Displaying reports 65661-65680 of 83043.Go to page Start 3280 3281 3282 3283 3284 3285 3286 3287 3288 End
Reports until 09:06, Tuesday 14 April 2015
H1 SEI
corey.gray@LIGO.ORG - posted 09:06, Tuesday 14 April 2015 - last comment - 09:27, Tuesday 14 April 2015(17857)
BRS Switched OFF ~9:00am

Jeff/Andres will be going to EX, so we turned the BRS Switch OFF (with help from TJ & Jim W).  We will turn them back ON when incursions are complete probably after Maintenance since we have winds hovering around 20mph already.

Comments related to this report
thomas.shaffer@LIGO.ORG - 09:27, Tuesday 14 April 2015 (17858)

Reminder to Operators:

If the BRS Sensor Correction is being used and someone needs to go to EX, the operator needs to turn OFF BRS Sensor Correction and change the appropriate filters.

I have a script that will do this in /opt/rtcds/userapps/release/isi/h1/scripts/

To use it, navigate to this directory and then type "python BRSswitch.py OFF" or if you want to turn it back on "python BRSswitch.py ON"

If you forget, you can -h it and it will help you out.

H1 AOS (ISC)
edward.daw@LIGO.ORG - posted 08:21, Tuesday 14 April 2015 (17855)
Instructions for acquiring broadband power spectra and cross correlation / coherence data from OMC DCPD, REFL_AIR Q90
Ross Kennedy & Ed Daw

Instructions for acquiring 100kHz bandwidth ASD, cross correlation, and cross spectral density measurements with 100kHz bandwidth.
1. Check that the LVEA SR785 in the LVEA is hooked up to the OMC DCPD whitening preamplifier pick-off (channel A) and the long RG-58 cable back to the REFL 
electronics (channel B). I left it hooked up when we departed, but it might have been disconnected, I guess. Check also that the GPIB and wireless internet box are connected and powered up.
2. On a control room machine, cd to /ligo/home/controls/edaw_work/hfross
3. Do ./SR785broadscan
- this generates a sequence of measurements covering DC-102.5kHz in 16Hz bins. There are four resulting plots, in order, ASD from the OMCDCPD1, ASD from REFLAIRQ90, cross correlation density from both ports (note that this is per Hz over 16Hz bins, so multiply by 16 to obtain cross correlation on the usual 0-1 scale), PHASE of the cross spectrum
between OMCDCPD1 and REFLAIRQ90 (mainly useful to see the noise in the phase disappear at frequencies where there is extensive cross correlation. 
Results appear in the saved_data subdirectory. Text files of data are saved there too for more detailed information on line frequencies.
Let me or ross know if this doesn't work - we can probably help fix it.
H1 ISC (SUS)
sheila.dwyer@LIGO.ORG - posted 22:55, Monday 13 April 2015 (17854)
Angle to length coupling for ETMs, beam diverters, wind, rotation stage

Alexa, Sheila. Evan, Daniel Koji

Unfortunately, all of these promising developments happened during a lock where the ETMY ESD was tripped, untripping it breaks the lock.  Evan has edited the guardian so that it will not move past ALS unles the ESD is on, so this should not happen to us again.  

Sadly, the wind  started gusting to 30-35 mph while we were reseting the PUM watchdogs, and is forecast to stay that way for about 24 hours.  We have locked with these kind of windspeeds before, but today we are having difficulty, perhaps because the ground motion below 1 Hz was not small even before the wind started.  The BRS is on at end X with broad low frequency sensor correction, however this storm seems to be mostly along the Y direction.  Evan has also increased the common tidal bandwidth again (0.08 now).  We've ben keeping ALS locked for 10-15 minutes.  

Images attached to this report
H1 SYS
daniel.sigg@LIGO.ORG - posted 20:45, Monday 13 April 2015 (17853)
Timing System Screens

We finally have a complete set of medm screens for the timing system.

There are a lot of red indicators due to the fact that the svn revision numbers are reported as zeroes by the DuoTone and IRIG-B slaves. There is no indication that we are not running the firmware we think we do, but we can't really check this.

