FW0 RAID Reconfigured

Completed reconfiguring the external RAID array attached to FW0 under WP 4158, to match the configuration on FW1.  (Note that I had the two FW designations reversed in the original work permit text - it was in fact FW0 that was reconfigured, FW1 was untouched.)  It took approximately 3.5 hours to backup the minute trends to the SATABoy, with the SSD filesystem at 40% utilization.  For a nearly full SSD filesystem, expect the backup to take the better part of a day.

HEPI - DC Bias Function

A very simple function was made yesterday to help with the HEPI alignment work. It takes an 1x8 vector as input, and puts its content into the DC biases of a given HEPI. It may, or may not, be useful later on.

It is saved under the svn as:
/ligo/svncommon/SeiSVN/seismic/HEPI/Common/Testing_Functions_HEPI/Set_HEPI_Cart_Offsets.m     -r7597

BSC-ISI & HEPI - Macro Substitutions Installed

Macro substitution text files were intalled for all H1 HEPI and BSC-ISI. 

The IOP_NAME macro substitution was added. It corrects the issue seen with the display of the IOP Watchdog status, on the BSC screen. Befrore/After comparison is attahced.

The SITEMAP.adl was updated, and chamber names (bscX) were added to the labels. A screenshot of the new sitemap is attached.

The macro substitution text files, and the new SITEMAP.adl were commited to the SVN. Details below:

IMC sideband sweep first measurements

[Kiwamu, Stefan, Joe, Paul]

The first measurements for the IMC g-factor have been made, using the sideband sweep method described in e.g. LLO alog 4849 (https://alog.ligo-la.caltech.edu/aLOG/index.php?callRep=4849).

The broadband REFL AIR photodiode was used to observe light transmitted through the IMC while the 45MHz EOM input was driven from the HP network analyzer in the LVEA. We used the minicircuits RF amplifier which is currently clamped to the ISC rack to get enough drive voltage on the EOM: roughly 10Vpp at 30MHz. An iris was used to partially block the beam on ISCT1, breaking the symmetry on the PD such that the higher-order mode signals were not cancelled out due to their spatial orthogonality.

The attached plot shows the transfer function from network analyser drive signal to BB REFL AIR measured signal, over a range of about 1 FSR. The central peak can be attributed to the HG00 mode, but also displays the resonance of the EOM driver circuit at ~45.5MHz. The HG10/01 and HG20/02 mode peaks are clearly visible, and match up nicely with a Finesse model setup of the measurement. 

To measure the resonance frequencies of the higher-order modes more accurately, and hence to get an accurate value for the IMC g-factor, we will take zoomed in sweeps around these higher-order mode peaks soon.

Faraday isolation ratio measurement

(Kiwamu, Paul, Stefan)
This morning we found the back-reflection from the PRM, leaking through the Faraday, back on the PSL table.
We measured the following powers:
- direct beam, sampled by ~30% BS: 339mWatt
- return beam, sampled by the same ~30% BS: 37.0uWatt
- as reference, we also measured the power on the REFL beam on ISCT1, just after the periscope: 6.94mWatt

Faraday isolation ratio: 37.0uW/339mW, minus other losses (IMC visibility, PRM reflectivity)

H1 PSL weekly trends

Doug was tied up with alignment work at Xend today so I did the weekly trends - see attached images.

Note that the PSL shut down yesterday due to another power glitch.

cables swapped on rotation stage in CSR

Patrick T., Thomas V.

Last night Thomas and I swapped the temporary cables being used to test the rotation stage in the CSR with the ones made for the final installation. These are not pulled yet, but are coiled in front of the rack holding the Beckhoff PSL environmental chassis and attached to a rotation stage sitting on a rolling table nearby.

For some reason two cables had been unplugged from the controller box (goes between rotation stage and Beckhoff module). One was power and the other was a control cable. I'm not sure why they were unplugged, but we reattached them.

I was hoping this would address problems we were having getting the rotation stage to move, but they have persisted.

Patrick T., Thomas V., Vern S.

It would appear after testing that the rotation stage itself is burned out.

MSR cooling cycling

1st of month, I cycled the idle cooling unit in the MSR. Middle unit is now resting.

updated psl safe.snaps

I updated the safe.snaps for h1pslfss, h1psliss, h1pslpmc with the current configuration.  I am also setting the current on the kepco HV unit to 400mA.  

