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ID Date Authorup Type Category Subject
  5037   Tue Jul 26 11:38:45 2011 steveUpdateSUSETMY bias checked

 

 I test drove ETMY biases.

PITCH  worked well in slow and fast modes. Slow drive was from the IFO alignment screen C1:SUS-ETMY_PIT_COM and

the fast one from C1:SUS-ETMY_ASCPIT_OFFSET

YAW did not.  It was always diagonal. It was  specially bad with the fast drive. I compared them with ETMX. ETMX yaw is diagonal a little bit too.

The OPLEV return spots on the qpd ETMX and ETMY are big 5-6 mm diameter. The ETMY spot has weird geometry to qpd.

  5043   Wed Jul 27 10:10:12 2011 steveUpdatePSLlocking status

 80 days: PMC is drifting

Attachment 1: 80dpmcMC.jpg
80dpmcMC.jpg
  5047   Wed Jul 27 15:38:01 2011 steveUpdateVACbeam traps for vacuum

We have cleaned, baked, rga scaned traps for vacuum. Thorlabs LB1 on 1" OD ss posts and forks. The effective surface area is 43 x 18 mm of stacked razors.

Seven pieces are mounted on New Focus #9962  1" OD SS vented-  pedestrals to 5.5" center height and 5 pieces to 4.875"

Attachment 1: P1080095.JPG
P1080095.JPG
  5050   Wed Jul 27 15:49:56 2011 steveUpdateSAFETYManuel receives safety training

Our surf student Manuel Marchiò received 40m specific safety training today.

Attachment 1: P1080096.JPG
P1080096.JPG
  5055   Thu Jul 28 16:26:42 2011 steveUpdateSUSITMX, ITMY & ETMY OSEM gains adjusted

 

OSEM damping gains were adjusted by observing  real time dataviewer to get Q of 5

OSEMs were kicked up one by one with 200 counts  ~1sec. The error signal was optimized to get 1/2 of exitation amplitude at the 5th sinusoid wave.

C1: SUS-ITMX_SUSPOS_N1 gain   111      ->        65,             PIT        7.2      ->    8,           YAW        12      ->     6,          SIDE     280

                  ITMY                                      277       ->     120,                        19.2     ->     7,                             24     ->     19,                        420    ->      470

                  ETMY                                       10        ->       32,                          20      ->     3,                             20     ->     10,                          50

                  ETMX                                       22        ->      25,                             3,                                                3,                                              -170  

ETMX having problems:  1, YAW can not be excited

                                             2, SIDE has no error signal in dataviewer. Sensing voltage on MEDM screen 0.142V

 

                      

 

  5061   Fri Jul 29 16:04:51 2011 steveUpdateSUSETMX, PRM & SRM OSEM gains set

Jamei fixed the computer. Now I had a healthier ETMX with SIDE signal that allowed me to set gains to get Q of 5

The Y arm restore locked the arm at TRY -out 2.4V,    the X arm still did not lock or align to lock. It has some fringes.

ETMX  POS gain   22  -> 17,              PIT  3  ->  1,                    YAW  3,                     SIDE     -170    ->    -110

PRM                        50  ->  30,                     1,                                       2,                                       50

SRM                        55  ->  20,                    2.4  ->  1.5,                      4.8  ->  2,                          140   ->    100

Now all SUS OSEM gains are set

  5080   Mon Aug 1 08:52:37 2011 steveUpdateVACpreparation to vent

Both arms locked easely around 1V transmited.  We should recenter oplevs.

Attachment 1: pztsteering.png
pztsteering.png
Attachment 2: vac1Aug2011.png
vac1Aug2011.png
Attachment 3: PEM200d.jpg
PEM200d.jpg
  5082   Mon Aug 1 16:06:05 2011 steveUpdateSUSoplevs are centered

Kiwamu, Koji and Steve,

Arm aligned separatly and oplev qpds were centered  including BS. Than we realigned manually DRM and centered their qpds.