The EX fanout reports a VCXO range error which has been there for a long time and is most likely is due to a busted readback.

All other master, fanouts and slaves are reporting a green status.

Images attached to this report
H1 CAL (CAL, ISC, SUS)
jeffrey.kissel@LIGO.ORG - posted 17:08, Monday 13 April 2015 (17847)
2015-03-10 to 2015-04-06 DARM Open Loop Gain Transfer Functions
J. Kissel, S. Dwyer, E. Hall, K. Arai, K. Izumi

I'm embarrassed to say I'm overwhelmed by the wealth of open loop gain transfer functions (OLGTFs) that have been taken recently. But, there's also a ton of stuff to explain, so I summarize comparisons and information from the 3 OLGTFs that were taken prior to this weekend here. More to come on this past weekend's new data.

Summary Points: 
- With a "streamlined" matlab model (similar in content to, but separate from the Noise Budget DARM loop model) we can predict the following DARM OLGTFs (measured between 5 and 300 [Hz]):
2015-03-10, Prior to DARM Loop Shape Modification LHO aLOG 17153
2015-04-02, Post DARM loop modification LHO aLOG 17642
2015-04-06, Post DCPD Analog Electronics Compensation Correction LHO aLOG 17710
to within 10% in magnitude and 5 [deg] in phase (between 5 and 300 [Hz]), with the following uncertainties (determined by the standard deviation of the model parameters for these three comparisons):
     - DC optical gain of 1.1e6 +/- 8%
     - residual, [unknown / unaccounted for] time delay of 93 +/- 30 [us]
- The DCPD Analog Electronics Compensation confusingly did *not* affect the frequency dependence of the OLGTF between 2015-04-02 and 2015-04-06, even to the 10-20% level Koji suggests. As of now, based on these measurements alone, I argue that the lack of discernible change in the OLGTF suggests that we do *not* need to make any correction to our CAL-CS front end calibration.
- Just because I can model the open loop gain TFs to this uncertainty level does *not* mean the overall DARM calibration has this uncertainty. We still have a (potentially) large variation in ESD actuation coefficient due to charge, a (potentially) large uncertainty in the DARM coupled cavity pole frequency, a (potentially) large optical gain fluctuation from lock to lock, and (potentially) large discrepancy between the real actuation strength and what we've measured, and all things of which we haven't realized.

Detail Points:
--------
- Kiwamu had put together a "simple" model of the DARM loop when he'd updated the DELTA L EXTERNAL calibration in the CAL-CS front-end filters after the second-to-last time the DARM loop shape was changed (see LHO aLOG 17151). As he mentions in his aLOG, this code lives here:
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Scripts/DARM_OLTFGTF_LHOaLOG17153.m
That model had included
    Actuation Function
    - The QUAD SS Model that have the current foton filter file's damping filters engaged with gains that are hard-coded into the generate_QUAD_Model_Production function to gather the necessary damped SUS transfer functions in [m/N], i.e. the output of 
    /ligo/svncommon/SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Production/generate_QUAD_Model_Production.m
    using the 
    /opt/rtcds/lho/h1/chans/H1SUSETMX.txt
    foton file.
    - An assumed DAC gain of 2^18 / 20 [V/ct].
    - The UIM analog electronics chain using 
    /ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/make_OSEM_filter_model.m
    all parameters of which are "as designed" and not measured. This turns the [N] of drive at the UIM into [ct] of drive at the output of the ETMX_L1_LOCK_L bank.
    - The ESD analog electronics chain using a simple, linearized model of 2*alpha*Vbias*40^2, where 40 is the range of the DAC, Vbias is the bias voltage, in units of the DAC [V], and alpha is the force coefficient. He uses the force coefficient that has been confirmed by measurement to be (2.0 * 1.417)e-10 = 2.834e-10 [N/V^2]. (see LHO aLOG 16843) 
    - The ESD driver's single pole filter
    - The correct hierarchical filters from the current foton file (same as above), with known gains grabbed from conlog.
    The DARM filter
    - Loaded in from the H1OMC foton file from the filter archive,
    /opt/rtcds/lho/h1/chans/filter_archive/h1omc/H1OMC_1110098950.txt,
    with known gains from conlog.