Actually, that was me, signed into the log as jeff.  

Faraday isolator isolation ratio measurement setup

[Kiwamu, Sheila, Stefan, Paul]

Today we tried to get the Faraday isolation ratio measurement using the method Chris Mueller described in his LLO alog 8608, but were unsuccessful so far. 

First we had to restore the IMC and several other optics to their previous state after the power outage. We tried looking for the return beam with the viewer cards, but we didn't find any beams that were not present when the mode cleaner was unlocked (as the true PRM reflection beam would be). We expect this is mainly due to misalignment of the return beam from PRM with respect to the IMC, such that little of the return beam actually makes it back through the IMC, instead being reflected from MC3. At LLO when making this measurement this alignment state was already know well since the central IFO alignment can be used as a reference there.

We tried scanning the PRM alignment, but to no avail. We checked at what PRM alignment offsets the REFL beam on ISCT1 becomes clipped, because this gives a good indication of the alignment parameter space for PRM which we need to search within: if the FI rejected beam is not making it back through the Faraday correctly, then the beam we're looking for is certainly is not making it back through the IMC. The beam became clipped within ~±500 urad of our inital alignment values in pitch and yaw. As a rough comparison, IMC transmitted power can be expected to halve for a MC2 pitch misalignment of 60urad, so it looks like we still have some alignment parameter space to search before we would even expect to see the return beam

The other issue we were dealing with was the back reflection from the second mode matching lens, which was close to parallel (~1 deg) with the forward propagating beam. We aligned a PDA55 to this beam as reflected from the second pick off beam-splitter in the path, since it serves as a reasonable reference for the sought after PRM return beam. In order to help us locate the PRM return beam, as well as for the reason that it had to be done at some time anyway, we decided to rotate this lens (see Cheryl's post from yesterday). We were able to do this, apparently without causing too much change in the alignment into the IMC since the IMC transmitted power recovered to its previous value (~1240 counts on MC2 trans) with the WFS loops engaged. The back reflected beam from the second mode matching lens is now easily separated from the forward beam, and has been dumped on a razor blade dump. We estimated the power in this beam to be around 1mW in the absence of the pick off beamsplitters and with the power through the EOM at 1W.

Today's Saga with the H1 Isolation Systems

J. Kissel, H. Paris, A. Pele, S. Ballmer, C. Wipf

Yet again today we battled with the HEPI and ISI systems in the ITMY (BSC1) chamber trying to get them back after the weekend's power outage. HEPI is up and running again, but I don't think at the same alignment. The ISI cannot make the final transitions to awesome without its watchdog tripping. Details below. 

I'm leaving the entire ITMY (BSC1) and BS (BSC2) chambers OFF for the evening so DetCharians can follow up on a study of the 10 [Hz] HEPI pier amplification *AHEM* Laura Nuttall *AHEM*. 
Ground STS2 Channels          ITMY HEPI L4C Channels              BS HEPI L4C Channels
H1:ISI-GND_STS_HAM2_X_DQ      H1:HPI-ITMY_BLND_L4C_X_IN1_DQ       H1:HPI-ITMY_BLND_L4C_X_IN1_DQ
H1:ISI-GND_STS_HAM2_Y_DQ      H1:HPI-ITMY_BLND_L4C_Y_IN1_DQ       H1:HPI-ITMY_BLND_L4C_Y_IN1_DQ
H1:ISI-GND_STS_HAM2_Z_DQ      H1:HPI-ITMY_BLND_L4C_Z_IN1_DQ       H1:HPI-ITMY_BLND_L4C_Z_IN1_DQ
H1:ISI-GND_STS_HAM5_X_DQ      H1:HPI-ITMY_BLND_L4C_RX_IN1_DQ      H1:HPI-ITMY_BLND_L4C_RX_IN1_DQ
H1:ISI-GND_STS_HAM5_Y_DQ      H1:HPI-ITMY_BLND_L4C_RY_IN1_DQ      H1:HPI-ITMY_BLND_L4C_RY_IN1_DQ
H1:ISI-GND_STS_HAM5_Z_DQ      H1:HPI-ITMY_BLND_L4C_RZ_IN1_DQ      H1:HPI-ITMY_BLND_L4C_RZ_IN1_DQ
H1:ISI-GND_STS_ITMY_X_DQ      H1:HPI-ITMY_BLND_L4C_HP_IN1_DQ      H1:HPI-ITMY_BLND_L4C_HP_IN1_DQ
H1:ISI-GND_STS_ITMY_Y_DQ      H1:HPI-ITMY_BLND_L4C_VP_IN1_DQ      H1:HPI-ITMY_BLND_L4C_VP_IN1_DQ
H1:ISI-GND_STS_ITMY_Z_DQ 
which I've confirmed are in the frames. Chris is going to do a few more things with the IFO, but things should be off by 00:00 PDT, 07:00 UTC Oct 1 2013, 1064646016.

