Sheila, Alexa

We noticed that the HEPI tidal feedback to the ETMs was not working. We found that the ISC MON outputs were off, the ISCINF_LONG offsets were off. In addition the ETMY ISCINF gain was zero and the ETMX ISCINF gain was 1000; the nominal gains should be 1. This is now in the guardian.

We are trying to make sense of what we see during the CARM offset reduction. We believe that we are at a lower CARM offset than we estimated given our power build up.

When our power build up is ~120 (wrt single arm, as measured by the TR QPD - Sheila is checking the normalization), REFL_DC is already at ~50% of its max power, and it looks like REFL_9I is indeed already within its linear range. However, at that point we should already be close to ~500 x single arm power (or half of the total build up, nominally 1000 x single arm). POP_DC shows only a modest factor of 2.5 increase with respect to only sidebands in the recycling cavity, it should be higher than that. 

This would explain while we couldn't further increase the CARM offset, as the TR signals are becoming flat, and why we couldn't keep using the same AS WFS signal in loop, as it is changing sign at low CARM offset (  see Dan's model ).

We will try to figure out why this is happening (are we simply misaligned? low carrier recycling gain? loss in the arms?...).

The positive message is that there is no point in trying to further reduce the CARM offset in this state..so we are done with that.

Kiwamu posted  these simulation plots  as a comparison, and  LLO log 12765  is an example of the LLO sequence.

ASC model (ASC_MASTER.mdl) and the end station ALS model (ALS_END.mdl) were modified and installed as a test to accomodate the TMS actuation and the ITM camera sensing in ASC.

Now ALS WFS DOF3 (which is used for ITM camera) goes to the ASC, and the ASC output matrix can act on TMS.

Relevant MEDM screes were updated.

h1guardian reboot: Dave, Patrick

At 10:06 PST I rebooted the h1guardian0 machine to test that all the nodes started automatically. The reboot proceded normally and all the guardian nodes did start automatically, SUSMC1 node was slightly delayed relative to all the other nodes. For reasons currently unknown the restart crashed the conlog master. Patrick restarted the conlog.

Model Changes: Keita, Daniel, Dan H, Dave

The following models were restarted with new code: h1susetmx, h1iscex, h1hpietmx, h1susetmy, h1iscey, h1hpietmy, h1asc, h1omc, h1susomc

Frame Writer Minute Trends Offload: Jim

h1fw0 has been busy over the past day copying its raw minute trends from the SSD array to HDD. Many restarts of h1fw0 are attributed to this loading.

h1susetmx snap files: Dave

For reasons unknown many old snap and log files in the directory target/h1susetmx/h1susetmxepics/burt/ were deleted between 10:00 and 11:00 PST this morning. This included the safe.snap symbolic link. Therefore the 11am restart of h1susetmx did not burt restore to its safe.snap, rather to the snap file created at the shutdown time. I restored the safe.snap link. Investigation continuing.

Partial loaded Filter Module Files: Dave

The following systems were discovered to have partially loaded filter files, I performed a "load all coefficients" on: h1psliss, h1susprm, h1sussrm, h1oaf, h1lsc, h1omc. The model h1asc took care of itself after it was restarted.

SVN local mods: Dave

The following front end source files have local modifications:

                           lsc/common/models/lscals.mdl  Tue Mar 11 21:57:37 2014    M      
                                lsc/h1/models/h1lsc.mdl  Mon Oct 27 15:40:01 2014    M      
                              omc/common/models/omc.mdl  Tue Dec  2 13:16:29 2014    M      
                                omc/h1/models/h1omc.mdl  Tue Dec  2 12:32:27 2014    M      
                           psl/common/models/psldbb.mdl  Fri Jan 10 19:19:47 2014    M      
                           psl/common/models/pslfss.mdl  Fri Nov 21 14:12:02 2014    M      
                           psl/common/models/psliss.mdl  Tue Nov 18 11:47:45 2014    M      
                           psl/common/models/pslpmc.mdl  Fri Nov 21 14:13:54 2014    M      
                             psl/h1/models/h1pslfss.mdl  Wed Sep 17 14:54:45 2014    M      
                             psl/h1/models/h1psliss.mdl  Fri Nov 21 14:16:00 2014    M      
                             sus/h1/models/h1susomc.mdl  Tue Dec  2 12:32:25 2014    M 

the following guardian files have local modifications:

M       common/guardian/ALS_DIFF.py
M       common/guardian/ALS_COMM.py
M       common/guardian/ALS_ARM.py
M       common/guardian/IMC_LOCK.py
M       h1/guardian/lscparams.py
M       h1/guardian/ISC_DRMI.py
M       common/guardian/LSC_PRMIsb.py
M       common/guardian/LSC_CARM.py
M       h1/guardian/lsclib/prxy/carrierlock.py
M       h1/guardian/lsclib/pdOffsetNull/pdOffsetNull.py
M       h1/guardian/lsclib/prmi/sidebandlock.py
MM      h1/guardian/LSC.py
M       common/guardian/OMC_LOCK.py
M       h1/guardian/omcparams.py
M       common/guardian/SUS.py
M       common/guardian/susconst.py
M       common/guardian/SUS_TMS.py
M       common/guardian/SUS_BS.py
M       h1/guardian/SUS.py
M       common/guardian/ifolib/CameraInterface.py
M       h1/guardian/H1ECATX1PLC2.py
M       h1/guardian/H1ISCEX.py
M       h1/guardian/CSD_LoadDatabase.cmd

DMT Broadcaster: Dave

Checked all DMT channels are in the DAQ. Found to my chagrin that two channels were duplicated in the broadcaster list. H1:PEM-EX_MIC_VEA_MINUSX_DQ and H1:PEM-EX_MIC_VEA_PLUSX_DQ. I have removed the duplication which will be applied on the next DAQ restart.

Alexa, Sheila, Dan, Dave O.

Stefan had reported that the original SRM ASC wfs had been oscillating post TCS work (alog 15343). For SRM we had used AS_A_RF36_I as the error signal with a gain of P, Y = 0.3, 1.2. We compared this with REFL_B_RF45_Q error signal, which at one point Livingston had been using, and found this actually appeared to be a better signal. We were able to close the yaw loop with a gain of 4. I did not see any oscillations with this loop closed for about 10 minutes; and it appeared to bring the build up back whenever I misaligned SRM. We tried closing the pitch loop, but have not suceeded yet. We tried a gain of -4 and 4, which caused the loop to oscillate. I reduced the gain of -1, and did not see oscillations, but was not able to recover the build up with an SRM alignment.

For now, we decided to move on and try locking. There is still more work to be done in closing this loop. I will not update the guardian yet.

Alexa, Dan, Sheila

We found the BS ISI ST2 watchdog was tripping when the DRMI was acquiring lock; big transients in the MICH control signal would show up in the ST2 GS13s and saturate the inputs.  After some dataviewer'ing, we found that these transients are always there, but today they were large enough to hit the watchdog threshold.  We suspected the GS13 gains had changed, and conlog said that yesterday the 'Gain' filter (FM4) on the BS ISI GS13INF filter banks was turned on.  (We suspect that someone turned these off during the SEI work today?)  We turned them back on; the problem seems to be fixed.

None of the other BSC chambers have these filters on, but it looks like we need them for the BS, for now.

Here are two plots showing the ideal behavior of some DC signals and REFL9 signal during reduction of the CARM offset. They are computed by optickle with the designed optical parameters except for the modulation depths which are now 0.17 rad and 0.3 rad for 9 and 45 MHz modulations respectively.

Attachment 1:

A plot of some DC signals as a function of the CARM offset. TRX (show in red) is normalized by the single arm power. It reaches 1350 with zero CARM offset, indicating that the recycling gain is about 41. REFL_DC (shown in cyan) is normalized such that it is unity when the CARM has a large offset. The same normalization is applied to POP_DC (shown in brown) as well. The black curve is derived simply by sqrt(normalized TRX + normalized TRY).

Attachment 2:

A plot of REFL_DC, AS_DC and REFL9 demodulated signals as a function of the CARM offset. AS_DC is in mW while REFL_DC is in Watts. The demod signals are in an arbitrary unit.

7:50 Jeff in LVEA loading 3IFO storage container

8:22 Keita to EY working on green WFS

8:26 Fil and Aaron to EY working on PEM cabling

8:32 Mitch to west bay 3IFO storage work

8:37 Excavators on site

8:54 Karen to EY

8:55 Betsy to west bay 3IFO work

9:01 Cris to EX

9:03 Corey to squeezer bay 3IFO work

9:06 Sudarshan to EX, EY PEM work

9:10 Keita done

9:34 Jonathan fixing remote login system

9:41 Dave restarting guardian

9:42 Fil pulling HEPI server

10:09 Mitch done

10:10 Karen done

10:20 JoeD checking forklift batteries in LVEA

10:23 Doug to LVEA for OpLev inspections

10:36 Dave to LVEA for tour

11:04 Jonathan done

11:05 Kyle done

11:10 Sheila to optics lab and squeezer bay for cleanup work

11:19 Jeff done

11:30 Sudarshan to EX

11:48 OpLev crew to EX

12:00 Corey done

12:03 Dave restarting DAQ

12:34 Dave restarting OMC model

14:40 Sudarshan done

15:48 Trenching work between OSB and VPW is complete and patched.  Road to EY is reopen.

