Schedule for BSC9 Vent and ETMX Assessment and Cleaning
Approved work to be done:

1.   Assessment and cleaning of ETMX HR surface
2.   Replacement of EX viewport plexiglass window inserts

Tuesday, Dec. 16

• 1st cleaning of BSC9
• Move Clean Room (CR) into position for BSC9
• Check rooftop of Clean Room and attach sock, verify fans are working
• Start collecting supplies: FC, solvents (acetone), Green Lantern, Flashlights, PET contamination kit, ...

Wednesday, Dec. 17

• Turn on purge air for BSC9
• Move supplies: FC, solvents (acetone), Green Lantern, Flashlights, PET contamination kit, ion gun, etc. from BSC10 area to BSC9  and make sure CR supplies are in place (gowns, change room, ...)
• Dust Monitors - verify operation
• Make safe.snap files to save settings
• Follow M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown", Turn off high voltage
• Review and follow E1201035, "aLIGO Chamber Entry & Exit Procedures" checklist
• Review and follow M1100068-v1, "Hanford Checklist - BSC Door Removal", Review door removal procedure with crew
• Start vent on BSC9

Thursday, Dec 18

• 2nd cleaning/wipedown of BSC9
• Install plexiglass viewport window inserts
• Continue following E1201035 check list
• Lock down HEPI
• Remove door
• Document entrance
• Enter and secure ISI and SUS
• Assess quality of HR surface of ETMX with green flashlight - if "clean" then close up, otherwise perform a First Contact cleaning, cover, and allow to cure.

Friday, Dec 19, 2014

• Peel First Contact and assess quality of ETMX
• Prepare to close WBSC10 EY as per  E1201035, "aLIGO Chamber Entry & Exit Procedures" checklist
• Review and follow M1100068-v1, "Hanford Checklist - BSC Door Removal"
• Unlock ISI and Optic
• Verify optic is free
• Assuming all goes well, obtain approval and signatures for volume closure (M1300172).
• Notify door crew to hang door
• Verify readiness to pump down, follow M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown". Confirm all high voltages are off.
• Notify Vacuum crew of readiness to start pumps

The last step is at the time and discretion of the Vacuum crew.

Kyle, Gerardo, Bubba -> Installed HAM1 east door (every other bolt) -> Pumping annulus 

Kyle, Gerardo -> Closed GV20 -> Started slow vent of X-end 

Bubba -> Staged/Status prep for BSC9 West door removal slated for tomorrow morning 

Kyle, Gerardo, Bubba -> Installed BSC10 North door -> Not pumping BSC10 annulus or Y-end until others "sign-off" on readiness tomorrow 

LVEA: Laser Hazard
Observation Bit: Commissioning  

06:15 Karen & Cris – Cleaning at End-Y
09:16 Elli & Thomas – In the LVEA working on HWS alignment
09:25 Hugh – Working on HAM3 CPSs
09:35 Aaron – In Beer Garden terminating cables
10:00 Jeff &  Nutsinee – Tour of LVEA
10:15 Water sampling company on site to test water
10:26 Betsy & Travis – Going to End-Y
10:30 Kyle, Bubba, & Gerardo – HAM1 door install
11:08 Cris – Taking garb to End-X
11:40 Thomas & Elli – Out of the LVEA
12:08 HAM1 door installed
12:30 Dave & Jim – Going to End-Y to connect a HWD monitor cable
13:00 Manny – Dropping of parts at End-X
13:05 Shut down Picomotors at End-X to prep for vent
13:10 Kyle – Going to End-X to soft close GV20 for vent
13:30 Bubba – Going into the LVEA to gather tools for End-X Vent
13:32 Manny – Delivering parts to End-Y
14:00 Rick – Going to End-Y
14:30 Started venting BSC9
15:30 Robert – Going to beam enclosure just short of Mid-Y

Krishna, Sheila, Hugh, Fabrice:

We have been chasing  large amplifications at low frequencies (in the range of 10mHz to 30mHz) caused by the Z zensor correction of HEPI, which is necessary to reduce the Z to RZ coupling on Stage 1. It looks like the Z HEPI inertial isolation is causing rotations (RX, RY), that are causing tilt signal in the Stage 1 horizontal seismometers, that couple to X and Y as we blend at 45 mHZ, and then shows up into the cavity signal.

