Luke, Deepak, Cheryl, Alex, Rodica

Last week we finished assembling and aligning the IO Faraday isolator on the H1 PSL table. A little more ghost beam hunting is needed, but once all the stray light is contained, the system is ready for high power testing. Without the DKDP crystal yet installed the isolation is 47.8-49 dB, with 96-98% in the returned REFL beam (98-99% transmission assuming equal losses in forward and backward directions) for 500 mW to 9 W incident power. The forward extinction (incident to forward rejected) is >30 dB, and could be improved even further with some more careful finetuning.

The following steps are suggested for high power testing:

- quantify the power in all ghost beams and make sure they are blocked properly

- measure and finetune isolation / transmission up to 150 W without / with DKDP

- measure thermal lensing

The water cooled power meter needs to be moved to measure the powers in REFL and incident beams. Also, it helps if two low power Ophir power meters are used to simultaneusly check isolation and transmission. 

Thanks to everyone at LHO for their great help and support with this!

[Jeff B, Stuart A]

Jeff B posted Phase 1b M1-M1 TFs for PRM (HSTS) in LHO aLOG entry 4195. These recent TFs from 2012−09−06_2000, with damping OFF, show a Y to T coupling at 1.1 and 2.05 Hz. This coupling goes away with damping ON, as can be seen in the TFs from 2012-09-10_0900.

Jeff K had made some comments regarding the nature of this Y to T cross coupling in LHO aLOG entry 3831, outlining possible scenarios for how it could be caused. 

As a consequence, it was requested that Jeff B switched the "side" of the SD BOSEM [i.e. +T] to the opposite side of the PRM structure [-T], and accordingly change the sign of the SD BOSEM gain in the OSEM OUTPUT FILTERS, from -1 to +1.

Following these changes, repeat TFs were taken Friday afternoon for just the T DOF.

A comparison plot showing the TF for the T DOF both before and after swapping the side location of the BOSEM is available below. Pot Key:-

Blue Trace   = Model Prediction
Orange Trace = X1 PRM M1 (2012-09-06_2000) - SD BOSEM on as-built side
Black Trace  = X1 PRM M1 (2012−09−14_1700) - SD BOSEM on opposite side

It can be seen that swapping the side location of the BOSEM appears to have mitigated the Y to T cross coupling!  

n.b. all data, plots and scripts have been committed to the sus SVN as of this entry.

Sno Valley on site
James B. restarted the CDS filesystem
Vincent restarted the H2 DAQ

Attached are plots are dust counts > .5 microns in particles per cubic foot. Also attached are plots of the modes of the dust monitors to show when they were running.

For 20 minutes (from Sep/14/2012 23:56-ish to Sep/15/2012 00:14:15 UTC), one arm was locked with WFS, without excitation/ring-heater, with PSL, before Aidan started injection.

PSL HEPAs, make up air, and ACs were all fully ON.

Anyway, while talking to Aidan I noticed that it was not as glitchy as the day before, and close to the end of the above mentioned period there was a few glitch-free time long enough to capture 8 averages BW=0.094Hz spectrum with dtt, that's whopping 72 seconds of glitch free time per each spectrum!

OK, nothing to be excited about, they (red and blue) look mostly the same as the best-ish data with refcav in the optics lab (green). PSL might be slightly (e.g. 2 dB) better between 1 and 2 Hz.

A cavity scan in running overnight on the single arm with 13.2W of power going into ETMY from the RH.

The RH was turned on around 17:45 PDT. I've turned off the WFS servos and have a dither script running intermittently to take care of the alignment.

The Apollo crew spent the day cleaning the upper chamber, using ONE air drill. They also confirmed the circularity measurements near the turbo pump port taken for AOS. 

IAS,
 Test stand 1 has the modified leg installed. Both test stand are now leveled to the same elevation as measured from the support tube bosses. All 8 corners measured to < 0.1mm using the Sokia autolevel and interpeted as close as the precision scale(rule) could be measured.

ScottL & Hugh
We added the additional counterweight to the WHAM3's East Side per D1000907.  The table now has 15 stacks, 20kg each for 300kg.  Of course the ISI is locked (as is HEPI) and will remain so until remaining Aux/IO (sorry if I have subsystems smeared) items are added to get to final payload.  Then we'll be able to unlock and fine tune the final actual payload.
I had to adjust the position of the two SUS brackets in the mid-right of the photo to make room for the mass on the Northeast corner.  Further, there was an unused bracket North of PR2 that I moved to the South of PR2--unused in that it was connected to the SEI cabling going from the Optical Table down to the feedthru but connected to nothing on the Optical Table.

See the below photo for a view of the East side.

   Filiberto, Andres, and Jeff reconnected the cables to the feedthrough Kyle repaired. MC2 has been reconnected to the test stand and connections were verified. Andres and Jeff made minor centering adjustments to the OSEMs. 

   MC2 is again ready for testing.      

I started up the dust monitor code for the end stations and the OSB optics labs. I also burtrestored the alarm settings. This was needed after h0epics2 got restarted. Someone had already restarted the code for the dust monitors in the LVEA but the alarm settings needed to be burtrestored.

The CDS main file server cdsfs0 glitched this morning at 04:05 and put itself into readonly mode. This is the second time this has happened this week after many months since the last occurance. The other failure this week was at  16:20 Monday 10th.

The two failures are different, Monday locked the computer up completely, today we were able to log in and look at the logs. We cleanly powered it down and Jim performed the power cycle. Everything came back up and the control workstations should be operational.

here are the logs for the two events:

Sep 10 16:20:49 cdsfs0 kernel: [1167428.800898] 3w-9xxx: scsi0: ERROR: (0x06:0x0036): Response queue (large) empty failed during reset sequence.

Sep 14 04:05:36 cdsfs0 kernel: [299840.564536] 3w-9xxx: scsi0: ERROR: (0x06:0x0010): Microcontroller Error: clearing.

We expect remote transfer functions on MC2 over the weekend.

Ridiculous ergonomics pertaining to the center-north flange that was R&Rd significantly limited my ability to do a decent job on the chamber flange (predict 50/50 chance of having to revisit this "leaker").  After several hours of fighting the numerous obstacles, I finally unbolted the dial-indicator "trees" that monitor the support tube motions.  Sorry Seismic.  Unfortunately, this was mostly after the fact.  

We have taken the Phase 1b transfer functions and power spectra for H1-PRM. 
The files from 09/06 are for undamped Transfer functions.
The files from 09/10 are for damped Transfer functions. 
The files from 09/13 are for the damped and undamped power spectra. 

Ken worked at getting an appropriate power supply for the compressor first thing this morning.(Thanks, Richard.) The Apollo crew went into the beamtube to vacuum up all the mess (visible particulate, fibers, metal fines)from the gate valve to the BSC body. Once that task was accomplished,the dust barrier was installed and brushing commenced. About 70% of the collar was brushed by the end of the day.

Scott & Hugh

The first layer of D0901075 mass was positioned (9 pieces on the west, north & south sides) and bolted down sometime ago per D1000907-v1.  I didn't add the second layer so as to improve the access for cable routing and other work.  The six stacks (12 pieces-120kg) have not been added to the east side of the ISI table.
Today we put the second layer, another 90kg, on to the first layer of positioned stacks. These are secured with final fasteners.
See the attached photo for a view from the west.

With the go ahead, I'd like to get the rest of the payload in position asap but only if it won't interfere with Aux/IO work.