Bulb  is replaced.

Light bulb replaced.

Bulb replaced at day 110  We have now spare now.

I replaced the projector bulb. Previous bulb was shattered.

The control room's north west corner smelled like propane gas  yesterday around 16:30

We all agreed that the smell was real and I called the safety office. I was told that they received 6 other calls from different parts of the campus.

The smell disappeared in about a half an hour.

Property tag found.

The major changes from the previous layout:

1. I've depicted the Green reflected beam path more accurately - I approximately measured the angle of the rejected beam from the faraday from the Y-end setup. This looks like a workable solution, and is similar to what we have currently at the Y-end
2. I've added some optics to monitor the DC power and RIN of the AUX laser
3. I've added two lenses to the input path of the Oplev beam (the path is such that I think we can use the same lenses that are currently being used. 
4. I've now drawn the beams in CAD so that is marginally neater.

To do:

1. Post mode matching solutions for AUX laser to doubler and green beam to arm for this proposed layout (should be identical to what we have now, which at least according to the calculation is a good solution, but I will double check - I also need to quantify what the effect of the elliptical beam is)
2. Check the Gouy phase of the transmitted IR beam at the QPD - we may need to change some lenses in this path. But I think the path as such is close enough (distance-wise) to what we have currently at the X end (after accounting for the fact that the new endtable edge will be closer to the ETM) so I don't expect this to be a show-stopper.

Does any part of this layout need a radical redesign? 

I realized I had overlooked an important constraint in the layout, which is that the enclosure will have two supports that occupy some region of the table - these are denoted in blue in v3 of the layout (Attachment #1). I measured the dimensions for these from the existing Y-endtable. The main subsystem this has affected is the IR transmission monitors, but I've been able to move the photodiodes a little to accommodate this constraint.

I've also done the mode-matching calculations explicitly for the proposed new layout (Attachments #2 and #3, code in Attachment #4). While the layout was largely adopted from what Andres posted in this elog, I found that some of the parameters he used in his a la mode code were probably incorrect (e.g. distance between the 750mm lens and the ETM). More critically, I think the Gouy phase for the optimized solution in the same elog is more like 60 degrees. I found that I could get a (calculated) Gouy phase difference between the two PZT mirrors of ~81 degrees by changing the green path slightly, and making the two PZT mirrors Y7 and Y8 (instead of Y7 and Y11, for which the Gouy phase difference is more like 50 degrees). But this way the two steering mirrors are much closer to each other than they were before. Other misc. remarks about the mode matching calculations:

• The beam diameter at the locations where the Faraday isolators should go is well below 5mm, the aperture size of the Faraday isolators
• The calculated mode-matching efficiencies suggest that we don't need any cylindrical lenses though the mode from the NPRO is elliptical
• Attachment #5 is a CAD drawing of the layout with all dimensions used for the mode-matching calculations included (although they are in inches)

These changes also necessitated minor changes to the transmitted IR beampath and the Oplev system, but these changes are minor. I've also switched the positions of the AUX IR power monitoring PD and the fiber coupler as suggested by Koji. The shutter has also been included. 

Rana advised that we put in a lockin-output matrix which will allow us to excite any combination of MC mirrors so that we can excite pure translations or rotations of the MC beam axis.  This would require us to direct a lockin output into all the three mirrors simultaneously with a +1 or -1 as needed in the matrix..

Granite base 20" x 20" x 5"  locations are on the CES side of our IFO arms:  as shown ETMY_ south-west, ETMX_north-east, ITMX_south-east . No height limitation. This side of the tube has no traffic.

SS cover McMaster#  41815T4  (H) SS container cov

This is my interpretation of where Steve is proposing to place the seismometers (he wrote ITMX southwest, but I'm pretty sure from the photo he means southeast).

I think his point is that these locations are on the less-used side of the beam tube, so they will not be in the way.  Also, they are not underneath the tube, so we will not have any problems putting the covers on/taking them off.

I am going to tweak the alignment of the beam into the AOM (before the PMC) tomorrow morning. If anybody has any objections to this, please raise a red flag.

Proposed alignment procedure:

1. Reduce PSL power to say 10% 

2.  Since the AOM is not on any sort of a mechanical stage, I will have to just play around carefully until I see a maximum power rejection into first order.

I am assuming that moving the AOM is not going to affect the input pointing because all these activities are happening before the PMC. So as long as I have the output beam from the AOM aligned to the PMC at the end, everyone should be happy.