--------
HPI-ITMY

The goal here was to get HPI to the same alignment we had during HIFO-Y (see LHO aLOG 6566). However, the biases had been reported in the Colocated basis and we want to progress forward, sticking these biases in the Cartesian basis in calibrated units. After a few unsuccessful attempts, we finally

- Turned the position isolation loops OFF
- Turned the input to the IPSINF banks OFF
- Inserted the desired input readings as offsets in the IPSINF bank
- Read off the corresponding values at the input to the blend filter bank (letting the front end do the appropriate basis conversion and calibration for us [thanks Stefan!])
- Turned the IPSINF offsets OFF
- Turned the input to the IPSINF banks ON
- Turned the 100 [mHz] UGF "position" lock isolation loops ON (watching as the inputs meander off to some weird location)
- Installed the desired Cartesian values and a 10 sec ramp into the DCBIAS bank, turned them ON.


For the first few minutes, the plan worked like a charm; inputs to the IPSINF moved to exactly where we wanted them. However, after those few minutes and currently, the location has drifted to some other location, mostly in horizontal DOFs. Other commissioners were not as successful at restoring light this far into the interferometer, so we never got the chance to test whether this alignment is good enough. Out of frustration, we'll leave it as is.

Here're the final results:
Colocated Channel             Value [ct]  |  Cartesian Channel               Value [nm or nrad]    CART Bias Channel              [nm or nrad]    
H1:HPI-ITMY_IPSINF_H1_INMON    -873.2     |  H1:HPI-ITMY_BLND_IPS_X_INMON    -7156.64              H1:HPI-ITMY_DCBIAS_X_OFFSET  = 7156
H1:HPI-ITMY_IPSINF_H2_INMON    -822.083   |  H1:HPI-ITMY_BLND_IPS_Y_INMON    -33425.1              H1:HPI-ITMY_DCBIAS_Y_OFFSET  = 33425
H1:HPI-ITMY_IPSINF_H3_INMON   -2786.58    |  H1:HPI-ITMY_BLND_IPS_RZ_INMON   -4374.85              H1:HPI-ITMY_DCBIAS_RZ_OFFSET = 4374
H1:HPI-ITMY_IPSINF_H4_INMON   -3773.34    |  H1:HPI-ITMY_BLND_IPS_HP_INMON   -1073200              H1:HPI-ITMY_DCBIAS_HP_OFFSET = 1073200
H1:HPI-ITMY_IPSINF_V1_INMON   -6121.07    |  H1:HPI-ITMY_BLND_IPS_Z_INMON    -71553.4              H1:HPI-ITMY_DCBIAS_Z_OFFSET  = 71553
H1:HPI-ITMY_IPSINF_V2_INMON   -1038.65    |  H1:HPI-ITMY_BLND_IPS_RX_INMON   -46597.7              H1:HPI-ITMY_DCBIAS_RX_OFFSET = 46597
H1:HPI-ITMY_IPSINF_V3_INMON    2772.24    |  H1:HPI-ITMY_BLND_IPS_RY_INMON   +72672.               H1:HPI-ITMY_DCBIAS_RY_OFFSET = -72672
H1:HPI-ITMY_IPSINF_V4_INMON   -2990.78    |  H1:HPI-ITMY_BLND_IPS_VP_INMON   +75188.8              H1:HPI-ITMY_DCBIAS_VP_OFFSET = -75188 

      
-------
ISI-ITMY

The goal was to get the ISI in as best-performing state in order to use the GS13s (our best sensors of the isolation system at this point) to measure whether the 6.18 [Hz] feature had been reduced as much as had been shown by Arnaud in LHO aLOG 7919. As Hugo had stated earlier (see LHO aLOG 7915), he and Arnaud got things most of the way up, but not nearly as good as Vincent's work during the original discovery (see 7747) because the configuration Vincent outlines has just enough typos to be confusing.

