Displaying reports 72761-72780 of 83105.Go to page Start 3635 3636 3637 3638 3639 3640 3641 3642 3643 End
Reports until 16:38, Monday 10 March 2014
H1 ISC
kiwamu.izumi@LIGO.ORG - posted 16:38, Monday 10 March 2014 (10661)
REFL_A commissioning

This is a report about a small task that has been in Daniel's commissioning calendar for a long time (see for example alog 10451).

I checked the signals of REFL_A and compared them with the in-air ones to check if they are functional.

The signal levels seem reasonable and therefore I conclude that REFL_A is functional without a problem. See below for more details.

 

Comparison of the signal level:

Before doing anything, I adjusted the demod phase of REFL_A_RF45 which had not been set to a useful number. It is now set to be 5 deg. This maximized the PRY signal in the in-phase output. On the other hand, REFL_A_RF9 seemed already good and therefore I didn't change the demod phase. Then I locked the PRY and injected a 10 Hz excitation in order to compare the responses between the in-vac and in-air ones using dtt. Note that I only used the in-phase signals as the q-phases don't really give a good signal in this situation. At the same time, the DC power on the PDs were measured to be 14200 cnts and 8020 cnts at REFL and REFLAIR respectively. This means that the in-vac one should show a higher response by a factor of 1.77 due to the difference in the power falling on the diodes.

Unfortunately, I wasn't able to figure our whether S1300533 or S1300534 is in HAM1. So for now I use transimpedance gain of 600 and 730 Ohms for 9 MHz and 45 MHz respectively which should give us a coarse estimation of the signal levels.

Expected and measured ratios of the 9 MHz detectors:

Expected and measured ratios of the 45 MHz detectors:

H1 TCS (TCS)
greg.grabeel@LIGO.ORG - posted 16:33, Monday 10 March 2014 (10660)
TCS mirror alignment check
Thomas Vo, Greg Grabeel
After hearing that LLO had an alignment problem with SM1 and SM2 Thomas and I decided to look and see if we could get a visual confirmation on alignment. Taking the opportunity given by a soft valve close, we stuck a camera up to the viewports and took some pictures. One set of pictures is through the regular glass, and the other are through the Zinc Selenide. The pictures are a little blurry from the long exposure time needed to get anything to stand out, but it looks like we are still good for having the test masses in sight. 
Images attached to this report
LHO General
justin.bergman@LIGO.ORG - posted 16:04, Monday 10 March 2014 (10658)
ops

800 - Karen to EY

904 - Fil and Aaron at EY most of the day workign on cabling

930 - Betsy,Kate,Margot working EY

940 - Arnaud meas ETMX

945 - Kyle Soft close GV7

945 - Kiwamu and Yuta re-aligning ISC Table at HAM2

1301 - HFD onsite

1310 - Corey and Hugh to ETMY with IAS

LHO VE
kyle.ryan@LIGO.ORG - posted 15:58, Monday 10 March 2014 (10657)
Began baking portable RGA assembly @ Y1-1 (started ~1100 hrs.)


			
			
LHO VE
kyle.ryan@LIGO.ORG - posted 15:56, Monday 10 March 2014 (10656)
Soft-cycled GV7 during crane activities


			
			
H1 ISC
kiwamu.izumi@LIGO.ORG - posted 13:03, Monday 10 March 2014 (10653)
ISCT1 realignment

Yuta and Kiwamu,

Since we changed the input pointing during the weekend (see alog 10637), we wanted to make sure that the alignment is still OK on ISCT1.

The beam was found to be off in both horizontally vertically by 5 mm or so everywhere in the REFL path. So we took this opportunity to realign everything, including the REFL and POP paths. Now the beam is all centered except for the top periscope mirrors which we can not easily see the surface.

After the realignment, we confirmed that the PRMI still locks.

H1 SEI (ISC, SEI)
jeffrey.kissel@LIGO.ORG - posted 12:51, Monday 10 March 2014 - last comment - 18:26, Monday 10 March 2014(10652)
resetting CPS targets

Jeff, Sheila

Last night when Jeff brought the ISIs back after trips due to the first earthquake, he reset the target offsets as we have discussed doing from now on. This moved ETMX ISI RZ (yaw) by 16urad on stage 1, 12 urad on stage 2, RY (pit for TMS) by 3 urad on stage 1, and 2 urad on stage 2. This is at least the third time that we have reset the target values for ETMX, and the second time we have seen a large move. (25 urad seen in RZ in alogs 10596 10602)

If we had changes of less than a urad, either our dither alingment or WFS would be able to correct for that, if we had changes of less than about 5 urad we would still be able to find the baffle PDs easily to recover the alignment.  20 urad though is difficult to recover from. I (Sheila) would prefer waiting for T240s to settle than doing a random walk in alignment over 10s of urad. 

