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CAL (General)
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darkhan.tuyenbayev - 08:03, Friday 03 April 2020 (13963)Get code to link to this report
DARM transfer function measurements April 2-3

YamamotoT, Darkhan,

We took a set of DARM transfer function measurements on the April 2-3 calibration day.

Actuation levels of DARM, XARM, YARM excitations were adjusted (lowered) to avoid saturating the TM coil driver actuators. Actuation levels of PCALX and PCALY excitations were lowered to avoid breaking the OFS loops.

The anaysis of the measurements will be posted at a later time.

Images attached to this report
13963_20200403010206_screenshotfrom20200403074808.png 13963_20200403010212_screenshotfrom20200403074948.png 13963_20200403010216_screenshotfrom20200403075119.png 13963_20200403010222_screenshotfrom20200403075212.png 13963_20200403010227_screenshotfrom20200403075329.png
MIF (General)
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takaaki.yokozawa - 07:54, Friday 03 April 2020 (13962)Get code to link to this report
Comment to One of IFO lock status (Click here to view original report: 13961)

Picture with ITM TCam image

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13962_20200403005405_screenshotfrom20200403074249.png
MIF (General)
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shinji.miyoki - 07:10, Friday 03 April 2020 (13961)Get code to link to this report
One of IFO lock status
I attached one of IFO lock status from around 5:30 to 7:00.

The initial alignment with which we can obtain highest transmitting power for both arms started decreasing just after the locking and seemed to go some constant level as attached files.

ETMY Yaw drift was about 5 micro radian.
ETMY Pitch drift was about 3 micro radian.

SR3 Yaw drift was about 2 micro radian.
PR3 Yaw drift was about 2 micro radian.

Around 5:30 (TMSXY values are max), just after locking about 460 kpc was indicated.
Around 7:15 (TMSX values are about 105/125 for X, 85/100 for Y, compared with the max values just after locking), 595kpc was indicated, however, we should consider the reduction of the optical gain.
Images attached to this report
13961_20200403000940_xarm.png 13961_20200403000945_yarm.png
Comments related to this report
takaaki.yokozawa - 07:54, Friday 03 April 2020 (13962)

Picture with ITM TCam image

MIF (ASC)
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masayuki.nakano - 01:05, Friday 03 April 2020 (13960)Get code to link to this report
ETM ADS yaw loop

The ADS yaw loop was closed. Dither frequency is 4.6 Hz for ETMX and 11.3 Hz for ETMY. It seems to be working well.

Images attached to this report
13960_20200402180444_screenshotfrom20200402234158.png 13960_20200402180503_screenshotfrom20200402234240.png
VIS (General)
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masayuki.nakano - 01:01, Friday 03 April 2020 (13959)Get code to link to this report
Comment to Add RAMPHOLD block in Type-A models (Click here to view original report: 13957)

The ISCWD is working well. The functionality of this watchdog is as follows:

  • This watchdog is monitoring the input to the ISC INF from the LSC block and the ASC block including the ADS and BPC. If these signals get beyond the threshold, immediately the feedback signal of the ISC will be held by the new RAMPHOLD block.
  • If the reset pulse is sent, the RAMPHOLD block will release the output with the ramp time as shown in klog13937
  • The VIS guardian will turn off the ISCINF just after the watchdog tripped, and reset the watchdog.
  • It working well, and the kick of the suspension got small thanks for this WD.
Images attached to this comment
13959_20200402180256_screenshotfrom20200403010116.png
AOS (Optical Levers)
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shinji.miyoki - 00:51, Friday 03 April 2020 (13958)Get code to link to this report
Comment to Surgery of the IMMT2's oplev (Click here to view original report: 13942)
One additional info.
A beam dumper for a beam reflected on QPD was also put btw KG5 and a window (IR filter).
VIS (General)
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kouseki.miyo - 21:08, Thursday 02 April 2020 (13957)Get code to link to this report
Add RAMPHOLD block in Type-A models

Nakano, Miyo

We add ISCRAMPHOLD block in Type-A suspensions. 

We modified TM, IM, and MN master model of Type-A in userapps/vis/common/models .
The new block is added in userapps/sys/common/models/KAGRA_UTIL.mdl.

Now, SVN version is 2937. 

Detail information about this modification will poseted by Nakano-san later.

Comments related to this report
masayuki.nakano - 01:01, Friday 03 April 2020 (13959)

The ISCWD is working well. The functionality of this watchdog is as follows:

  • This watchdog is monitoring the input to the ISC INF from the LSC block and the ASC block including the ADS and BPC. If these signals get beyond the threshold, immediately the feedback signal of the ISC will be held by the new RAMPHOLD block.
  • If the reset pulse is sent, the RAMPHOLD block will release the output with the ramp time as shown in klog13937
  • The VIS guardian will turn off the ISCINF just after the watchdog tripped, and reset the watchdog.
  • It working well, and the kick of the suspension got small thanks for this WD.
MIF (General)
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takafumi.ushiba - 19:29, Thursday 02 April 2020 (13956)Get code to link to this report
Alignment recorder guardian modification

[Akutsu, Nakano, Yamamoto, Ushiba]

We modified the alignment recording guardian.
If we requested PRFPMI_RECORDING to ALIGNMENT_RECODER guardian, IMMT2, all PRs, all test masses, SR3, and SR2 good OpLev value is recorded only when alignment is good.