    The Sensing Function
    - Assuming the Actuation and DARM DC gains are correct, the remaining scale factor needed to match the OLGTF model to the measurement is what is used for the interferometer's optical gain, in [m/ct]
    - A single-pole zpk filter, with the pole at 389 [Hz]

    Time Delay
    - An overall true time-delay to account for *all* the high frequency behavior like anti-imaging and anti-aliasing filters.

I've used this model as a template to get started, but I've made the following changes to (a) be able to compare many OLGTFs against the model that best represents the DARM loop at that time, and (b) include the now-better-known high-frequency effects:
(1) Pulled out the hard-coded parameters of the model, and put them in a separate function identified by their GPS time,
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Scripts/
H1DARMparams_1109994128.m
H1DARMparams_1111998876.m
H1DARMparams_1112399129.m
(2) I've modified the filter files chosen such that both the OMC *and* the SUS are pulling from the filter archive, not the live data. This will be come relevant later when we track changes in UIM / TST crossover, or when we begin using all stages like LLO has.
(3) I've now included both the analog and digital anti-aliasing in the sensing function, and the analog and digital anti-imaging in the actuation function. The digital AA and AI filters are the same, from the function
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/S7/Common/MatlabTools/iopdownsamplingfilters.m
and the analog AA and AI filters are the same, taken from .mat file inherited from the 40m, which has been pruned and now lives in
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/S7/Common/MatlabTools/analog_65k_AAAI_filter_response.mat

(4) I've included the known time delays:
Sensing: 1 IOP Computation Cycle (65k) + 1 OMC Computation Cycle (16k)
Actuation:1 SUS Computation Cycle (16k) + 3-Cycle IOP Error Checking (65k) + 1 IOP Computation Cycle (65k) + Zero-order Hold Delay (1/2 a 65k cycle)
(which total 205 [us]) and created a new parameter for the "unknown" time delay, which is fit to make the high-frequency phase flat.

Known remaining flaws in the model:
- Mismatch in digital compensation for analog whitening or pre-amps of the DCPDs -- but this should now be *much* better than before (see LHO aLOG 17650)
- Mismatch in digital compensation for analog whitening of the SUS UIM coil driver and now the ETMY ESD Driver filter 
    -- Measurements have shown that the UIM driver agrees quite well with the model (see LHO aLOG 4495), but this hasn't been confirmed for these SUS individually and/or after their increase in range (Integration Issue 762).
    -- The "temporary" ESD low-noise filters (E1500164) were compensated with their designed poles and zeros, I don't know how well they're matched.
- The model uses 389 [Hz] for the DARM coupled-cavity pole, but this is a modelled value from the L1 IFO's losses (see LHO aLOG 15923). Our losses are larger, so we expect our cavity pole frequency to be higher. More to come from Paul and Daniel on this. The data out to 1 [kHz] from over the weekend should also help with getting a measured confirmation.

This model is a function which takes in the parameter files, is called 
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Scripts/H1DARMmodel_preER7.m,
and returns the modelled and measured open loop gain as well as every single possible thing you could possibly ever want out of the model in a parameter structure (including the things that are independently computed in the model itself, like the full actuation function and the full sensing function).
This model can then be looped over, which I've done with the function
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Scripts/CompareDARMOLGTFs.m

I *hope* that this makes it much easier to compare a new DARM OLGTF against others as we take them.
Non-image files attached to this report
LHO VE
bubba.gateley@LIGO.ORG - posted 16:52, Monday 13 April 2015 (17852)
Beam Tube Washing
Scott L. Ed P. Chris S.

The crew cleaned 70 meters from last single door to mid station on X-1. Crevice tool cleaning remaining on that section. 

