With lots of work by many over the last few weeks, we are at a point where the TMS Lab is Operational.  We still have a few more parts to bring down there, but for the most part, we are getting there.  Assembly work (i.e. parts being un-bagged could happen next week) is coming soon and we'll want to transition access to this lab to requiring Full "Bunny" Suit garb (will put a sign up saying so when we are assembling). 

We also moved a Dust Monitor from EY to EX (it wasn't on the network and I notified Patrick about this).

There is a visible air gap in the Entry Door to the lab.  I've been told we covered this up for EY, so we'll want to probably mimic that soon (because Chris has noticed quite a few bugs in this room during her daily cleaning.

These tables (currently in East Bay/Squeezer Area) were cleaned by Christina/Karen, and are now ready to be occupied (although they are pretty low priority schedule-wise).

ChrisM, MichaelR, GregorioT, RickS

This morning, we moved the periscope structure about a foot toward the BSC chamber, lifted it off of the teflon highway strips using the jack screws and support plates, installed the flexures, loaded them using the flexure adjustment screws, and removed the support plates so that the structure was supported by the flexures only.

Everything went smoothly.   The structure appears to be very rigidly mounted when on the flexures.  We were not able to move it, even with some pretty hard bumps.

We then lowered it back on to the teflon highway strips using the jack screws and support plates, slid it down the staging location at the BSC end of the A7 Adapter, supported it in the adapter using the upper and lower support plates, removed the stabilizing slides, rotated it 90 deg. to its staging orientation, and installed the rotation stabilizing bars.  (See photos).

We did all the work today from the BSC side only.  We wanted to try this because we won't have access to the other side when the Cryopump/Manifold baffle is in place.  It was easy working from the BSC side, so no reason to go to the other side.

The A7 Adapter flange protectors arrived just after we finished our inside work.  We installed them on the flange (see last photo).

We plan to leave the Pcal periscope structure in this location and orientation until the Cryopump/Manifold baffle is installed, then move it into the final location next to the baffle and do the final alignment with the help of IAS.

In order to reduce the motion of the quads at low frequency, I added resonnant gain filters called "LOCK" to the medm filterbank of etmy and itmy. Those filters are designed to help locking the cavity, damping the 0.43Hz and 0.99Hz resonnances of the first longitudinal modes and 0.56Hz of the first pitch mode. The stability of the closed loop hasn't been studied yet, but it looks to be working fine for now. The second and third pictures attached are showing the shape of the damping filters with and without the "LOCK" filter engaged. Those filters are engaged with a ramping time of 10sec.

Since the IMC feedback to the laser is disturbing the fiber PLL lock in the end station, we have temporarily hooked up a fixed frequency oscillator source to drive the AOM in the fiber distribution chassis. The RF doubler has been left in the electronics chain as well. The source is currently set at 79.4 MHz / 13 dBm. This frequency should match the PSL VCO frequency as close as possible.

During testing, we saw that actuator V4 of HPI BS was not able to deliver full power. We didn't try to fix the problem (risk of disturbing alignment). The HEPI at the beam splitter is now controlled in position at 100mHz. We will come back to the problematic actuator later.
Some correction gains were applied to the HEPI actuators to compensate for differences in the actuator drives. The correction gains are:
 

The offsets used on the IPSs are:

60 days of pumping on END Y.

Exponent of T appears to be close to 1 now which means the outgassing may be dominated by water from the surfaces. Have we depleted the reservoir of gas in our cables?

I added a plot and comments to my report yesterday on the LVEA HEPI Pressure loss.

report

(Jax)

This was completed yesterday but I got caught up in measuring everything else on ISCT1 so this just didn't make it to the alog until today.

The power out of the SHG on ISCT1 looks best at 34C. 

Data to support this:

Note: I'm aware that these values look a little low, this isn't an isolated problem. It's in the queue to get addressed, but isn't at the top of the priority list because there's enough power here to get a usable beat note.

