This entry is just for a record.
I took a look at the ALS fiber path on the PSL table since I happened to be there for some other works today. The drawing below shows a power budget of the current fiber setup.

Started reworking on EY ALS table.

Green beam was injected into the chamber and PZT servo was enabled to center the beam on QPDs. Whitening gain of QPDs were very high again so we had to decrease the servo gain by a factor of 100. Whitening gain MEDM screen was all white so we left it as is.

After confirming that the beam was centered on all four irises, we started removing the Faraday from Drever lab and realigning.

Some observations:

• EOM transmission is crappier when the beam goes through the center of the input and the output hole. It looks best when the beam is almost clipping high at the input hole and centered at the output hole.
• The steering mirror upstream of the EOM was shooting the beam down significantly.
• When we put the correct Faraday in position (in the tilted beam path downstream of EOM), there're like 12 ghost beams in transmission.

We'll level the beam path and start over tomorrow though we don't know if doing so will improve the transmission quality.

I was hoping this (and power cycling the end link chassis) would get rid of errors on the bridge terminal, but there are still errors on the bridge terminal even in the init state.  

GregG & Hugh

We put the eight HEPI actuators of HAM2 in bleed mode and opened the 4-way valves and then ramped the fluid pressure back up to max.  We did this 4 times to be cautious about fluid leaks--we did this at each pier and carefully checked for leaks before ramping the pressure back down and opening the valves at the next pier.  The introduction of additional resistance has us at 28psi now with the motors running about 92% and the servo on.  We will continue these steps at WHAM3 and possibly HAM1 and/or BSC1 over the next few days.  Additional chambers will allow us to get higher pressure and so more nominal performance.
While the HEPI is locked, we did see some readout change on the IPS.  The signs are all the same and the largest is about 300 counts or ~0.0005".  I suspect this is mechanical distortion of the Actuator itself with the pressure introduction.  Since the IPS is all attached to the actuator both the Flag (unsuspended) and Sensors (suspended), I don't think this can be checked independently.  I would venture that the Platform has not actually moved.  After a couple days of bleeding, we'll switch the Actuators to run mode.  This will likely change the pressure/IPS state again so hold on!  We'll likely want to have enough Actuators on line so that we can servo the pressure at nominal level(80psi, 70diff) so the introduction of additional actuators will not change the actuator distortion/IPS 'zero'.

I created the new safe.snap files for the EY systems. I made the name change to the alarm handler files (both CDS and WATCHDOG). I found I had not actually changed h1iopiscey from PEM to ISC, so I changed that and restarted all models on this front end. Several DAQ restarts were performed for these and user model changes today. The PSL ENV slow controls channels were added back to the frame.

These are the TF/Spectras Test Results for HSTS I1-PR2

The polarization of the IMC REFL beam on IOT2L was measured.
It was found to be about 80 degrees off from S-polarization while pure S-polarization is desired for the optics in the RFPD paths.
This explains the recent funny splitting ratio of the 50/50 BSs in the RFPD branches [1][2].


Background :
 We found that the 50/50 BSs were not splitting the beam with a correct splitting ratio. To understand the current situation we decided to measure the actual polarization.

 
No polarization correcter :
 Apparently there is no polarization correcter in the current setup. This is another reason why the splitting ratio was funny. We used to have a HWP to rotate the polarization to S (see for example [4]). However I found that this had been put aside out of the main path for some reason. I guess this is because the setup is still under the process of rebuilding. Anyway according to the latest diagram [3] there will a calcite polarizer in addition to the HWP which then spatially separates the S and P polarizations. A quick fix would be to simply place the HWP again in the path if necessary.


Measurement:
 I inserted a corner cube PBS (PBSC-1064-50) to measure the polarization in-situ on the IOT2L table. The measurement was done in two places : one right after the bottom periscope mirror and the other after the window (IO_MCR_AR1). I put a convex lens in front of the PBS to make the beam go through the PBS. Note that the measurement was done before I increased the incidnet power on the IMC.