ALL SUS oplevs were centered to resonating cavities.

  5083   Mon Aug 1 17:47:37 2011 steveUpdateASCwhat is not working

SUS-ETMY_QPD is not responding. It is reading zero in dataviewer and 4,400 counts on QPD MEDM screen.......must be wrong cable connected

IP-POS is sick. Last time alive 7-19-2011

IP-ANG beam is clipping on pick-up mirror at ETMY chamber. This will have to be fixed at the vent. The qpd itself is responding to light.

  5104   Wed Aug 3 09:40:13 2011 steveUpdateVACvent

The vacuum system is coming up to atm. The vent was started with slow N2 flow. The PSL output is blocked 2 places on the table.

Attachment 1: pzt2011Aug3.png
pzt2011Aug3.png
  5109   Wed Aug 3 14:20:49 2011 steveUpdateSUSITMX and PRM damping restored

ITMX watchdog tripped around 5 Torr  and the PRM around 450 Torr of this vent. They were restored than.

We are at 580 Torr now.

  5111   Wed Aug 3 16:18:30 2011 steveUpdateVACvent is almost finished

P1 at 750 Torr,  Vent valve VV1 is left open to atm. It will reach equilibrium in an hour. The PSL power is not turned down yet. The beam path is blocked at two places inside the enclosure.

The low power 20 mW  input  MC can be locked tonight.

 

Next day's - Thursday notes:

We  reached 760 Torr of atm in 8 hrs at  1.7 Torr/ min with 5 cylinders of  instrument grade air.

Used 500 PSI of nitrogen to get to 20 Torr at first.  This flow  and the first cylinder of N2  has to be slower next time.

 

We did the following:

1, oplevs were centered on locked caveties 2 days ago

2, just before vent we rechecked arms  pointing, they wre still locking

3,eloged strain gages  and turned HVs off at PZT-steering   at 1Y3 rack and OMC-PZT ps at 1X2 aux rack. They were actually off.

4,,checked jam nuts 6 places x 3

5, turned oplev servos off

6, eloged SUS summery page

7, checked particle counts at ITMY: 1 micron 300,  0.5 micron 3K,  0.3 micron  30K particles / cft-min. All three cranes were wiped 2 days ago.

8, blocked laser into IFO: main 1064 in 1.25W were blocked by manual 2 blocks on PSL table. The PSL output shutter was left open to be triggered by interlock  at P1 3 mTorr. It did!

    Aux NPRO-AP and green light  input at both ends were blocked.

Attachment 1: vent8h.jpg
vent8h.jpg
  5116   Thu Aug 4 08:25:51 2011 steveUpdateSUSsus at atm

ITMX and PRM moved alot.  BS and   ITMY just a little based on oplev reference.

Attachment 1: SUSatm.png
SUSatm.png
Attachment 2: oplevsaftervent.png
oplevsaftervent.png
  5123   Fri Aug 5 13:51:51 2011 steveUpdateSUScross coupling

We need a plan how to minimize cross coupling in the OSEMs now

  5124   Fri Aug 5 14:03:12 2011 steveUpdateGeneralmalfunctioning crane at ETMY

The horizontal trolley drive stopped working  at the east end this morning. It is working intermittently. In the worst case we can take the door off with the manual -Genie- lift.

I'm working with Konecrane to solve  the wormgear drive problem.

  5139   Mon Aug 8 13:24:00 2011 steveMetaphysicsTreasure Monday morning

Quote:

Just a reminder that a film crew will be here Monday morning, filming Christian Ott for some Discovery channel show.

They are slated to be here from 8am to 12:30pm or so.  They will take a couple of shots inside the lab, and the rest of the filming should be of Christian in the control room (which they will "clean up" and fit with "sexy lighting").  I will try to be here the whole time to oversee everything.

Konecrane Fred was early this morning. He diagnosed the ETMY crane horizontal drive gear box dead and left just before the film crew showed up.