We had a look at the other optics, and they don't seem to move that much. ITMX for example had no changes larger than 100nrad last night.

 

Comments related to this report
sheila.dwyer@LIGO.ORG - 14:38, Monday 10 March 2014 (10655)

It seems like the solution proposed by Brian of keeping RZ and RY for the ETMs would solve this, but here is a plot to show what is going on.

Images attached to this comment
sebastien.biscans@LIGO.ORG - 18:26, Monday 10 March 2014 (10665)

We did a model restart of all the BSC-ISIs last Tuesday. By doing that, we restored the old target values stored into the snap files.

On ETMX, these old target values were huge compare to the natural position of the ISI. That explains why, when we reset the targets yesterday after the earthquake, the new location of the ISI is so different than last week.

If you compare the location of the ISI now with the location BEFORE the model restart, you can see that the difference is way smaller (a little big on RZ and Z though).

Non-image files attached to this comment
H1 SYS
daniel.sigg@LIGO.ORG - posted 09:29, Monday 10 March 2014 (10648)
Commissioning calendar for next 2 weeks

Here is the list of commissioning task for the next 7-14 days:

Green team:

Red team:

Blue team (ALS WFS):

Blue team (ISCTEY):

TMS:

SEI/SUS team:

H1 SEI (INS)
hugh.radkins@LIGO.ORG - posted 07:53, Monday 10 March 2014 (10647)
WBSC10 ETMY SEI Activities and Status

Yesterday on Sunday, Mitchell and I got 6 of the 8 HEPI Actuators attached.  The remaining corner (NE#4) should fall by late morning Monday along with any alignment adjustment obvious from the Dial Indicators.  So far the DIs are looking pretty good as to alignment.  If IAS has its instruments at the ready, we should be complete by mid-day with post actuator install check/adjustments.

The ISI has a C3 cover on it so is not fit for TFs.  SUS and TMS should however feel free to do evaluate their systems.

H1 SEI (SUS)
kiwamu.izumi@LIGO.ORG - posted 07:27, Monday 10 March 2014 - last comment - 12:21, Monday 10 March 2014(10645)
watchdog recovery

I found that the most of the ISIs had been tripped. Probably it was due to the earthquake as logged by Jeff (alog 10638).

I untripped the following systems:

Currently I am having a trouble in engaging the Tcrappy blend filter on stage 2 of ITMX. I am leaving it with the simplest filter, i.e. "Start", for now.

Comments related to this report
kiwamu.izumi@LIGO.ORG - 07:30, Monday 10 March 2014 (10646)

And also IM3.

jeffrey.kissel@LIGO.ORG - 12:21, Monday 10 March 2014 (10651)
I had recovered the ISIs after the Earthquake I logged. There was another earthquake, 6.8 off the coast of california (see USGS Page) at 2014-03-10 05:18:13 UTC (5 hours later) that killed everything.
H1 ISC (ISC)
evan.hall@LIGO.ORG - posted 20:45, Sunday 09 March 2014 - last comment - 12:10, Wednesday 12 March 2014(10642)
PRC Length Measurement
(Evan H, Ed D, Stefan B and Dave O)(Evan H, Ed D, Stefan B and Dave O)
(Evan H, Ed D, Stefan B and Dave O)
 
We measured the length of the PRC by injecting the light from a 250 mW auxiliary NPRO (Lightwave) through the back of IM4 towards the PRM. The NPRO was phased locked to the main PSL carrier by observing the beat between these two lasers from the path IO_Forward using a New Focus 1811.
 
 
Phase Locking
 
The error signal was obtained by feeding the signal from the 1811 into the RF port of a double-balanced mixer. The LO of the mixer was driven with the source port of a network analyzer (HP4395A). The reulting IF was low-passed at 1.9 MHz and then fed into the input of a Newport LB1005 servo box. The settings on the box were 3kHz P-I corner, 50 dB low-frequency gain limit, and 4-0 on the gain knob. The output of this box was sent to the fast PZT input of the NPRO. The output was also attenuated by 4x10^-4, summed in with a DC trimpot voltage, and then and sent to the NPRO's slow temperature input. Once fast lock was acquired, the gain was increased until a small oscillation was observed, and then the gain was backed off. Then the LB1005 was switched from "LFGL" to "lock on", and the slow loop was switched on.
 