  Measurement 1 : Right after the bottom periscope mirror
  transmitted light (P-pol) = 141.0 mW
  reflected light (S-pol) = 26.6 mW
  polarization angle from S-pol = atan(141 mW / 26.6 mW) = 79.3 deg

  Measurement 2 : After the window (PBS was placed after IO_MCR_M6)
  transmitted light (P-pol) = 4.72 mW
  reflected light (S-pol) = 0.75 mW
  polarization angle from S-pol = atan(4.72 mW / 7.5 mW) = 81.0 deg

So the beam is pretty far off from the desired polarization of S currently. The PBS and lens were removed from the table.


[1] LHO alog 6264 "DC calibration of IMC WFS"
[2] LHO alog 6297 "IMC incident increased to 1 W"
[3] DCC D0902284-v9
[4] DCC D0902284-v7
 

- Vacuum alarm: criopump 5 were refilled, Kyle mention that tomorrow and next Tuesday, Wednesday and Thursday will refilled other criopumps, so, expect this alarm

- PSL alarm: there is a problem with H1:PSL-OSC_LPSCLSD and H1:PSL-OSC_PWRDOGON channels, neither M Rodruck, nor Dale understand what is going on. Will need further study

- FMCS alarm: max temperature of MID X and Y will be set at 85F. The sensor for H0:FMC-CS_LVEA_ZONE4_B_DEGF seems that is broken, Ski will unplug it.

- Dave restarted all DAQ at 11:42

- SUS watchdog alarm: ETMY and SEIB6 were all invalid. Dave, Cyrus, Richard diagnosing network switch problem at EY. All EY DAQ data bad since 9am. Cyrus found a broken fiber. Solved ~13:30.

- LVEA Crane survey continues

- M Rodruck and Filiberto installing cables into H2 LEA for Pcal pre-alignment

- Keita working on the TMSY ~14:00

- Robert S. from ~12:40 to 2:30 working outside, tube's enclosure, between OSB - MX

- Kiwamu increased the laser power into the IMC to 1W

- Thomas working on viewports, laser into HAM1 has being shuttered, contact him before unshutter it
 

-Moved the Genie snorkel lift from High Bay to LVEA so that the LVEA camera could be cleaned for Richard and then moved the Genie back to High Bay so it could be inspected by Mid-Columbia. 
-X End work continued. Test stand cleanroom was rolled out of the VEA to the middle bay so that picking eyes could be fitted and attached. The picking eyes, taken from the "dirty room", required a slight modification before they could be attached. Holes were drilled in the cleanroom frame and the eyes were attached this afternoon. The table that sits on top of the TMS Bosch frame was moved into the lab to clear space in receiving. Work to clear interferences for IAS table placement is on-going.
-Provided support for OpLev work: Mick worked with Thomas and Tyler fabbed a cover for an OpLev camera.
-Provided support to SEI.

The laser power incident on the IMC was increased to 1 W per WP3869.
It will stay at this power level during HIFO.

Preparation
In preparation to increase the power I did the following things:

•  Removed a beam dump which had been in the main PSL path right after the EOM on the PSL table.

This dump was something people put to block the beam during the high power adjustment in the last two days.

• Measured the power of the main PSL

After the EOM = 1.203 W

In front of the bottom periscope mirror = 167.7 mW
(This was then increased to 1.00 W)

• Measured laser power on the IOT2L to make sure that increasing the power doesn't damage the diodes.

Note that I intentionally misaligned MC2 during the measurement on IOT2L by disabling the pitch offset of 407 urad in M1.

This was because I wanted to avoid fringing in the reflected light.

Adjustments.

  The incident power onto the IMC was adjusted to be 1 W by rotating the half-wave-plate in the last attenuation stage in front of the PSL periscope. Note that this rotational stage doesn't give us more than 1.2 W since the power is already limited by another attenuator in the upstream. Then I checked the power on the diodes on IOT2L to make sure they are working OK with the new power level. The power were measured to be :

Length RFPF = 9.3 mW
WFS A = 6 mW
WFS B = 13.6 mW

All of them show reasonably big DC signals in the digital system and seems fine although I didn't check the RF signals yet.

Moved the interface box to the Turbo pump to eliminate interferences with new equipment.  Also move a conduit that would interfere with the oplev pier. 

New fibers were run to the network switch in the vacuum rack and connected to the fibers for the corner station.  Cyrus will get the network running and connect the HEPI servo

We are tracking a network switch/fiber patch problem which has caused the DAQ data from EY to be bad from 9am onwards.