New gear box should be here by the end of this week for installation.

The lab air quality is high ~20,000 counts of particles of 0.5 micron.  Keep an eye on this before you open the chamber.

Attachment 1: P1080147.JPG
P1080147.JPG
  5140   Mon Aug 8 14:21:03 2011 steveUpdatePEMParticle counts controlled

Quote:

[Jenne, Kiwamu]

While Kiwamu was finalizing the X green alignment, I started to prepare to remove the ETMY door, and begin checking out its OSEMs, etc, so we could start moving it to it's new place, and figure out why it's been wonky for a while.  I ran the particle counter, and we have a factor of ~5 more particles than normal.  Kiwamu and I agreed not to open ETMY.  Since we had briefly opened the IOO and Output Optics chambers to check the X green's position on the PSL table, we immediately shut those doors.  They were probably open for ~15 minutes or so.  (Yes Steve, we should have checked before opening any doors, but at least we remembered to check at all, and the doors were only open for a few minutes rather than for a few hours.)

I attach a 24hrs trend of the particle counts, for reference.  It looks like it's been a little high for a while, but today it's really dirty in the air.

 The east end particle count is 155K for 0.3 micron and 15K for 0.5 micron  counts/cf min.  In order to minimize diffusion of dirt into the IFO we set up the mobile HEPA with CP Stat 100 tent.

This set up gives us practically ZERO inside the tent

Attachment 1: P1080149.JPG
P1080149.JPG
Attachment 2: P1080150.JPG
P1080150.JPG
  5142   Mon Aug 8 15:52:39 2011 steveUpdateVACback ground rga scan

The RGA region is beeing monitored during the vent. This will tell us how clean the RGA itself is.

 

Attachment 1: bg-d5.jpg
bg-d5.jpg
Attachment 2: presBg-d5.jpg
presBg-d5.jpg
  5158   Tue Aug 9 16:40:12 2011 steveUpdateGeneralclean room coat counts

I measured the particles coming off of new- unused clean room coat. Tyvek, Convertors, Allegiance #9393 measured  10 counts of 0.3 micron at 1 minute and 0 count at 7 minute.

The 0.5 micron size  measured 0 at both times. Jenne's used coat measured 20 counts of 0.3 micron  and 0 counts for 0.5 micron at 1 minute. ( counts / cf- min)

The HEPA tent background is consistently 0 when it's CP STAT 100 curtains are closed.

Attachment 1: P1080155.JPG
P1080155.JPG
  5159   Tue Aug 9 16:54:47 2011 steveUpdateVACscratch on vac door

Jenne found a big scratch on the north vac door of ITMY. Fortunately it does not reach the inner annulos 0 -ring seal.

This is precisely what we have to avoid to preserve our vacuum system!

 

Attachment 1: P1080152.JPG
P1080152.JPG
  5166   Wed Aug 10 07:59:33 2011 steveUpdateSUSthis is too dam nice

Quote:

Suresh and I tweaked the OSEM angles in ETMX yesterday.  Last night the ETMs were left free swinging, and today I ran Rana's peakFit scripts on ETMX to check the input diagnolization:

ETMX.png

It's well inverted, but the matrix elements are not great:

       pit       yaw       pos       side      butt
UL    0.3466    0.4685    1.6092    0.3107    1.0428
UR    0.2630   -1.5315    1.7894   -0.0706   -1.1859
LR   -1.7370   -1.5681    0.3908   -0.0964    0.9392
LL   -1.6534    0.4319    0.2106    0.2849   -0.8320
SD    1.0834   -2.6676   -0.9920    1.0000   -0.1101

The magnets are all pretty well centered in the OSEMS, and we worked at rotating the OSEMS such that the bounce mode was minimized.

Rana and Koji are working on ETMY now.  Maybe they'll come up with a better procedure.

 

  5184   Thu Aug 11 08:29:28 2011 steveUpdateComputersdataviewer at Rosalba

I'm having this problem with DTV every morning at Rosalba only. It wants to start with a negative GPS time and it can not connect to the frame builder.