 
FSR Measurements
 
We measured the transfer function which takes the network analyzer's LO drive to REFLAIR_B_RF. The magnitude and phase of the this TF gives the complex reflectance function of the PRC. We measured over a series bands including 32.4 – 32.6 MHz, 68.8 – 69 MHz and 102.6 – 102.8 MHz. These bands were analysed when the auxiliary laser was locked above and below the PSL carrier.
 
The settings on the network analyzer were: sweep time of 500 s, 801 samples, IF bandwidth of 1kHz, and a span of 200 kHz.
 
Because of the sensitivity of the PLL servo, for each measurement we started the sweep on the network analyzer and then brought the auxiliary/PSL beat note into lock. Throughout these measurements, PRMI was sideband locked.
 
 
Results
 
We obtained the frequency response plots in the following order +102.7 MHz, +32.5 MHz, -32.5 MHz, -102.7 MHz (twice), -68.9 MHz, and +68.8 MHz.
 
Plots of the frequency response are attached. These magnitude data were fitted to a Lorentzian to determine the exact frequency of the resonances. The results were as follows:
 
FSR number    Resonance frequency              HWHM frequency
 
-39.5                102.701020 MHz +/- 180 Hz    26.7 kHz +/- 400 Hz
-39.5                102.700690 MHz +/- 190 Hz    27.3 kHz +/- 500 Hz
-26.5                68.900360 MHz +/- 150 Hz       24.0 kHz +/- 400 Hz
-12.5                32.499990 MHz +/- 90 Hz         20.56 kHz +/- 180 Hz
12.5                 32.501860 MHz +/- 90 Hz         20.5 kHz +/- 200 Hz
26.5                 68.904100 MHz +/- 170 Hz       25.3 kHz +/- 400 Hz
39.5                102.705400 MHz +/- 190 Hz     29.2 kHz +/- 500 Hz
 
Already from these numbers we can see that the PSL carrier does not appear to be perfectly antiresonant; there is an offset of about 1400 Hz. Note also there is a systematic disagreement in the numbers for the HWHM frequency. Taking a nominal value of 25 kHz for the HWHM and 2.6 MHz for the FSR gives a finesse of 50.
 
We then plotted these with FSR number on the horizontal axis and resonance frequency on the vertical axis. The residuals do not show a random behaviour; there appears to be additional structure not captured in this model. The slope of the line gives the FSR of the PRC, and the offset is 1400 Hz +/- 300 Hz, indicating the offset from antiresonance.
 
At the present time we can say that the FSR of the PRC is 2.600075 MHz +/- 26 Hz. This corresponds to a PRC length of 57.651 m +/- 1 mm. This measurement is limited by our residuals, and we are currently investigating this.
 
In estimating the uncertainty in the FSR, we note that the largest residual is for the 102.7 MHz measurement, and is equal to about 1 kHz. This fractional uncertainty is 1x10^-5; using this as the fractional uncertainty on the FSR gives 26 Hz. This dominates over the purely statistical error given by the fitting algorithm (11 Hz). Propagating this 26 Hz uncertainty forward to the PRC length gives 57.6507 m +/- 0.6 mm. To be conservative, we quote the uncertainty to the nearest 1 mm.
We measured the length of the PRC by injecting the light from a 250 mW auxiliary NPRO (Lightwave) through the back of IM4 towards the PRM. The NPRO was phased locked to the main PSL carrier by observing the beat between these two lasers from the path IO_Forward using a New Focus 1811.
 
 
Phase Locking
 
The error signal was obtained by feeding the signal from the 1811 into the RF port of a double-balanced mixer. The LO of the mixer was driven with the source port of a network analyzer (HP4395A). The reulting IF was low-passed at 1.9 MHz and then fed into the input of a Newport LB1005 servo box. The settings on the box were 3kHz P-I corner, 50 dB low-frequency gain limit, and 4-0 on the gain knob. The output of this box was sent to the fast PZT input of the NPRO. The output was also attenuated by 4x10^-4, summed in with a DC trimpot voltage, and then and sent to the NPRO's slow temperature input. Once fast lock was acquired, the gain was increased until a small oscillation was observed, and then the gain was backed off. Then the LB1005 was switched from "LFGL" to "lock on", and the slow loop was switched on.
 