The problem was mostly  visible on the BS unit.  We convinced ourself that Z to tilt  was the problem by moving Stage 1 in high blend, which very significantly reduced the Mich amplification around 20 mHz (which exist only when the Z sensor correction is ON)

It seems that the excessive Z to tilt coupling in the BS was caused by off centered  vertical position sensors (up to 24000counts). We recentered them by applying  a HEPI vertical force. The Z to Mich coupling is now much lower. So I guess that the gain of the sensors was affected by the large offsets and thus creating excessive Z to RX and RY couplings.

Comparison with high blend configurations show that there is probably room to further reduce this coupling. We need the measure the Z to RX and RY coupling and apply corrections.

Dave, Jim

To perform some further HWWD testing at ETMY, we have temporarily connected the HWWD RMS analog monitor (BNC output on rear of unit) to a spare PEM channel on its AA chassis. We are reading the channel using the slow IOP DAQ channel. The plot shows 1 minute of full 16Hz data during the recent ETMY in-chamber work. The 1.6 second integration time can be easily seen in the data.

We are using the next to last channel on the PEM AA chassis, this is ADC3, Ch30 (counting from zero).

Recent in-chamber work on ETMY has provided a OSEM PD RMS trip level comparison between the Hardware watchdog (HWWD) and the IOP software watchdog (SWWD).

We have verified that the two systems have very similar trip levels. The SWWD trip level is hardcoded at 110mV. The HWWD level can be modified, but it is running at its default of 110mV.

The plot shows: the PD RMS status for the SWWD (Ch 4, GOOD=1, BAD=0); and the HWWD (Ch 2, GOOD=0, BAD=1). Also shown is the SWWD RMS monitor for the ETMY top stage OSEM, SIDE channel, which is the channel driving the RMS errors.

As can be seen, Ch4 and Ch 2 match each other very well.

Note that the maximum time in error in this plot is only 3 minutes. If the excitation were to extend to 10 minutes the SWWD would have tripped the SEI DACs, and if it were to extend to 20 minutes the HWWD would power down the ISI coil drivers.

Approved work to be done:

1.   Cleaning and assessment of ETMY HR surface
2.   Replacement of EY ESD vacuum feethrough connector assembly
3.   P-Cal alignment

Thursday, Dec. 11

• 1st cleaning of BSC10
• Move Clean Room (CR) into position for BSC10
• Vacuum rooftop of Clean Room
• Attach sock
• Start collecting supplies: FC, solvents (acetone), Green Lantern, Flashlights, PET contamination kit, ...

Friday, Dec 12

• 2nd cleaning BSC10
• Turn on purge air for BSC10
• Make sure CR supplies are in place (gowns, change room, ...)

Monday, Dec 15

• Dust Monitors - verify operation
• make safe.snap files to save settings
• Follow M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown", Turn off high voltage
• Review and follow E1201035, "aLIGO Chamber Entry & Exit Procedures" checklist
• Review and follow M1100068-v1, "Hanford Checklist - BSC Door Removal", Review door removal procedure with crew
• AM
  • Start vent on BSC10, estimate ~5 hours [Kyle and John]
• PM - follow E1201035
  • Lock down HEPI
  • Wipe down cleaning to ensure area is clean
  • Remove door
  • Document (photograph) entrance and assess for obstructions (hanging cables, loose wires, ...)
  • Enter and secure ISI and SUS
  • Follow E1400472-v3, "Test Mass In Situ Cleaning Procedure", continue on to Tuesday, Dec. 16. Note that First Contact cleaning is preferred and drag wiping is only to be used as a last resort (see procedure and flow chart in E1400472-v3). The only approved solvent for this cleaning work is acetone.

• ESD Connector Repair

After Chamber Vent Following E1400430
1: Disconnect external (air side) ESD cable from feed thru.
2: Install flat surface with Vacuum Foil on it near Flange for a work
surface.
3: Remove ESD feed thru flange  Gerardo
4: IF enough cable exist cut the cables from the connector on the inside.
    IF not enough cable disconnect cable
    disassemble connector then remove connector ends.
5: Crimp new pin on to cables.
6: Verify with SUS which pin is connected to which part of ESD.
7: Make up connector with new pins in proper order D1400177 V2
8: Secure new connector to new feed thru.
9: Install Flange on Vacuum chamber.  Gerardo
10: Connect new external cabling to feed thru
11: Ensure no one is near optic!!!  High Pot connector ~ 700V DC  If it
doesn't pass.  Stop and investigate.
12: Make up external cables to field current limiting resistor box.