Beam tube pressures monitored by control room operator during cleaning operations.  
H1 AOS
jim.warner@LIGO.ORG - posted 16:15, Monday 13 April 2015 (17850)
An object lesson in blind complementary filter design, or: How I learned to start worrying

Last week I tried exporting some of the blend filters mods that I had developed at ETMX, but found that at least one of the blends didn't work. Today I worked on figuring out why.  I started by doing an ugly hack of Jeff's plot_current_blends script so I could look at the original LLO  blends in complementary form. When I used the hack to look at what I had installed, it became immediately clear why my blend didn't work. In the attached image, I show the complementary version of the "bad" blend (solid lines) and a "good" blend. The good blend is what is currently running on st2 on all of the BSC's in X,Y,Z and RZ. It's a modification of a 250 mhz blend that we stole from LLO (they run a similar blend). The bad blend is a modified version of the 01_28 blend we use on the HAM ISI's. You can see that at .4 hz I managed to introduce a notch ( in the solid red line) that did all kinds of band things to the plant.

This happened because I was designing in foton (blind), and couldn't see the complementarity of the blends from there. I thought I was safe because I was making small adjustments and was trying minimize any phase wobbles around the blend frequency. Turns out that is not enough. I think fixing the complementarity will be relatively simple,  the first image in my alog  17790 shows why I would like to get this to work, roughly an order of magnitude reduction at 1 hz, with some low frequency injection.

The amazing part is this blend runs on ITMY and ETMX.

The 2 attached pdf's are the original blends (1st pdf) and modified blends (2nd pdf) for both stages X, Z, RY, RZ , shown in both installed and complementary versions.

The successful mods I made are adding elliptical filters to the St1 90 mhz Z blend (alog 17702), a more effective elliptical to the St2 250 blends (alog 17488) and an elliptical to 750mhz St1 RZ cps blend. I haven't found the to do much good, but it doesn't do any harm that I've seen.

Images attached to this report
Non-image files attached to this report
LHO VE
kyle.ryan@LIGO.ORG - posted 16:07, Monday 13 April 2015 (17851)
HAM6 almost recovered
Kyle, Gerardo 

We switched HAM5/6 annulus pumping over to the small annulus ion pumps and removed the pump carts -> The 500 l/s "main" ion pump was valved into HAM6 but we are leaving the turbo pump pumping in parallel with it over night 


- Commissioners -

HAM6 high voltages components (picomotors, PZT and fast shutter) can be left energized/enabled without monitoring HAM6 pump curve now.
LHO General
corey.gray@LIGO.ORG - posted 16:07, Monday 13 April 2015 (17837)
Ops DAY Summary

Went through an initial alignment after the PSL incursion, but had issues getting the full interferometer to lock up.  Commissioners had a few attempts which have come close to DC Readout this afternoon, but H1 dropped out at various steps.   They're continuing to get H1 locked UP.

Summary of Day's Activities:

H1 SUS
betsy.weaver@LIGO.ORG - posted 15:23, Monday 13 April 2015 - last comment - 15:26, Monday 13 April 2015(17848)
SUS SDF update effort continued

Today, I restored the ITM misaligned TEST_OFFSET and TEST_GAINs which I found to be showing as diffs in SDF - Sheila had been playing with them last week but said they should be restored.  Snapshots of the ITMy "was" and "now" (aka good) values are attached.

 

Turned ITM R0 OPTICALIGN zeroed offsets and inputs off - these are never used and are just confusing when found on.

 

Cleaned out BIO/COIL/TEST_SW2 and LOCK_SW2 changes like has been ongoing across all SUSes.

Images attached to this report
Comments related to this report
betsy.weaver@LIGO.ORG - 15:26, Monday 13 April 2015 (17849)

While I was SDF'ing, I found both ETMs with R0 (reaction) chain YAW offsets enabled.  See pix below - My guess is that commissioners will want to turn these off.  I also think these loops should have the inputs turned off for good (like I did with the ITMs) so as to not be confusing later.

As posted, I've been finding fishy settings on ETMs recently - maybe someone picked a poor snapshot file when restoring last week...?

Images attached to this comment
H1 CDS
david.barker@LIGO.ORG - posted 14:44, Monday 13 April 2015 (17846)
ASC RFM IPC Errors

Rolf, Jim, Dave:

after removing the LSC RFM receive errors completely last week, I noticed that the ASC is getting receive errors from the ALS models at the end stations at a very low rate.