 
FSR Measurements
 
We measured the transfer function which takes the network analyzer's LO drive to REFLAIR_B_RF. The magnitude and phase of the this TF gives the complex reflectance function of the PRC. We measured over a series bands including 32.4 – 32.6 MHz, 68.8 – 69 MHz and 102.6 – 102.8 MHz. These bands were analysed when the auxiliary laser was locked above and below the PSL carrier.
 
The settings on the network analyzer were: sweep time of 500 s, 801 samples, IF bandwidth of 1kHz, and a span of 200 kHz.
 
Because of the sensitivity of the PLL servo, for each measurement we started the sweep on the network analyzer and then brought the auxiliary/PSL beat note into lock. Throughout these measurements, PRMI was sideband locked.
 
 
Results
 
We obtained the frequency response plots in the following order +102.7 MHz, +32.5 MHz, -32.5 MHz, -102.7 MHz (twice), -68.9 MHz, and +68.8 MHz.
 
Plots of the frequency response are attached. These functions were fitted to a simple cavity model to determine the exact frequency of the resonances. The results were as follows:
 
FSR number    Resonance frequency
 
-39.5         102.701020 MHz +/- 180 Hz
-39.5         102.700690 MHz +/- 190 Hz
-26.5         68.900360 MHz +/- 150 Hz
-12.5         32.499990 MHz +/- 90 Hz
12.5          32.501860 MHz +/- 90 Hz
26.5          68.904100 MHz +/- 170 Hz
39.5          102.705400 MHz +/- 190 Hz    
 
Already from these numbers we can see that the PSL carrier does not appear to be perfectly antiresonant; there is an offset of about 1400 Hz.
 
We then plotted these with FSR number on the horizontal axis and resonance frequency on the vertical axis. The residuals do not show a random behaviour; there appears to be additional structure not captured in this model.
 
At the present time we can say that the FSR of the PRC is 2.600075 MHz +/- 26 Hz. This corresponds to a PRC length of 57.6507 m +/- 0.6 mm. This measurement is limited by our residuals, and we are currently investigating this.
Non-image files attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 11:28, Monday 10 March 2014 (10650)

Assuming the frequency calibration of the network analyzer is accurate, we can compare the measured PRC length with the measured mode cleaner length. This was measured in alog 9679.

Parameter Value Unit
FSRPRC 2.600075 MHz
LPRC 57.6508 m
FSRMC 9.099173 MHz
LMC 16.473612 m
FSRMC / 3.5 - FSRPRC -306 Hz
(1 - FSRMC / 3.5 FSRPRC) LPRC 6.8 mm

Compared with the modeclaner, the power recycling cavity is about 7 mm too short. The other way around, the modecleaner is about 2 mm too long.

daniel.sigg@LIGO.ORG - 13:58, Monday 10 March 2014 (10654)

We hooked up the network analyzer to the timing comparator/frequency counter and set it to 40 MHz sharp at 0 dBm. The readback value was dead on, occasionally we would read 1 Hz higher. Conclusion: the frequency of the sweep is no more than 1 Hz off, even at 100 MHz.

evan.hall@LIGO.ORG - 12:10, Wednesday 12 March 2014 (10713)

I've redone the fits using both the magnitude and the phase. The fitting function is now the usual Fabry–Pérot reflectance function, with a complex magnitude to allow for global amplitude rescaling and global phase offset.

Nominal FSR Frequency (Hz)
−39.5 −102 701 040 ± 200
−39.5 −102 700 900 ± 220
−26.5 −68 900 600 ± 180
−12.5 −32 500 080 ± 100
12.5 32 501 720 ± 110
26.5 68 903 940 ± 200
39.5 102 704 700 ± 200

The linear fit now gives an FSR of (2 600 073 ± 9) Hz. This is consistent with the previous fit, and anyway the total error is still dominated by some systematic, as seen by the fact that the residuals are excessively large.

Taking a systematic 400 Hz uncertainty on the residual for the 12.5 FSR measurement gives a systematic uncertainty of 32 Hz on the PRC FSR. Propagating foward gives (57.6508 ± 0.0007) m.