So, I tried my hand at it, having had a few more conversations with Vincent about the configuration but to no avail. My attempts failed at various points along the way, but most often because the watchdog would trip on the actuators as I'd tried to switch in the T240s to the ST1 blend filters. I'm too tired to dig in deeper, but we'll try again tomorrow.

Here's what I found broken / frustrating / interesting along the way:
- The ISI-ITMY model must not have been restored to a good time (or not at all). The damping loops were OFF entirely (inputs, outputs, gains, and filters). I restored them by hitting the "damp ITMY" command script.
- The damping loop status lights are red when functioning nominally. The "correct state" is set to 0x6000034, when the current state is 0x1401 and the loops are running as designed. This should be an easy fix.
- ctrlDown of the isolation loops is now a part of the front end, so one no longer needs to remember hit the command button before restarting the isolation process.
- The ST0 to ST1 feed forward is not a part of the ctrlDown or isolate command scripts. One has to manually remember to SLOWLY ramp them off (or on).
- The Sensor correction is not part of the ctrlDown or isolate command scripts. One has to manually remember to SLOWLY ramp them off (or on).
- The Sensor Correction overview screen is grouped by degree of freedom instead of by instrument source -- and otherwise it looks identical. These should be at least *colored* differently. It's tough to tell whether I'm turning on the ST0 L4C sensor correction (which I shouldn't) or the GND STS2 sensor correction (which I should).
- The TRAMP for the MATCH banks on the Sensor Correction overview screen is missing. I had to dive into the MATCH banks internal screen to get to the TRAMP.
- The full filter bank sub-screens for anything on the Sensor Correction overview screen are not obviously accessible. You can do it by just clicking around blindly and landing on a hidden link, but there's no obvious button like there are for most other sub-screens.
- The FULL command script for "isolate ITMY lvl3" froze several times in the middle of ramping up ST2. I didn't diagnose why, but it fails in the middle of ramping up the ST2 RX and RY loops. I had to run ctrlDown and run each of the Stages (and at one point each of the degrees of freedom) separately.
- The "isolate ITMY lvl3" script turns on the "Boost_2" filters.

Here're some good philosophical discussions that came up:
[Kissel with himself]
- "There's a 'switch all' screen on the blend filter screen for each stage. Vincent at one point [a month ago now] had set it up that -- even though not all of the blends were the same for each DOF -- the Y DOF's filter characteristics defined the name of all the DOF's filter names for that level of button. This way, the user knew 'I get the best performance if I hit the "T40mHz_NO.44' button on the switch all' screen." This is opposed to having to know the best blend for each of the 6 DOFs and in which order to switch them in. 
I prefer the "one-button switches in all the right blends." Much better for configuration control.

[Ballmer with Kissel]
- Instead of writing in Perl, Python, or folding it into the Guardian structure, we should now have the ability (thanks to the cdsCtrlFilt2) to move the entire isolation loop turn on dance into the front end as a c-code state machine. This, if coded correctly
(1) shouldn't take more than a month off offsite development, 
(2) removes all reliance on the EPICs network and interaction with scripts,
(3) makes the user/guardian interface a more straightforward state-machine, and
(4) removes flexibility to mess things up.
I think we should do it.

Transfer Function Running on ITMX on the test-stand overnight

HugoP, JimW

After finishing up floating and balancing the ISI this morning (Stage 2 was floated on Friday, Stage 1 required minimal adjusting this morning), we started testing the ISI in the afternoon. First we built and installed a recently updated BSC model, then populated the MEDM, then used a somewhat shady epics variable short cut (exclusive to the ISI test stand) to de-activate the SUS watchdog (the quad is on stops, so the watchdog is not doing anything right now, anyway). After all that, we were able to start driving, first the actuator static local basis test to verify the actuators behaving properly, and now an overnight transfer function. Should finish by the morning meeting.

EX Beckhoff started

With Patrick and Filiberto's help, the EX Beckhoff system is now running.  The Twincat System Manager sees all EX components, and keepalive signals are propagating down the fiber link from the corner to EX and vice versa.  Here's the documentation we followed to get the fiber links working: http://infosys.beckhoff.com/english.php?content=../content/1040/el6692/html/bt_el6692_functionality.htm

MEDM screens went live after we started Maggie's EPICS server, using the command C:\SlowControls\EPICS\Utilities\Bin\start_h1x1.bat

Cabling out to the electronics in the VEA still has to be set up and tested.