I made the following change to correct the sign of the 126MON channel:

allegra:c1aux>ezcawrite C1:PSL-126MOPA_126MON.EGUF -410
C1:PSL-126MOPA_126MON.EGUF = -410
allegra:c1aux>ezcawrite C1:PSL-126MOPA_126MON.EGUL 410
C1:PSL-126MOPA_126MON.EGUL = 410
allegra:c1aux>

As we learned yesterday, the PSL laser power out put mechanical shutter is not working in the remote mode. It only works in local manual mode.

Do not rely on the MEDM screen monitor readout! The position is only changing on the monitor. The main beam must be blocked before the output periscope.

Some thoughts on what happened with the MOPA cooling. 

Some unknown thing happened to precipitate the initial needle valve jiggle, which unleashed a torrent of flow through the NPRO.  This flow was made possible by the fact that the cooling lines are labeled confusingly, and so flow was going backwards through the needle valve, which was thus powerless to restrict it.  The NPRO got extremely cold, and most of the chiller's cooling power was being used to unnecessarily cool the NPRO.  So, the PA was not getting cooled enough.  At this, point, reversing the flow probably would have solved everything.  Instead, we turned off the chiller and thus discovered the flaky start-motor capacitor. 

Now we have much more information, flow meters in the NPRO and main cooling lines, a brand-new, functioning needle valve, a better understanding of the chiller/MOPA settings necessary for operation, and the knowledge of what happens when you install a needle valve backwards.

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

 PSL shutter is opened.

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

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

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

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

 I can not understand what really happened here with CC1 gauge or there was really a pressure glitch.

attachment 1,  pump down day 3 with 4th of July fireworks in the lab

attachment 2,  before and after vent in 9 days

I stopped puming at 9:30 PM and the pressure in P1 is at 450 mtorr.

I followed exactly he procedure that Steve noted on his elog entry.

Here is a plot of the histroy of our pumping today.

 IFO P1= 1mTorr,   CC1 = 5e-4 Torr.  The IFO is ready for work. Be free to open the shutter and turn on HV

Jenne will double check the MC -REFL path for 1W power.  There is a manual block on the PSL table.

Atm1,  Pirani gauge at 9 h 10 min

Atm2, Pump configuration of pd#73 at 9h 35 min

 The new cold cathode gauge CC1 is in place. We were at atmosphere for 28 days ......more later

 cc1 = 2.3e-5 Torr at day 6 vacuum normal

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

 We are pumping down. The annuloses are below 10 mTorr

The vacuum gauges are not communicating with the medm so there is no plot available.

The main volume pumping is stopped at P1 = 220 Torr  ( New SuperBee 174 Torr ) for overnight.

note: SuperBee was reading 791 Torr at atm and it was not set to 760 !

P1 IFO pressure is 1 mTorr, valve configuration: vacuum normal, annulosses are pumped, RGA is off, not pumped.

THANKS to Chris !

The shutters can be opened with high power.

No communication error message still exist.

I will reboot c1vac1 and c1vac2 to get gauge communication with medm tomorrow.

The pumpdown started at 9-12-2016

The IFO is at 5e-5 Torr vacuum normal after 73 day at atm.

ITMX needed to be freed and ETMY-UL is still misbehaving occasionally.

New pirani   and cold cathode gauges added at this vent. They were baked at 100 C for 6 hrs under vacuum.

Go to the Vac Rack to read IFO pressure from the gauge itself when Vac. Monitor is blank as it is now !

IFO pressure 3.7e-5 Torr at new cold cathode InstruTech - Hornet

New items in vacuum:

1, ETMX sus tower with new baked sus wire, EP30-2 epoxied magnets, same at different locations also........ ..........  and 2 ruby wirestandoffs.

2, First Contact cleaned arm test masses only. This technic was a 1st time use in our vacuum system.

3, 50 mm ID green glass baffles at the ends

4, witness mirrors at ETMX and ITMY (old oplev mirrors) We observed a very dusty system: sides of optics, towers and tables were wiped. Hepa tents used at Y arm and BS

5, new pirani, cc gauge and 1.5" right angle valve

The manual gate valve scan was clean. Atm1     TP1 was pumping on it overnight.

                                                Pumpdown continued to hand over the pumping to TP1 maglev turbo

V1 was opened at P1 400 mTorr  with manual gate at 3/4 turn open position as Magev at 560 Hz rotation.

Two aux fans on to hold tubo temps TP1 & TP3 . Atm3

This is the first time we pumping down from atm with ONE small "beer can" turbo  and throttled gate valve to control load on small turbo forepump

The 70 l/s turbo is operating at 50k RPM, 0.7 A and 31 C,  pumping speed  ~ 44 mTorr/h at 200-400 mTorr range with aux drypump in the foreline of TP3

Watching foreline pressures and current one can keep opening gate valve little by little the so the load is optimized. It is working but not fast.