Non-image files attached to this comment
H1 SEI
jeffrey.kissel@LIGO.ORG - posted 20:08, Sunday 09 March 2014 (10641)
Leaving BSC-ISIs with ST1 ON, and ST2 OFF
J. Kissel

As of 2014-03-10 03:00 UTC (08:00p PT), I've left the functional BSC-ISIs in the following state:
          ITMY                 BS                  ITMX                 ETMX
       Iso       Blend   | Iso      Blend   | Iso       Blend   | Iso       Blend   |
HPI    Lvl 1     "Pos"   | Lvl 1    "Pos"   | Lvl 1     "Pos"   | Lvl 1     "Pos"   | 
ST1    Lvl 3   "TCrappy" | Lvl 2* "TCrappy" | Lvl 3   "TCrappy" | Lvl 3   "TCrappy" |
ST2    OFF               | OFF              | OFF               | OFF 

I left ST2 OFF, because I want to get a measure for the differences between chamber performance is as related to the differing input motion at low frequency. Unfortunately, the ISI BS's level 3 controller appears to be unstable, so I had to stick with Level 2, but this shouldn't matter for the regions I'm looking to study. I've also made sure all optical levers are aligned.
H1 SEI (ISC, SUS, SYS)
jeffrey.kissel@LIGO.ORG - posted 19:15, Sunday 09 March 2014 (10640)
Ground, HEPI Pier, and ST1 ISI Motion During 2014-03-06 High Winds
J. Kissel

I've grabbed spectra from all possible degrees of freedom of the ground, HEPI pier, and ISI ST1 for the four operational ground sensors and the four operational BSC-ISIs during a very windy and noisy afternoon this past Thursday, Mar 6 2014 at 22:15 UTC. This will hopefully assist modelling efforts to design blend filters that might be able to withstand such input noise. Unfortunately, because Sebastien was commissioning a few chambers, and we had to reboot ETMX to get his GND T240 stored in the right place, there wasn't any long stretch of time during that day in which all platforms were at comparable performance (hence the differences in the ISI ST1 performance). Also, I'm not sure I believe what the rotational HEPI L4Cs are saying at the microseism.

The spectra are attached, but they were created by the following DTT templates,
/ligo/svncommon/SeiSVN/seismic/BSC-ISI/H1/Common/Data/
2014-03-06_2215UTC_GroundMotion_ASDs.xml
2014-03-06_2215UTC_HEPIPierMotion_ASDs.xml
2014-03-06_2215UTC_ISIST1Motion_ASDs.xml
and they were also exported to the following files
/ligo/svncommon/SeiSVN/seismic/BSC-ISI/H1/Common/Data/
2014-03-06_2215UTC_Windy_GroundMotion_ASDs_ITMY-XYZ_HAM2-XYZ_HAM5-XYZ_ETMX-XYZ.txt
2014-03-06_2215UTC_Windy_ISIST1Motion_ASDs_BS-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_ISIST1Motion_ASDs_ETMX-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_ISIST1Motion_ASDs_ITMX-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_ISIST1Motion_ASDs_ITMY-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_PierMotion_ASDs_BS-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_PierMotion_ASDs_ETMX-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_PierMotion_ASDs_ITMX-XYZRXRYRZ.txt
2014-03-06_2215UTC_Windy_PierMotion_ASDs_ITMY-XYZRXRYRZ.txt
where the last part of the file name indicates the order in which the channels have been exported.
Non-image files attached to this report
H1 ISC
sheila.dwyer@LIGO.ORG - posted 15:58, Sunday 09 March 2014 - last comment - 07:20, Monday 10 March 2014(10637)
PRMI+X arm alingment

Yuta, Sheila, Alexa

Today we found an alignment that should be acceptable to both PRMI and the Xarm, in the hopes that the green team and red team will not each have to change PR2 significantly each day. 

First Yuta aligned PRX, then we aligned the Xarm, locked the IR to the X arm, and moved PR2 and IM4 to point the beam down the xarm.  After this the alignment of PRX was way off and unlockable.  We checked that the beam was centered on POPAir B, then restored PR2 to the intial PRX alignment.  Then Yuta aligned PRM by hand, and walked PR2 back to the arm alignment. Finally Yuta realinged PRY.  A screenshot of the final positions is attached.

Yuta has changed the dither guardian script for PRX so that the PR2 dither is now fed back to PRM instead of PR2. 