Tuesday, Dec. 16

• AM
  • Continue with ETMY cleaning as described in E1400472-v3. Note that First Contact cleaning is preferred and drag wiping is only to be used as a last resort (see procedure E070304 for drag wiping). The only approved solvent for this cleaning work is acetone.
  • Meet with SYS and COC team members to assess.
• PM
  • Perform spot cleaning on edge in attempt to understand First Contact edge contamination ring.
  • Apply 2nd round of First Contact, cover, and allow to dry and cure over night.

Wednesday, Dec. 17

• AM
  • Peel First Contact and assess the situation with SYS and COC
• PM
  • Prepare to close WBSC10 EY as per  E1201035, "aLIGO Chamber Entry & Exit Procedures" checklist
  • Review and follow M1100068-v1, "Hanford Checklist - BSC Door Removal"
  • Unlock ISI and Optic
  • Verify optic is free
  • Assuming all goes well, obtain approval and signatures for volume closure (M1300172).
  • Notify door crew to hang door
  • Verify readiness to pump down, follow M1300464-v4, "Procedure for preparing aLIGO IFO for pumpdown". Confirm all high voltages are off.
  • Notify Vacuum crew of readiness to start pumps

The last step is at the time and discretion of the Vacuum crew.

Took dust monitor trends from End-X ahead of the vent. Posted are a 7 day trend for both location #1 and #2 and a 72 hour trend. The first cleaning and cleanroom over BSC9 were turned on 12/16/14. 

Here is an estimate of the BRDF for ETMx and ETMy from the recent scattering images we took. 

BRDF=Ps/solidAngle/Pinc/cos(theta_s), in W/steradian , as quoted by Hunter Rew in P1400197.  Ps is power incident on photodiode, solidAngle is that subtended by the photodiode, Pinc=incident power (here the IR power inside the arm), and theta_s is the scattering angle, which is the angle of the photodiode from normal incidence.  SolidAngle-A/L where A is the area of the photo diode and L is its distance from the test mass.

Ps=calibration_factor*Intensity/Exposure, where calibration factor is in (W*microseconds/counts) and is defined by David Feldbaum in LLO alog 12627, intensity is the total pixel counts on the CCD, and exposure is the camera exposure in microseconds.

Pinc is calculated using Dan's calibration of the TMS photodiodes outlined in alog 15431.

A is as given by the camera specs = 1.0209e-05 m^2.

Rick Savage and Joe Gleason helped me get the distance and scattering angle of the camera from the mirror.  L is 6.0452m and theta_s is 4 deg for the ETMS. .

The other paramters used are:

Because these images are taken at small angles, its not valid to assume the BRDF is constant, so its not meaningful to integrate the BRDF to get an estimate on total scatter in ppm. I wanted to compare numbers to the ITMs, however I can't because the analogue gain setting was different (1023 not 100) for the ITM pictures.  Once ETMy is clean and we have the Y-arm back I will re-measure ETMy and also add numbers for the ITMs.

ITM03 - had a full sheet of FC applied with NO IAS windows, see attached.  ITM03 was installed in BSC3.

Thomas V, Elli

The ITMy and ITMx Hartmann wavefront sensors are now aligned to their respective SLEDS.

We took the HWS plates out and centered the SLED beam on the camera using the periscope mirrors and the final mirror before the HWS (pictures of the final alignment on the camera are included).

The ITMx image is a lot dimmer than the ITMy image, however the H1:TCS-ITMX_HWS_SLEDPOWERMON  said 5mW whereas H1:TCS-ITMY_HWS_SLEDPOWERMON says 1.8 mW.  We were watching to maximise image brightness as we made the adjustments so I don't know why ITMx image is so much dimmer.

This morning, travis and I pulled the FC sheet that we applied to the ETMy yesterday.  The patchy smudge mark and the large gooeyish particle that we induced yesterday were apparently picked up by this FC sheet.  While there, we tested using the cotton tipped Q-tip on a portion of the ring around the edge of the optic (~1Inch in from bevel edge near the bottom).  We used both DI water and also acetone, both chased with ~5 spot drag wiped of acetone using the pressure technique.  Upon evaluating neither q-tip+ acetone drags seemed to improve the area since both swipes added to the streaking which the chasing acetone could not fully remove with 5 wipes.