Matt, Rolf, Dave, Alex (remote)

We got the Biquad filter module working in the new CDS system and made a few simple tests.  For these test I created a few somewhat complex filters:

• Pass 1Hz - a resonant filter which passes 1Hz and the cuts off steeply
• Not 1Hz - a 1Hz notch filter with 120dB of attenuation, also has a pair nearly canceling poles and zeros at 10mHz
• HP 1k - a high-pass filter, flat above about 1kHz

The first test was to check the transfer function.  The biquad filter matched the the standard filter (direct form 2) with various combinations of the above filters.  No problems were observed.

The noise test was designed to match the test performed at the 40m lab in March 2008. With all of the above filters engaged, a 1 Hz sine wave with amplitude 1 was injected into the input of the biquad filter and a standard filter module. In the frequency region where the noise is amplified by the HP filter, the biquad filter produced a numerical noise floor 8 orders of magnitude lower than that of the standard filter. Furthermore, the harmonic distortion seen in the standard filter was absent in the biquad.

- Laser Safe today.
- RichardM, CyrusR and FilibertoC out to work by SUS stand by HAM12
- TerryS and crew mopping in the LVEA by BSC7 and BSC10
- MichaelR installing acoustic enclosures by H2 PSL, drilling into studs.
- RichardM works on TCSX access controls
- DaniA works on TCSY dark study
- Ski and Control Solutions technician out to MY to work on HVAC control system
- Paradise Water arrives in the morning
- Apollo crew working at EY
- DI water overflowed in LSB Fiber Lab at ~15:50. Clean-up is ongoing, LisaB supervising.
- Clean room craned to HAM12
- Sock placed on top of BSC7's dome
- GregM gave seminar on Fourier Transformations
- DaniA gave laser safety orientation to SURFs
- Particle counts high in OSB Bake Oven Lab (see Kyle's entry), HAM12 (mopping), H2 PSL (mopping).

Over the past several weeks I have been notified by Patrick and Jonathan of intermittent high particle counts being recorded in the bake oven room (room 169).  These high counts don't necessarily correspond to times when people are present in the room -> 

Initial investigation shows that the dedicated exhaust fan (added to exhaust any "smells" that could eminate from the hot ovens to the building exterior and which is separate from the HVAC) has 0.6" H2O accross its iris damper while nominal has traditionally been 0.5" H2O.  The variable speed adjust is set to minimum speed which is normal and should result in 0.5" H2O drop when all other air supplies/returns are nominal.  Ski confirms nothing has changed recently in the HVAC system supplying this and adjacent rooms. Also, the fume hood switch is in the on position as is nominal.  

I noticed that the ceiling tile located directly above the particle counter shows evidence of having been removed recently (caulking seam separated with visible gaps around tile periphery).  I will see to it that this tile gets caulked and attempt to verify the the fume hood fan is actually working.  Also, its time for a general clean-up in this room.

Opened Vertex to the YBM and X-end for a couple of hours for the squeezer folks.  Vertex and X-end pressures too high to leave opened to BT for any extended period.

Need to review user settings for Corner Station large ion pumps -> seems like maximum power setting is set too low and/or current limiting "I-protect" option not as expected.  

Apollo clening in new transmon lab at end Y
Cleaning at BSC7 in preparation for in chamber cleaning
Assembly of clean room for mechanical test stand
Drilling for floor bolts for squeezer table stand
Gate valves opened for locking H1 X arm
CDS work on electronics racks in LVEA for H2 ITM cartridge install
Cardboard recycling pickup

The dust monitor at location 4 was pulled outside of the clean room at ~22:00 UTC.

Summary of work performed 6-11th June. Rolf, Dave, Richard, Cyrus. Computing and Networking

We have installed five front end computers in the LVEA on the outside of the Y arm, next the the TCS systems. Four of these computers have IO Chassis attached and are

The fith machine is h2tcsl0 which is waiting on its Chassis.

All four machines are running IOP models and user models. All were built against RTS branch-2.3.

Networking was installed in the LVEA to support these systems. A Workstation was installed (on the CDS LAN) next to the racks. More workstations will be moved into the inside of the arm when needed.