Hopefully this means that the PRMI and arm alignments will stay compatable and both the red team and green team don't have to spend as much time aligning each day. 

Images attached to this report
Comments related to this report
kiwamu.izumi@LIGO.ORG - 07:20, Monday 10 March 2014 (10644)

Just an observation from this morning:

I wanted to see how much power build up the PRC can achieve without touching the alignment. I reverted PRM, BS and ITMY to the values that Sheila had in her screen shot because their alignment wasn't saved and they had come back to some past values by the guardian. The highest build up I saw was about 12 uW in POPAIR_B_RF18 which is about 6-7 times smaller than the highest in the past. Not bad.

Note that ITMX, ETMX and TMXS had different alignment biases than that in the screen shot. I assumed that there had been a fine touch by the green team and I didn't revert them to the screen shot values. The green light mostly stays on a 01 mode and occasionally on a 00 mode.

H1 SUS
arnaud.pele@LIGO.ORG - posted 12:32, Friday 07 March 2014 - last comment - 01:29, Monday 10 March 2014(10607)
ETMX and ITMX PUM measurements

Yesterday night and this morning some diagonalization measurements were taken with pum drive on etmx and itmx. The low coherence for the pitch drive described on the previous alog was due to the optic not centered enough on the oplev, so both ETMX p2p and y2y were remeasured. Those measurements can actually be really fast (15/20min each).
ITMX measurement has some calibration factor of 1.56 for Yaw and 1.83 in Pitch. T1100378 was the reference for calibrating the drive from cts to N.

Attached are the plots comparing the measurement and the model (wirerehang for itmx, fiber for etmx). Note that there is a sign error in ETMX Yaw, so we should double check if that comes from the Oplev sign convention.
 

ITMX : /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ITMX/SAGL2/Results/quad_{p2p/y2y}.mat

ETMX : /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMX/SAGL2/Results/quad_{p2p/y2y.mat

ITMX : /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ITMX/SAGL2/Data/2014-03-06_H1SUSITMX_{P2PY/Y2PY}_WhiteNoise.xml

ETMX : /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ITMX/SAGL2/Data/2014-03-04_H1SUSETMX_{P2PY/Y2PY}_WhiteNoise.xml

ITMX : /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ITMX/SAGL2/Scripts/itmx_L2_diag.m

ETMX : /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMX/SAGL2/Scripts/etmx_L2_diag.m

Images attached to this report
Comments related to this report
keita.kawabe@LIGO.ORG - 15:26, Friday 07 March 2014 (10610)

PUM drivealign P2P and Y2Y filters were installed.

In each of the attached, foton screen shot to the left shows the actual filter installed, matlab plot to the right shows the P2P or Y2Y measurement, fit, model, and the expected TF from PUM to the test mass after the new filter takes effect.

As you see I made the filters such that ITM and ETM looks as if they share the same low Q (Q=3) resonance at 0.51 Hz for PIT and 0.6Hz for YAW. There's also a roll of at 30Hz, which is not that aggressive. If necessary you can easily add more.

I ignored the DC calibration of the measurement. I'll handle them in the gain.

The filters relevant are FM1 of H1:SUS-ETMX_L2_DRIVEALIGN_P2P, Y2Y and corresponding ITMX filters.

Scripts used for the fit and inversion as well as the filter definition files generated by the scripts are:

~controls/keita.kawabe/fit/[EI]XPUM_[PY]2[PY]fit.m

~controls/keita.kawabe/fit/[EI]XPUM_[PY]2[PY]inversion_soscoeffs.txt

Images attached to this comment
arnaud.pele@LIGO.ORG - 01:29, Monday 10 March 2014 (10643)

[Yuta Keita Arnaud]

ETMX ITMY ITMX top mass P2P drivealign filters installed

On friday, filters were designed the same way as Keita, in order to get a single pendulum transfer function from the top mass drive to the test mass displacement in pitch. The filters were installed in the top drivealign matrix in FM1 of the P2P bank filter. ITMX filter is a copy paste from ITMY, assuming they have the same P2P transfer function (both are wires). Attached are the plots showing the design of the filters and the foton version. The transfer function after filtering has its cut off frequency at 0.45Hz for ETMX and 0.55Hz for ITMY/ITMX.

ETMX Length to pitch decoupling was also designed and installed in L2P drivealign matrix. Plots of design pending.

Images attached to this comment
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