6.18Hz sat amp

[Hugo Jeff Arnaud]

Now that one of the satellite box of ITMY (see 7780) has been changed, and following Jeff's and Vincent's investigation on the 6.18Hz noise injected from sus to sei (see 7720 7709 and 7609 for details), a spectra of GS13 on stage 2 of ISI has been taken (using Vincent's scripts), as well as a spectra of the left and right osems before and after changing the sat amp, with the ISI isolated level 3, and the suspension with all the damping loops closed. The pdf attached are described below :

(1) Light blue is GS13 from Sept 10th before the sat amp was changed, and the 6.18Hz peak is present. Dark blue from Sept 30th, and we don't see the peak anymore. Pink and Violet are showing ground motion.

(2) Dashed curves are left and right osems from September 10th before the sat amp was changed, the 6.18Hz peak is present. Plain blue and red are from September 27th, after the sat amp was changer, the peak is a lot reduced.

From those plots, it looks that changing the satellite box reduced the peak by a large amount.

We would need to get the ISI to the requirements, as shown on dark blue of first pdf, and do the same measurement, in order to conclude that it entirely fixed the problem.

New RM2 Tip Tilt set up and ready for install in HAM1

Joe Gleason, Pablo Daveloza, Keita Kawabe

We attempted to balance the RM2 Tip Tilt optic by shifting the wire clamp mounting block in the optic holder but were unable to do so at the limit of its range.

We elected to install the optic in a new suspension assembly from the set for HAM6. The new assembly also required a large change to the wire clamp positions but we were successful in getting it balanced. We performed the remaining setup on the assembly and bagged/stored the assembly in the temporary clean room outside HAM2.

HAM1 in-vac work : mirror was flipped in a tip-tilt and too big pitching was found in the other

[JoeG, Keita and Kiwamu]

We continued working on the HAM1 installation this afternoon.  All the optics except for the detectors are now on the table including the newly installed QPD sled. We removed the counter weights although didn't check the table level yet.

Besides, there are two (unhonourable) highlights to mention from today's HAM1 incursion.

1. The mirror of a tip-tilt (RM1) was found to be backward. So we flipped it to the right direction in situ.
2. The other tip-tilt (RM2) started showing a too big pitching

 

A big pitching in a tip-tilt (RM2):

After the removal of the counter weights we went through the alignment process again in the in-vac detector path. The alignment needed a slight touch mainly in pitch. Then we found that RM2, which is a tip-tilt , showed a large pitching so that the reflected beam went too low. Joe tried to correct it by screwing the bottom 8-32 screw further in. This screw is designed such that as we screw it in, the center of its mass changes the pitching of the whole holder (so as to lower reflected beam). We wanted screw it in further but however the screw was too long and in fact it was already touching the back cage. Keita brought a shorter screw which is 8-32 x 1" and we tried this. However sadly it still hit the back cage because of too large pitching. Joe translated the upper blades to the front to separate the back cage and holder further apart, but this didn't fix the issue. Note the mirror holder was picthing in the same direction even without the screw.

According to our inspection, the clamping point of the wire on the left wire clamp (when looking from the front) on the mirror holder is too close to the back side. Probably about 1 mm off from the center toward the back side. The other side looked also close to the back side but not as big as the left side. At the moment we think this gives such pitching in the mirror holder. Pictures of the clamping point for both left and right sides are attached below. You can see how they are clamped through a rectangular window of the side cage. We have no idea of if it has been like this or when and why this happened. Adjusting the clamping point is certainly beyond what we can do in the chamber because it probably involves with all the alignment and adjustment process. Therefore we removed the tip-tilt our of the chamber. It is now in the clean booth nearby HAM1.

Plan :

 Next week we will bring another tip-tilt which was assembled for HAM6 and swap the bad one with it. Hopefully we can smoothly place the tip-tilt and move on to some measurements for checking the mode matching.

The wire not being centered in the clamp is intentional.  This is because with the wire centered I found that the tip-tilt mirror tips backwards and it will require some pretty heavy counter balance screw to correct its pitch.  At least this is my experience.  I had started with the wire centered and faced this problem.  I solved it by displacing the wire and then sliding the clamps on the mirror holder to coarse adjust the pitch angle.