Normally after a few time of starting it, it will work.

Attachment 1: gpsfmb.png
gpsfmb.png
  5193   Thu Aug 11 15:31:43 2011 steveUpdateGeneralmalfunctioning crane at ETMY

Quote:

The horizontal trolley drive stopped working  at the east end this morning. It is working intermittently. In the worst case we can take the door off with the manual -Genie- lift.

I'm working with Konecrane to solve  the wormgear drive problem.

 Gear box found, it's  lead time one week at $825    The crane may be functional round August 25

  5194   Thu Aug 11 16:07:37 2011 steveUpdateSUSETMY rack cables strain releived
Attachment 1: P1080159.JPG
P1080159.JPG
Attachment 2: P1080160.JPG
P1080160.JPG
  5212   Fri Aug 12 16:52:49 2011 steveUpdateGeneralChamber illuminator switch

I'm looking for an ether net based  power switch for turning lights on and off for the vacuum system from MEDM screen.  This is what I found

Jamie please take a look at it.

 

 

  5262   Thu Aug 18 10:59:04 2011 steveUpdateTreasurePrepared for drag wiping

Quote:

While waiting for the IFO team to align things (there were already ~5 people working on a ~1 person job...), I got all of our supplies prepped for drag wiping in the morning. 

The syringes are still on the flow bench down the Xarm.  I put fresh alcohol from unopened spectrometer-grade bottles into our alcohol drag wiping bottles.

The ITMs already had rails for marking their position in place from the last time we drag wiped.  I placed marker-rails for both ETMs.

 We should use the deionizer before drag wiping with isopropanol.

  5264   Thu Aug 18 15:54:35 2011 steveUpdateSUSdamped and undamped OSEMs

damped sus at atm1 and freeswingging sus at atm2

 

Attachment 1: 5susLL.jpg
5susLL.jpg
Attachment 2: 8freeSUSLL.jpg
8freeSUSLL.jpg
  5268   Fri Aug 19 09:14:56 2011 steveUpdateIOOdegrading laser power at atm

Light into the MC is 20 mW at atm, MC_Transmitted ~10 MW = 400 count

The PMC_T is OK but something else is drifting.

Attachment 1: power@atm.jpg
power@atm.jpg
  5269   Fri Aug 19 10:26:53 2011 steveUpdateSUSOSEM sensor spectra

Free swingging OSEM sensors LL at atm

Attachment 1: 8freeSUSosemSensors.jpg
8freeSUSosemSensors.jpg
  5270   Fri Aug 19 15:31:53 2011 steveUpdateGeneralpower interruption rescheduled to 10-1-2011

                UTILITY & SERVICE INTERRUPTION

**PLEASE POST**

 

Building:               Central Engineering Services (C.E.S.)

          LIGO Gravitational Physics building adjacent to C.E.S. 40M- Lab

          Safety Storage adjacent to CES

          Steele House 

          Keck Lab

 

Date:                   Saturday, October 1, 2011

Time:                   8:00 a.m. To 9:00 a.m.            

Interruption:   Electricity

Contact:                Mike Anchondo ext. 4999  Tom Brennan 4984

*This interruption is required for maintenance of high voltage switchgear in Campus Sub Station.

(If there is a problem with this Interruption, please notify

 the Service Center X-4717 or the above Contact as soon as possible.

 If no response is received we will proceed with the interruption.)

         

                                Reza Ohadi,

                                Director, Campus Operations & Maintenance

  5276   Mon Aug 22 11:40:08 2011 steveUpdateVACcranes checked

Cranes are  checked and they are ready for lifting. At the east end will use the manual Genei-lift to put door on.