Note:  The measured dewpoint of the blow down air, i.e. the air comming out of the +1 psig VE, was -6C while the air sourced from the purge air header measured the normal <-54C.  Prior to valving-in the pumps to a vented volume I typically close the vent valve to the VE and measure the air sourced from the purge air header then close-off the header air and open and measure the air blowing out of the slightly pressurized VE.  Normally the two measure the same as you would expect and are "off scale" dry.  In this case, the two were much different.  I repeated this measurement a few times and the values were exactly repeatable.  I conferred with John W. and decided to begin pumping the "wet" VE anyway.  

The ambient humidity is high today.  I intend to investigate with the people involved with today's unlocking if they had closed-off the purge air during the in-chamber activity for some reason or if they had blocked off 1/2 of the door opening as is the norm.  Not doing so would negate the effectiveness of the purge air's ability at keeping wet room air from mixing with the chamber interior air and might explain this observation. 

I opened GV7 too.  

The mid stations don't have their pressure gauges cabled and CDS indicated values are bogus.  Y-mid seems slow to change and is still indicating ~8 x 10-8 torr at the turbo inlet.  

H1 ETMX was unlocked
HEPI welding continues
HAM 7 HEPI install work
assembly of test stand cleanroom
CDS work on electronics racks in LVEA for H2 ITM cartridge install

Since the test stand upgrade, the side OSEM sensor channels (X1:SUS-QUAD_M0_OSEMINF_SD_IN1 and X1:SUS-QUAD_R0_OSEMINF_SD_IN1) have been very noisy, to the point where enabling the SD DOF control loops would trip the watchdog because of HF signals amplified by the upward slope in the software output filter.

The noise looked vaguely digital in dataviewer but it was hard to tell due to the poor time resolution, and until today we hadn't probed in more detail. However doing a triggered time response measurement in DTT revealed that an otherwise plausible looking signal is being chopped by a rectangular window at 16 Hz with a 1/8 duty cycle (i.e., 1/128 s on out of 1/16 s). See the attached plot, which shows X1:SUS-QUAD_R0_OSEMINF_SD_IN1 (which exhibits the problem) against X1:SUS-QUAD_R0_OSEMINF_F1_IN1 (which doesn't).

The North end of HAM 7 has had the weldments and crossbeam attached. It was a very tight fit to move the crossbeam between the two chambers. Some creativity was called for, but installing the crossbeam for HAM 8 may require even more. The next steps will be to finish the clamp on the crossbeam and torque the bolts all of the bolts.

The HEPI Plumbing is now in the LVEA.

Image1 is the turns up on the Mezzinine.  #2 is below the mezzinine heading into the LVEA.  #3 is in the LVEA at the piping bridge.

The two stages of the first BSC-ISI have been released and balanced. 

Stage 2 total mass is 235 lb under the 6240 lb nominal. So we'll use 550 lb of mass on the keel mass instead of 785 lb. I am going to communicate the number to SYS so they can adjust their models and balancing.

Stage 1 is 135 lb under nominal (out of 8250 lb total on the large blades), about -45lbs/corner, which is very good.

Thanks to all the team for all the efforts to make it possible to float the platform only 5 weeks after we started the assembly.

We now start the testing of Unit #1, and keep working on the assembly of Unit #2. 

EX (BSC9) was prepared for door removal and unlocking of the ETM tomorrow morning.
Work at EY to prepare for receipt of BSC6.
Vacuum prep room of OSB is getting some ridiculously high dust counts. Kyle speculates that it could be air flow issues, and notes potential changes to the exhaust fan in that room.
Construction of a tall clean room in the LVEA got as far as an unadorned structure today, waiting for a ceiling, electrical appliances, curtains, etc.

Burped GV15 gate annulus into aux. cart, cracked GV15 to pump X2 hydrogen while X-end isolated.

Power Spectrum of LHO SUS Test Stand without any OSEMs. Disconnect at the point where octopus cables would attach. 

Interesting harmonic of interest at 16 Hz in side channel.

AC power harmonic in all channels (60 Hz)

Sam and I, with much help from Richard, Filiberto, and Carl, have populated the two racks for the Single Arm Installation.  For the corner, the chassis are in, and the internal wiring is all hooked up.  At the end, most of the chassis are in, but Rolf is using the IO Chassis, and two binary chassis for some testing in the computer room, so those parts are not yet installed.  All of the cables are, at least, attached at one end, waiting for the IO chassis, or Binary chassis.  We just finished making the field cables that we need to test, and we will start testing this morning.
-Ben