(Chris, Kiwamu, Stefan)

We started off by relieving all MC offsets to alignment sliders, and setting some electronics offsets on the MC board. Next we aligned the whole HIFO-Y (green pointing into the arm, PR3 for green transmission, PR3 & IM4 for maximum IR fringing, PRM for maximum power recycling fringing).

Next we peaked into HAM1 and identified the REFL beam - it hits the vacuum chamber right next to the view port. So tomorrow we will have to do another incursion to HAM1 to get that beam out.

Next we touched up the beat node on ISCT1. With 0.1mWatt into the beam combiner from the SHG, and 1.4mWatt from the y-arm, we expected a maximum of 220Vpkk (assuming 1kOhm transimpedance and 0.6A/W). we got 150mVpkk.

Next we checked out the electronics. The cable from the common PD went to the differential PFD (Phase Frequency Discriminator), and vice versa. So we switched the cables. Next we noticed that the Bekoff control between COMM and DIFF is also switched - this needs to be fixed.

Next we started playing with the feedback to the IMC and PSL. We were able to get the PFD off the rails by some slow feed-back to MC2, but unfortunately we have no way of doing this without already putting a signal into MC2 length. Next we tried to simply increase the the REFL_SERVO_SLOW to MC2 length gain, but we get an oscillation at 6Hz to 8Hz (depending on the slow integrated). It seems like we are missing some filters in the chain...

Looking at DTT spectra of H1:IMC-L_OUT and H1:LSC-CARM (both frequency sensors) we find that the PFD is still in the non-linear regime. The 8Hz signal upconverst noise everywhere, dominating the frequency noise in H1:IMC-L_OUL (the two signals look identical, with opposite sign).

So we have a chicken and egg problem: no signal from ALS_COMM without feed-back, and no feed-back without checking that the signal makes sense.

In other words: It is time for a complete IMC and ALS model in MATLAB - otherwise we are running blind.

These are the latest TF/Spectras Test Results for HSTS I1-SRM

For a while the 227b dust monitor in this clean room has been reporting high counts. (see attached plot back to May 15th)

One theory was that this may be due to a missing prefilter on one of the HEPA units. (alog 6375)

This cleanroom is split in two, with a garbing area on the HAM2 side and cleaned parts on the other. Each half has two HEPA units. The HEPA unit with the missing prefilter is over the cleaned parts. The 227b dust monitor is also in this half.

This morning I took further measurements with one of the HHPC-6 particle counters. In the cleanrooms over the two test stands, and the larger one closer to HAM3, the counts were flat zero.
The counts I measured in the small cleanroom with the HHPC-6 appeared to confirm earlier counts with the 227b. The counts were elevated in both halves. I did not see a noticeable difference directly under the HEPA unit with the missing prefilter. However, inside the cleanroom near the floor of the entrance to the gowning side, the counts were repeatably and exceptionally high, I believe up to from 480 counts at 0.3 um to 160 counts at 5.0 um.

I plan to do more detailed measurements tomorrow.

I was up on the Mezzinine measuring for cables and noticed that the pumps were not turning.  No level trip, no VFD trip, servo running pushing max volts.  Richard reminded me of a problem that we should have corrected some time ago.  The output from the servo has 4 BNCs to the four pump stations.  There was a bad BNC that has shorted in the past and it did so again.  Once it shorts, no matter what the servo does, the outputs are shorted and the VFD gets zero volts hence no revs.  As soon as I unplugged the bad BNC they rev'd back up.  We took it back down and Filiberto replaced the BNC.  This should not happen again.  I may have bumped the cable and caused the short but I'm pretty sure it happened 10s of minutes before I was in the area.

The pumps went down at ~1818utc and the BSC2 HEPI moved a fair bit, several .001".  After the BNC repair I got the Pump Output back to operating pressure ~2040utc with the HEPI Actuators reaching equilibrium position a few minutes later.  The difference in before & after position at BSC2 was ~0 to ~600 counts, all less than 0.001".  Obviously a need for alarms--working on it!