  5300   Thu Aug 25 08:12:09 2011 steveUpdateSUSETMY & ITMY wiped, replaced, vac door on

Quote:

We've closed up ETMX:

  • the optic was drag wiped
  • the suspension tower was put back in place
  • earthquake stops were backed off the appropriate number of turns, and de-ionized
  • chamber door was put on

 jamie, jenne, kiwamu, suresh, steve

 

ETMY and ITMY were treated the same way as ETMX. The BS chamber was closed with heavy vac door yesterday also. The IOO access connector's inner jamnuts are torqued to 45 ft/lbs as all vac door bolts.

The vac envelope is ready for pumpdown condition, except ITMX chamber with light atm door cover.

Jenne will summeries the condition of dust on the  TMs before and after the drag wipes.

  5303   Thu Aug 25 17:14:49 2011 steveUpdateVACclean room fashion changes

Jamie is modeling our next generation  in-vac & clean room bonny suit that Jenne and myself already tested.

It is quite bearable with our traditional cleanroom beret-bouffant cap. Please use these in the future.

This will help to avoid the farther degradation of somewhat dusty 40m vac envelope.

It is the required dress code to enter the clean assembly room in the 40m.

 We have small, med, large and x-large in stock. I'm getting larger sizes.

It will not allow certain people to climb inside the vacuum chamber in dirty pants.

Attachment 1: P1080185.JPG
P1080185.JPG
Attachment 2: P1080183.JPG
P1080183.JPG
  5306   Fri Aug 26 07:53:59 2011 steveUpdateSUSBroken UL magnet on ITMX

Quote:

Dmass just reminded me that the usual procedure is to bake the optics after the last gluing, before putting them into the chambers.  Does anyone have opinions on this? 

On the one hand, it's probably safer to do a vacuum bake, just to be sure.  On the other hand, even if we could use one of the ovens immediately, it's a 48 hour bake, plus cool down time.  But they're working on aLIGO cables, and might not have an oven for us for a while.  Thoughts?

 Follow full procedure for full strength, minimum risk

  5307   Fri Aug 26 10:45:17 2011 steveUpdateGeneral crane at ETMY is fixed

Quote:

The horizontal trolley drive stopped working  at the east end this morning. It is working intermittently. In the worst case we can take the door off with the manual -Genie- lift.

I'm working with Konecrane to solve  the wormgear drive problem.

 New gear box installed and tested by Fred KoneCranes.

Attachment 1: P1080190.JPG
P1080190.JPG
Attachment 2: P1080188.JPG
P1080188.JPG
  5309   Fri Aug 26 15:59:33 2011 steveUpdateGeneraldrawer cabinet moves in

manufacturer info

Jamie and Shuresh moved in Jenne's 11 drawers cabinet and relocated old note book boxes on the inside of the vac tube.

Attachment 1: P1080192.JPG
P1080192.JPG
  5322   Tue Aug 30 10:49:29 2011 steveUpdateSUSBS & PRM damping restored

I have restored the damping of BS and PRM. Today is janitor day. He is shaking things around the lab.

  5328   Wed Aug 31 11:37:56 2011 steveUpdateGreen Lockingshutter in place at east end

Uniblitz mechanical shutter installed in the green beam path at ETMY-ISCT  The remote control cable has not been connected.

  5331   Thu Sep 1 11:03:22 2011 steveUpdateVACback ground rga scan

The RGA back ground at day 29 of this vent.

Attachment 1: v70-bg-d29scan.jpg
v70-bg-d29scan.jpg
Attachment 2: vent70tempres.jpg
vent70tempres.jpg
  5332   Thu Sep 1 15:07:45 2011 steveUpdateSUSwhy ITMY is moving more ?

Atm1, ITMY and the SRM are on the same isolation stack.  So why does  the SRM move twice as much?

Atm2, We should check the ITMY  SIDE_OSEM before pump down. Anatomically correct, beautiful picture taken by Kiwamu on August 22

Attachment 1: itmy_srm_etmx.jpg
itmy_srm_etmx.jpg
Attachment 2: P8220152.JPG
P8220152.JPG
  5333   Thu Sep 1 15:59:46 2011 steveUpdateSUSlight doors on at the ITMs

Suresh, Kiwamu and Steve

Heavy chamber doors replaced by light ones at  ITMX-west and ITMY-north locations.