Let's keep small turbo at 0.8 Amp and 32 C max at this pumpdown. 

IFO P1 6e-4 Torr,  manual gate valve is fully open

The annuloses will be pumped down tomorrow.

Valve configuration: vacuum normal, RGA and annuloses are not pumped

Precondition:  4 days at atm.   Atm5

HEPA tent used during the vent at ETMY  It reduced partical count 10 fold of 0.5 and 0.3 micron particals. Atm6

New items in vacuum:  Clean manual gate valve [Cetec made] from John Worden with 6" id....as it came from Hanford... [ Throttle able gate valve- TGV ] Atm3

                                 ( note: we have 3 more identical in the lab. The original intention was to use them for purging gates )

                                  Optiform Au plated reflector , Induceramics heating elements, similar as existing Cooner cables and related lenses, hardwear. see 14078

                                  OMC related item : none......... 14,110

The pumpdown is at 510 mTorr with RP1 & RP3 still pumping. Koji will shut it down the roughing later tonight. Tomorrow morning I will start the pumping by switching over to TP1 maglev.

Thanks for Koji and Gautam'  help of the installation of the manual gate valve. Atm4  This will allow us to control the load on our Varian foreline D70 turbo TP3

10:20PM

• Opened VM2 to pump down the RGA section with TP1
• Stopped rotary roughing pumps
  • Manually closed RV1
  • Closed V3
  • Stopped RP1 and RP3
  • Vented the RP hose

The P1 pressure is 380mTorr. I allowed Gautam to use the full PSL power (~1W).

[koji, gautam]

As planned, we valved off the main volume and the annuli from the turbo-pumps at ~730 PM PST. At this time, the main volume pressure was 30 uTorr. It started rising at a rate of ~200 uTorr/hr, which translates to ~5 mtorr/day, which is in the ballpark of what Steve said is "normal". However, the calibration of the Hornet gauge seems to be piecewise-linear (see Attachment #1), so we will have to observe overnight to get a better handle on this number.

We decided to vent the IY and EY chamber annular volumes, and check if this made anu dramatic changes in the main volume pressure increase rate, presumably signalling a leak from the outside. However, we saw no such increase - so right now, the working hypothesis is still that the main volume pressure increase is being driven by outgassing of something from the vacuum.

Let's leave things in this state overnight - V1 and V5 closed so that neither the main volume nor the annuli are being pumped, and get some baseline numbers for what the outgassing rate is.

IFO pumped down from 44 mTorr to 9.6e-6 Torr with Maglev  backed with only TP3

Aux drypump  was helping our std drypump during this 1 hour period. TP3 reached 32 C and slowed down 47K rpm

The peak foreline pressure at P2  was ~3 Torr

Hornet cold cathode gauge setting:   research mode, air,

                                                            2830 HV  1e-4A  at 9.6e-6 Torr,

                                                         [  3110 HV  8e-5A at 7.4e-6 Torr one day later ]

Annuloses are at 2 Torr, not pumped

Valve configuration:  vacuum normal, RGA is still off

PSL shutter is opened automatically. Manual block removed.

End IR lasers and doublers are turned on.

NOTE: Maglev " rotation X " on vacuum medm screen is not working! " C1:Vac-TP1_rot " channel was removed.  Use " NORMAL X " for rotation monitoring.

*We removed this (i.e. rotation) field from the MEDM screen to avoid confusion.

 It took 15 days to reach 1e-5 Torr

The RGA was turned on yesterday. The rga scan plotting was not working. Den wrote a Python script to log and plot because the Mathlab had trouble receiving data from our old c0raga.

It turned out that the Joe's log&plot system was working today. Thanks Den and Joe.

Here is the first rga scan.

 We are pumping down with RP1 & RP3 oily roughing pumps at 3 Torr/min speed. The butterfly valve was just removed.

The PSL shutter is open to vacuum at ~100  mW 1064 nm. The inter lock should close it at ~5 mTorr.

Rana will shut down pumping tonight.

He will close V3 from screen, close RV1 valve with torque wheel, turn off roughing pumps and disconnect hose between RV1 and roughing pumps.

I will restart pumping early morning tomorrow.

[Rana, Yuta, Koji]

21:05 at the pressure of 10torr
V3 closed. RV1 manually closed. RPs were turned off. And the bellows between RV1 and the rughing pumps are disconnected.

 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

 All normal, IFO pressure 1.5e-5 Torr

RGA is pumped by TP-3 in back ground mode.