aligned via ASS. PRC locked on carrier.

    SB locking hasn't happened yet...

    Details:

    • Aligned MC at low power, measured spots
    • Found ITMX AS, REFL spots on cameras. Couldn't find ITMY spot. Found x-arm flashes with PRM aligned.
    • MC Refl Y1 mirror was replaced with the 90:10 BS; blocked WFS path until MC was aligned
    • PMC power was increased (~1.4W directly before PSL shutter)
    • Touched up MC alignment, reactivated high power autolocker, measured spots.
    • Locked x-arm on IR, ran ASS
    • Found ITMY spot on AS camera, locked y-arm, ran ASS on both arms
    • Checked green beams. Y-arm locks at around .6, X-arm at around .2 (input steering needs adjustment)
    • Centered beams on WFS, reset filter bank offsets, turned on WFS
    • Aligned PRM, locked PRC on carrier.
    • Tried locking PRC on sideband, had troubles. Looks like there is some increased seismic activity; might be the culprit.

     

      9609   Fri Feb 7 12:43:12 2014 ericqUpdateGeneralIn-Vac Alignment

    [ericq]

    PRC Locked on Sidebands

    Jenne reminded me that if we change a cavity, phases can change... So, first, I locked the PRC on the carrier, and then gave it MICH and PRCL excitations to optimize the AS55 and REFL55 phase rotation angles by looking at the excitation demodulated outputs of the unused quadrature (i.e. we want all of MICH to be in AS55 Q, so I rotated the phase until C1:CAL-SENSMAT_MICH_AS55_I_I_OUTPUT was zero on average).

    This resulted in:

    • AS55: 7 -> -5.5
    • REFL55: 73 -> 86.9

    I then used the same settings as in ELOG 9554, except I used -1s instead of +1s for the POP110I trigger matrix elements. (I'm not sure why this is different, but I noticed that the PRC would lock on carrier with positive entries here, so I figured we wanted the peaks with opposite sign).

    So far, it seems more stable than when we were doing the demodulation phase measurements, it's been locked for >15 minutes without me having to tweak the gains or the alignment from the carrier locked case.

      9610   Fri Feb 7 13:00:52 2014 JenneUpdateGeneralIn-Vac Alignment

    Quote:

    I then used the same settings as in ELOG 9554, except I used -1s instead of +1s for the POP110I trigger matrix elements. (I'm not sure why this is different, but I noticed that the PRC would lock on carrier with positive entries here, so I figured we wanted the peaks with opposite sign).

     Nice work!!  As with all the other RF PDs, POP110's phase likely needs tuning.  You want POP110 (and POP22) I-quadratures to be maximally positive when you're locked on sidebands, and maximally negative when locked on carrier.  What you can do to get close is lock PRC on carrier, then rotate the POP phases until you get maximally negative numbers.  Then, when locked on sideband, you can tweak the phases a little, if need be.

    ELOG V3.1.3-