The rate of error is one every 8 to 10 hours. The return of the errors can be tracked back to the ALS model changes made last Tuesday 07apr2015 during maintenance. A trend of the ALS CPU usage shows a difference in signature (attached plot shows last 2 weeks of trends) starting last tuesday.

To remind everyone, when the end station ISC was split, the ALS is the "slow" component, so RFM errors would not be entirely unexpected from this sender.

Images attached to this report
H1 PEM
robert.schofield@LIGO.ORG - posted 13:05, Monday 13 April 2015 (17845)
Beam Tube Motion In Wind - No Insulation

An understanding of beam tube motion as a function of wind speed is important in predicting scattering noise from the beam tube baffles and in deciding if we need to re-insulate the beam tube. This data was taken during the windstorm on Apr. 11, 2015 at baffle #96 (near the power maximum for the diffracted light from the pattern on the original optics), near the first double doors towards the CS from MY. Figure 1 is a photo of the accelerometers attached to the beam tube, and Figures 2-4 show the motion along the different axes at 3 different wind speeds (9, 18 and 24 MPH). As a first guess I would expect peak amplitudes to increase roughly with wind speed to the 3/2 power (wind power goes as the cube), and, very roughly, it seems consistent.

Raw data archive

Non-image files attached to this report
H1 PSL (PSL)
peter.king@LIGO.ORG - posted 12:23, Monday 13 April 2015 (17843)
TTFSS work

Today's quest to increase the bandwidth of the FSS involved the following steps:

 

The file NONOTCH1.TIF is the open loop transfer function with no notches installed.

Unfortunately the NPRO noise eater was oscillating for this measurement.

 

The file NONOTCH2.TIF is without the NPRO noise eater oscillating.  One can see

the ~760 kHz resonance that the notch was installed for originally.

 

The file 150PF.TIF is the open loop transfer function with just the one notch installed.

That notching being the one with 220 uH and 150 pF.  The unity gain frequency is a little

over 300 kHz here.

 

The file 120PF.TIF is the open loop transfer function with the 150 pF capacitor replaced by

a 120 pF capacitor.  The rationale being moving the notch frequency higher might still attenuate

the 760 kHz resonance enough and allow the gain to pushed a little higher.  This introduced

either another resonance or did not sufficiently suppress the 760 kHz one.

 

The file RESTORE1.TIF shows the open loop transfer function with the TTFSS restored to its

original state.

 

For all measurements the reference cavity transmission was ~1.45 V, the fast gain was 18 dB

and the common gain was 22 dB.

 

 

Ed, Peter
 

Images attached to this report
H1 PSL
corey.gray@LIGO.ORG - posted 10:36, Monday 13 April 2015 (17841)
Operator Weekly Post Of PSL Checklist

Many items are skewed since there is currently activity in the PSL this morning.

Laser Status: 
SysStat is good
Front End power is 31.7W (should be around 30 W)
FRONTEND WATCH is RED
HPO WATCH is RED

PMC:
It has been locked 18 minutes (should be days/weeks)
Reflected power is 1.8 Watts  and PowerSum = 24.2 Watts.
(Reflected Power should be <= 10% of PowerSum)

FSS:
It has been locked for 0 h and 18 min (should be days/weeks)
TPD[V] = 1.4V (min 0.9V)

ISS:
The diffracted power is around 11.7% (should be 5-9%)
Last saturation event was 0 h and 19 minutes ago (should be days/weeks)
H1 General
travis.sadecki@LIGO.ORG - posted 10:09, Monday 13 April 2015 (17839)
Morning meeting notes

HAM6 pumping continues, Kyle/Gerardo swapping annulus pumps

Jim working on updates ISI blend filters

CDS synchro/CPS work, vacuum maintenance for 3IFO, fiber installation between corner station and VPW

H1 SEI (ISC)
hugh.radkins@LIGO.ORG - posted 09:58, Monday 13 April 2015 (17838)
WHAM ISI Isolation Target Positions adjusted, again

Investigating the trip on WHAM6 CPS, Friday night.  Mirky for now.  See the output drives fairly high (solid 100s touching 1000 on OUTF mons) with saturaions totalized over the weekend.  Cleared these and saw a few more shortly.