I have enabled jumbo frames in the core switch on all interfaces expected to require them in the future - this is largely to prepare for implementing the gigabit ethernet video cameras.

While I expected this to be a non-destructive change, apparently it interrupted the inter switch trunk links long enough to crash the Comtrol based systems (dust monitors and weather stations) and potentially caused the EDCU to drop channels.  Those systems have been (or are) being restarted.

In addition, I have enabled jumbo frames and loaded new IOS code on sw-msr-ops, sw-msr-server1, sw-lvea-aux0, and sw-msr-gc, but these switches have NOT been restarted for jumbo frames and the new IOS to take effect.  This will be done during the next available maintenance period.  The code version installed is 15.0.2-SE2, upgraded from 15.0.2-SE1.  15.0.2-SE2 has already been installed and tested on the (new) sw-msr-server2, and appears to be an uneventful upgrade.

(Michael R., Rick S., Oliver P.)

After turning on the high power satge, the amount of light in the FSS path was about six times higher than in the low power mode. To operate the FSS properly, the amount of light at the RF photodiode had to be attenuated. Therefore, we add an additional R=80% splitter to the beam phath. Also, the lens, focussing the beam to this diode had been exchanged: the focal length is now 100 mm instead of 50 mm, which gives more space for the beamsplitter, the diode itself, a stirring mirror in front of the diode and a beam dump, blocking the light, reflected from the chip (see the attached picture).
We were able to lock the FSS. The measured parameters are as follows:

power downstream of the Faraday isolator behind the reference cavity:  39.0 mW

DC voltage at photodiode in reflection, if locked: 0.052 V

DC voltage at photodiode in transmission, if locked: 1.119 V after optimizing lambda/4 wave plate

We adjusted the unity gain frequency using RF analyzer. The common gain has been set to 16 dB. We found the unity gain frequency at 309 kHz with 44 deg of phase margin.

If the FSS remains unlocked, the powers and voltages are:

RFPD DC 0.386 V

incident on RefCav 73 mW --> 86.5% visibility (including sidebands)

total power transmitted by RefCav: 43.5 mW

h1dc0 disappeared from medm screens running on the OPSLAN. Initially I thought it was a cds-h1fe epics gateway error and I restarted that, but it did not fix the connection. I ran a DAQ MEDM on the FELAN and verified h1dc0 was running correctly, at which point the OPSLAN MEDM came to life but showed the EDCU disconnected from 1130 channels. I logged into h1dc0 and it verified it was not connecting to 1130 channels but did not give a disconnected channel list. When this had happened before we suspected the Beckhoff OPC-IOC and its epics gateway, so I restarted the h1slow-h1fe gateway, which did not fix this. Vincent needed a DAQ restart, after the restart the EDCU was happy again. Looking at channel lists in EDCU  ini files I cannot find a single system with 1130 channels in it.

Transfer functions are running overnight on HAM2-ISI.

[Chris W. Mark B. Arnaud P.]

Thanks to the generous help of Chris, the problem of binary I/O control has been finally solved. The routing of the monitoring signals was wired incorrectly in the model. More details in the attached screenshots.
First picture shows what part in the model has been modified, the two others show the actual change.

The model has been commited on the svn. LLO model is consistent with LHO.

Szymon and Mark B.

We extensively revised the TMTS model using first article data from Ken Mailand. The preferred model is now at

^/trunk/Common/MatlabTools/DoubleModel_Production/tmtsfa.m

In conjunction with the DTT data plotting script

^/trunk/TMTS/Common/MatlabTools/plotTMTS_dtttfs.m

it gives a respectable fit to measured data:

^/trunk/TMTS/H1/TMSY/SAGM1/Results/2013-03-14_1936_H1SUSTMSY_M1.mat
^/trunk/TMTS/H1/TMSY/SAGM1/Results/2013-03-14_1936_H1SUSTMSY_M1_ALL_TFs.pdf

The biggest mismatch is that an R (Mathematica/Matlab pitch) mode predicted for 0.6 Hz is observed at more like 0.7 Hz. Everything else is pretty much bang on.