  5341   Tue Sep 6 08:05:53 2011 steveUpdateSUSITMX must be touching

Quote:

The new ITMX was aligned by changing the DC biases.

The resultant DC biases are reasonably small.

C1:SUS-ITMX_PIT_COMM = -0.2909

C1:SUS-ITMX_YAW_COMM = -0.0617

 

The alignment was done by trying to resonate the green light in the X arm cavity.

The spot position of the green light on the ITMX mirror looked good. This was confirmed by inserting a sensor card.

I did the OSEM mid-range adjustment and the rotation adjustment but at the end the OSEM DC voltage has changed due to the DC bias operation.

The OSEM rotation was approximately optimized so that all the face shadow sensors are sensitive to the POS motion but the SIDE shadow sensor is insensitive to the POS motion.

It needs a free swinging diagnosis.

 ITMX OSEMs   UL 1.8V,   UR 1.7V,   LR 0V,   LL 0V,   SD 1.3V  at the same bias setting shown above. May be a lose earth quake tip?or magnet is touching?

Attachment 1: osemITMX.jpg
osemITMX.jpg
  5355   Wed Sep 7 08:14:01 2011 steveUpdateSUSfinal OSEM check

All fine, except ITMX_sensor_UL's  60  counts deep hoop for an hour.

Attachment 1: finalcheck.jpg
finalcheck.jpg
Attachment 2: ITMX10min.jpg
ITMX10min.jpg
Attachment 3: finalsum.png
finalsum.png
  5357   Wed Sep 7 12:03:49 2011 steveUpdateVACPump down has started

Jamie and Steve

We closed ITMX and ITMY chambers and started pumping around 11am

What we did before:

1, turned off AC power  to PZT Jena HV ps

2, checked jam nut positions

3, cheched  single o-ring shims

4, closed psl out shutter

  5358   Wed Sep 7 13:28:25 2011 steveSummaryCamerasAll Camera setups a need upgrading

Quote:

I just tried to adjust the ETMY camera and its not very user friendly = NEEDS FIXING.

* Camera view is upside down.

* Camera lens is contacting the lexan viewport cover; this means the focus cannot be adjusted without misaligning the camera.

* There's no strain relief of the camera cables at the can. Needs a rubber cable grommet too.

* There's a BNC "T" in the cable line.

Probably similar issues with some of the other setups; they've had aluminum foil covers for too long. We'll have a camera committee meeting tomorrow to see how to proceed.

 ITMY has been upgraded  here I have the new lenses on hand to do the others when it fit into the schedule.

  5361   Wed Sep 7 18:19:37 2011 steveHowToVACstop pump down for overnight

Quote:

Jamie and Steve

We closed ITMX and ITMY chambers and started pumping around 11am

What we did before:

1, turned off AC power  to PZT Jena HV ps

2, checked jam nut positions

3, cheched  single o-ring shims

4, closed psl out shutter

 We are at 30 Torr of 7 hours of pumping with 2 roughing pumps.

Kiwamu will take over the rest of the roughing today. He will keep an eye on  the pumping speed to be  ~1-2 Torr/min  and open up the manual RV1 valve if needed.

The present status is #3023 of  "chamber open to vacuum open" mode and waiting the P1 pressure to drop to 500 mTorr

He will do the following to stop pumping at P1 = 500 mTorr

1, close V3

2, close RV1 with torque wheel

3, turn off PR1 & 3

4, disconnect metal hose between RV1 and PR3

 I will start the Maglev tomorrow morning.

  5365   Thu Sep 8 10:50:44 2011 steveUpdateVACpumpdown #71 comleted

Vacuum status:  " vacuum normal"   CC1 pressure 5e-5 Torr

Slow roughing through butterfly valve took 11 hours at 1-2 Torr/min speed.  We had a leak at the metal hose connecting o-ring  that became visible  at 200 Torr.