Sheila kind of requested this (I may have pushed for it), she feels confident she can turn it off if the commissioners feel it's causing problems. Tomorrow, I'll work on a python script for the commissioners to turn this on for all chambers, to make this easier, as the HEPI MEDM screens are a bit labyrinthine.

Andres R., Mitch R., and Jeff B.

    We completed the loading of the HAM ISI 3IFO Storage Container #3. The suspensions would not fit as specified on page #3 of D1300146. We rearranged the suspensions so (1) the TMS Upper Structures were centered and moved as far towards the edge as could be, (2) the Quad sleeves are still in the center of the container but two had to be rotated 90° so they would stack, and (3) the AC baffles were placed around the edges at 45°, 135°, 225°, and 315°. See photos below. We encountered no other serious issues. 

I updated the input matrices for ETMY and the BS ISI's this morning. This required redoing the isolation loops for both chambers, so I worked through those as well and re-installed all the filters. Afterwards, both chambers came right back up. Tomorrow, I'll try to do some performance comparisons for tonight and last night. In general, the loops are 30-35hz UGF's, and not particularly aggressive.

    These are the latest transfer function and Spectra data plots for 3IFO Quad-08 found in the repository.  

Dan, Dave

Today we rebuilt and restarted the OMC and OMC-SUS models to incorporate Livingston's changes to the ASC for the output mode cleaner.  These changes add outputs from the OMC model that pass ASC control signals to the OMC SUS (L,T,V,P,Y,R).

We've also incorporated a change from Livingston to the OMC master model (userapps/release/omc/common/omc.mdl) which adds a software trigger to the OMC length control signal.  This trigger shuts off the output to the HV PZT (OMC PZT2) when the HAM6 trigger is closed.  The input signal to this software trigger is the output of the PZT1_MON_DC channel; this acts as a readback for the shutter controller state.  The idea is that when the HAM6 shutter controller detects an input condition (light level above threshold), we should disable the length control signal to the OMC.  (Note that this change is somewhat redundant with the input trigger to the OMC length control signal, which enables the OMC LSC when the DCPD sum is above a threshold.)

Awkwardly, the output of PZT1_MON_DC is different between the two sites.  At H1, the PZT1_MON_DC readback out of the PZT driver box is -20V when the trigger is in the nominal/open state, and 0V when the trigger is tripped/closed.  At L1 it's apparently -5V when open and 0V when closed.  Furthermore, at H1 we calibrate the output of PZT1_MON_DC to reflect the voltage that is delivered to the PZT in the chamber: 10V in the open state, 0V in the closed.

The punchline is that I've flipped the polarity of the software trigger to work with the conditions at H1, and I've changed the threshold to be 5V instead of -3.9V.  This means the H1 version of the OMC master model is different from L1 - see the attached figure.  We'd like to understand why the output of the PZT1 DC monitor is different between the sites, but for now we'll need to remember that the master model here at H1 is slightly modified.  I have not committed these changes to the SVN.

J. Kissel

In summary:
(1) Turn on X, Y, and Z sensor correction for HAMs 2 and 5, using the standard Hua Filter scheme (see T1200285), with tuned gains.
(2) Use LLO's M1 OSEM Damping filters and gains.
(3) Turn off optical lever damping so we don't have worry about maintaining optical levers to as great care.

-------

This continues (and hopefully resolves) the study of why PR3 and SR3 (both HLTSs) are angularly noisy, began by Kiwamu (see LHO aLOG 15048), and continued in a prior aLOG by me (see LHO aLOG 15154). I had started today thinking that I would do the usual full modeling suite, and this time include the optical lever damping. But after a little bit of exploring, I found that the L1 HLTS, H1 PR3, and H1 SR3 were using in various, completely different damping schemes, the performance of the optical levers are radically different, so a noise projection would be difficult, and the L1 vs. H1 HAM ISIs perform significantly different. So, since a "representative" model seemed impossible, as did the thought of making an individual model for all four suspensions and comparing, I've just spent the time gathering proof of what we need to do to make them much better. Once we get all of the above three steps completed *then* I'll make a full model suite of the performance.