Took ISI and HEPI down to review free hanging position.  HEPI Deltas (Free Hang-Servo position) pretty small except Rz w/ ~24urads.  The ISI too had a larger than we left it Friday shift in Rz.  Of course, HEPI Rz can not affect ISI Rz.  The ISI Rz shifted about 9urads from Friday.  Recall, on Friday we had 70urad shift on Rx.  Maybe further temperature and pressure shifts are settling out.  The Reference Target Positions were reset to match the free hanging location.  The loops close fine and the OUTF drives are as expected, markedly smaller.

If alignment in HAM6 is an issue, use HEPI first for horizontal changes to keep the ISI drive reduced.

H1 AOS
betsy.weaver@LIGO.ORG - posted 08:45, Monday 13 April 2015 - last comment - 12:13, Monday 13 April 2015(17836)
ETMx gain changed for some reason

Commissioners - SDF shows that someone changed the P and Y Damping gain on Thur April 9th.  I couldn't find why in the alog...  See attached.  This maybe should be restored...?

Images attached to this report
Comments related to this report
alexan.staley@LIGO.ORG - 12:13, Monday 13 April 2015 (17844)

I have restored these damping gains to the burt value since it was unclear why these were changed. Maybe this explains why our motion in the x-arm this weekend was not ideal.

H1 ISC (CAL)
evan.hall@LIGO.ORG - posted 01:11, Monday 13 April 2015 - last comment - 10:34, Monday 13 April 2015(17835)
15 W lock

Sheila, Alexa, Evan

Summary

We have recovered the usual low-noise locking state (except for the outstanding issue of the HAM6 centering scheme) and have turned up the power to 15 W.

Details

As before, HV in HAM6 has been turned off for the night.

Images attached to this report
Non-image files attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 10:34, Monday 13 April 2015 (17840)
The DARM Open Loop Gain comparison was made with the script
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Scripts/DARM_OLTFGTF_LHO_xx.m

Now that it has an aLOG number, I've moved and committed the analysis script to
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Scripts/DARM_OLTFGTF_LHO_LHOaLOG17835.m
and I've downloaded the template, and saved and committed it to
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Measurements/DARMOLGTFs/2015-04-13_H1_DARM_OLGTF_LHOaLOG17835.xml

Stay tuned for more detailed analysis -- so excited we've got data out to 1 [kHz]!

Other Notes:
- Evan used the above result to scale the optical gain of the sensing function in the CAL-CS front-end calibration. (This was after we suddenly had 50 [Mpc] for a bit -- the optical gain had not been correctly compensated for that lock stretch. It's now been fixed, but again, stay tuned for further analysis to confirm.)
- This model of the DARM loop -- which I just cleaned up and updated this Saturday (aLOG pending) -- do *not* include the either the analog or digital anti-imaging and anti-aliasing filters and includes a time delay or 440 [us], as was the case with the other case-by-case analysis scripts in that directory.
- as with LHO aLOG 17834, the ETMY ESD linearization is OFF.
H1 CAL
sheila.dwyer@LIGO.ORG - posted 21:44, Sunday 12 April 2015 - last comment - 10:39, Monday 13 April 2015(17834)
DARM OLG measurement with ETMY linearization off

Here is a measurement of the DARM OLG with the ETMY linearization off.  It isn't changed significantly from when the linearization was on (blue reference). 

Note:  the calibration is off tpnioght, we have changed the DARM offset but haven't corrected the calibration for this so at the moment our sensmon range is nonsense.  More details about todays locking coming later. 

Images attached to this report
Non-image files attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 10:39, Monday 13 April 2015 (17842)
I've saved and committed this DTT template to 
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/PreER7/H1/Measurements/DARMOLGTFs/2015-04-12_H1_DARM_OLGTF_LHOaLOG17834.xml

Stay tuned for further analysis. So happy to see data out to 1 [kHz]. Thanks much, Sheila!
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