The vacuum envelope pressure rose to 500 mTorr from 450 mTorr  This is 50 mTorr leak plus outgassing over 11 hrs  over night stop =  5  mTorr /  hr

Atm2, Maglev pumpdown details. P2 and P3  are in the foreline of the Maglev. The pressure peaks at 4 Torr beacause the 3 drypumps have  little pumpimg speed at this range.

            External fan is turned on during this one hour period to prevent  Maglev turbo from overheating.

            Same things are  happenning with the two small TP2 and TP3 pumps under load. Their foreline pressure peak at 1 Torr.  They slow down to 45 K RPM from 50K RPM  and warm up to 36-39 C

Precondition: 36 days at atm

Attachment 1: pd#71.jpg
pd#71.jpg
Attachment 2: maglevpd.jpg
maglevpd.jpg
  5366   Thu Sep 8 13:20:07 2011 steveUpdatePEMvac envelope at atm for 36 days

We tried not to open chambers above 10,000 particles of 0.5 micron cf/min

New items going in:                       2 rasor beam traps, 5 badly oxidized old silver plated  setscrew with spring loaded tips......to be replaced in the future, viton tips for eq screws....some are lose, gold plated allen wrench installed at ITMX bottom, reglued magnet on ITMX

Bad hardware things found:          nylon ball "locking elements" on OSEM locking set screws with screwdriver  slot, lose  1064 nm filter on OSEM pd

Attachment 1: vent70.jpg
vent70.jpg
  5395   Tue Sep 13 16:57:44 2011 steveUpdateLSCITMX oplev **

Quote:

I lined up the Y Arm for locking and then centered the oplevs for ETMY and ITMY.

* The ITMY OL has still got the old style laser. Steve, pleaes swap this one for a HeNe. Also the optical layout seems strange: there are two copies of the laser beam going into the chamber (??). Also, the QPD transimpedance needs to be increase by a factor of ~10. We're only getting ~500 counts per quadrant. Its worth it for someone to re-examine the whole ITMY OL beam layout.

* The ETMY OL beam was coming out but clipping on the mount for the ETMY OL HeNe. This indicates a failure on our part to do the ETMY closeout alignment properly. In fact, I get the feeling from looking around that we overlooked aligning the OL and IPPOS/ANG beams this time. If we're unlucky this could cause us to vent again. I undid part of the laser mount and changed the height on the receiving mirror to get the beam back onto the QPD.

I noticed that there is significant green light now getting into some of the IR PDs; beacuse of this there are weird offsets in the TRY QPD and perhaps elsewhere. We had better purchase some filters to tape over the front of the sensitive IR sensors to prevent the couplling from the green laser.

* There is a beam on IPPOS, but its too big for the detector (this has always been the case). We need to put a 2" lens with a weak focusing power on this path so as to halve the beam size on the detector. Right now its clipping and misleading. There is also a 0.9V offset on the SUM signal. I'm not sure if this readout is working at all.

* I couldn't find any beam on IPANG at all. Not sure what's changed since Kiwamu saw it.

 Old Coherent diode laser was replaced by Uniphase HE/NE 1125P at ITMX.

Newport 10B20NC.1 broadband beam sampler set up as beamspitter to dump 90% of the light into beam trap. Beam in to test mass  0.7 mW ,  returning to qpd 0.07 mW  = ~ 3,700 counts

f 1.5 m lens placed into ingoing beam path to reduce the spot size on the qpd.         ITMY oplev will be done in this manner tomorrow.

 

* IP-ANG is lost with the Piezo Jena PS

* IP-POS cable have to be found at the LSC rack

 

  5403   Wed Sep 14 07:51:20 2011 steveUpdateSUSPRM damping restored

The PRM damping was restored at side sensor var 1050

ELOG V3.1.3-