Here's the details explaining how I can to these conclusions. They're supported by the first and only attachment.
(3) Turn off optical lever damping.
    Pages 1 and 2 of the attached show the wide variety of performance on the optical levers. Page 3 and 4 show the H1 the levers are in loop, but only with a bandwidth from 0.4 to 1 [Hz] (see design for SR3 in LHO aLOG 14719). There seems to be some effort toward rolling off the noise, but it seems quite unrelated to the actually noise performance of the levers at high frequency.
    LLO *had* used optical lever damping sporadically on L1 PR3, but they're currently not using it and haven't since Oct 17 2014. Given that the damping is so much strong and the input motion is so much smaller, this makes sense that its not needed. Further -- even with L1 SR3 aligned, the location to which, presumably, the optical lever has been centered -- the performance of the optical lever spectra is not limited by residual ground motion of the optic. So it's most certainly unusable for control. 
    Including optical levers in the local damping scheme complicates the remaining dynamics of the suspension (and perhaps more to the point, the subsequent modeling of it), and getting used to relying on them means they'll be left on and most certainly reinject noise above their bandwidth unless the loops are custom tailored to the ever-evolving optical lever noise. So if we can achieve the same level of local damping with the top mass OSEMs, and improve the performance of the ISIs, let's do it. 

(1) Turn on X, Y, and Z sensor correction for HAMs 2 and 5, using the standard Hua Filter scheme (see T1200285), with tuned gains.
    Pages 5 through 7 compare the performance of the HAM2 and HAM5 ISIs, highlighting the degrees of freedom which contribute to L, P and Y at the optic. 
    Remember, the L at the suspension point is the dominant contributor to L *and* P at the test mass, at all frequencies (see pgs 5 and 33 of the second attachment to LLO aLOG 7907). In turn, X and RY (for PR3) and Y and RX (for SR3) are the dominant contributors to L at the suspension point. Y at the optic is all Y at the susp. point, which is all RZ of the table.
    Though I'm not sure what the H1 HAMs have worse performance than the L1 HAMs between 2 and 8 [Hz] (that should be investigated further), I certainly know that the *drastic* difference between 0.3 [Hz] and 1 [Hz] is because LLO has sensor correction for all DOFs turned on. Poking around at LLO, I've found that the sensor correction is nothing particularly fancy -- it's just the standard Hua filter scheme, with a single, gain only Match filter at the output to tune better match STS gain to the displacement sensors (those gains are a correction of ~10-20%, matched to a ridiculously high precision [where its unclear if the precision is needed]). HAM2 uses the HAM2 STS (STS A), and HAM5 uses the HAM5 STS (STS C), as expected.
    At the first L and P resonances of the HLTS, there's a possibility for the following improvement if we get to LLO's level of isolation:
Frequency [Hz]   Table DOF      Performance Ratio
    0.64          HAM2 X       6.23 / 0.11 = 56.6
                  HAM5 Y       5.29 / 0.08 = 66.1 
    0.74          HAM2 X       1.87 / 0.03 = 62.3
                  HAM5 Y       1.42 / 0.02 = 71.0
and as we know by now, its these lowest resonance frequencies that dominate the RMS motion of the optic.
    All this being said, except for between 0.2 [Hz] and 0.6 [Hz], LLO is kicking the snot out of the "requirements." Nice job! I'm very confident that we can do just as well here at LHO. The trick will be to get the HAM2 and HAM3 sensor correction up at the same time, so that we don't introduce and relative low frequency noise in the recycling cavities.

    P.S. There're some pretty nasty sharp features and associated harmonics in the L1 HAM5 ISI's RX and RZ spectrum ... we should get that fixed -- they're obviously electronic, particularly ugly, and might affect pulsar searches.

(2) Use LLO's M1 OSEM Damping filters and gains.
    Pages 8 and 9 highlight the DRASTIC difference in damping loop filters. I hesitate to call the H1 HLTS filters a "design," because I know they were copied from the QUADs (hence the 0.43 [Hz] and 0.56 [Hz] resonant gains in the L and P filters, respectively). There's no reason at all we shouldn't just switch to the LLO design immediately -- these aren't under global control so we need not worry about changing any global control transfer functions, and though I haven't modeled it (yet) the increase in gain at just about all frequencies, especially what's focused at the *actual* first L and P modes of the HLTS. With the switch, we would get a factor of 16.2 increase in gain at 0.75 [Hz] in the L loop (which presumable will hit the same mode in P as well), and a factor of 44 increase in gain at the first, 1 [Hz], Y resonance.

With steps (1) and (2) complete, that means we can expect to improve the Y and P motion at the optic, at the main resonances by as much as three orders of magnitude.