Restore OL set point, OFFLOAD_PRFPMI state, also implemented but not tested yet.
I will test it tomorrow morning.

MIF (ASC)
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takafumi.ushiba - 19:07, Thursday 02 April 2020 (13955)Get code to link to this report
ADS progress for both ETMs

[Lucia, Ushiba]

In this morning, we tried to close the ADS loop  for YAW of ETMX and ETMY.
First, we saw the signals of OpLevs, TRX, and TRY.
Then, we found that ETMY YAW excitation excited ETMY PIT at the same time and PIT motion at this frequency is larger than YAW.
So, we started from optimization of drive align matrix.

However, even though we scaned enogh large range for Y2P matrix value, we couldn't find good values for diagonalization.
We don't know exact reason but maybe due to the resonance or damping filter, the phase of between PIT and YAW motion is not 0 or 180 degrees.
So, we gave up drive align matrix optimization.

What we can do is as follows:
1.Using higher frequenies for dither excitation.
2.Using TM OpLev set point to excite the Yaw motion.

We tok over he work to Nakano-kun.

MIF (General)
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masayuki.nakano - 16:49, Thursday 02 April 2020 (13954)Get code to link to this report
Comment to Power at TMSX IR PDA1 reduced about half (Click here to view original report: 13945)

I changed the FM1 so that the single arm TRANS got 1 at the FB output when the main laser power is 3.6 W.

Images attached to this comment
13954_20200402094931_screenshotfrom20200402164818.png
MIF (General)
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tomotada.akutsu - 16:14, Thursday 02 April 2020 (13953)Get code to link to this report
Comment to alignment log last night (4/1) - information when you lose arm flashes completely (Click here to view original report: 13952)

non

MIF (General)
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keiko.kokeyama - 15:45, Thursday 02 April 2020 (13952)Get code to link to this report
alignment log last night (4/1) - information when you lose arm flashes completely

[Miyoki, Akutsu, Kokeyama]

Because of the VIS offload campaign in daytime, the alignment was completely off for Y arm. This log may be useful when you completely lose an arm alignment.

  • Last night X arm and Vertex were restored without any problem. Y arm was completely lost.
  • For Y arm, the cavity flash did not recovered even oplev values restored for SR3, IY, and EY. First, to find the GR flash, we used IY telephoto camera to find the single spot from SR3.
  • Note that EY camera was not useful for the initial aliugnment: it was too slow and too dark to see a single bounce. The time stamp is not right to the shown image, either.
  • Then, align EY so that the reflection spot from EY can be found on the IY camera. 
  • Adjust EY, IY, SR3 by looking at the GR TR level and also the spot positions on the IY camera. EY camera can be used when flashes are good.
  • Request Y arm guardian to "IR LOCK." It should lock IR.
  • Align IR beam by BS, looking at the IR TRANS level.
  • Check the spot positions for IR. Also again GR spots.
  • Repeat the procedure if necessary.

After this, Yokozawa-san and Yuzu-san kindly took over (for the initial alignment lecture) at 3am.

Comments related to this report
tomotada.akutsu - 16:14, Thursday 02 April 2020 (13953)

non

AOS (Optical Levers)
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keiko.kokeyama - 15:28, Thursday 02 April 2020 (13951)Get code to link to this report
Comment to Surgery of the IMMT2's oplev (Click here to view original report: 13942)

Here are cartoon summaries:

Attach 1 (top) - When the initial installation (probably)
Attach 1 (bottom) - On Apr 1, 2020, before the reapir (while entire commissioning so far)
Attach 2 - After repair.
 

Images attached to this comment
13951_20200402082833_1p1.png 13951_20200402082838_1p2.png
MIF (General)
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takashi.uchiyama - 08:24, Thursday 02 April 2020 (13950)Get code to link to this report
Comment to Tcam for IY or IX (Click here to view original report: 13929)

Yokozawa-Sama fixed it.
IOO (Laser Bench)
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shinji.miyoki - 08:03, Thursday 02 April 2020 (13949)Get code to link to this report
Comment to PMC aligned (Click here to view original report: 13934)
So, we will got more than 1.16 times power for IFO. It is important to get more sensitivity at present.
CAL (General)
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yuki.inoue - 04:21, Thursday 02 April 2020 (13948)Get code to link to this report
Comment to ETMX and ETMY TM coil driver transfer function measurements April 1 (Click here to view original report: 13946)
Hi all,

I analyzed the measured data.
The results are following:

https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11587
DAS (General)
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takaaki.yokozawa - 01:29, Thursday 02 April 2020 (13947)Get code to link to this report
Betelgeuse V band

Betelgeuse V band

Images attached to this report
13947_20200401182945_29.png
CAL (General)
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darkhan.tuyenbayev - 00:21, Thursday 02 April 2020 (13946)Get code to link to this report
ETMX and ETMY TM coil driver transfer function measurements April 1

YamamotoT, TomaruT, Darkhan,

Today (April 1) we measured the TM stage coil driver transfer functions at the X-End and Y-End.

Transfer functions of four channels of the TM chassis were measured in three different states:

  • no low-pass filters (LP) switched on
  • only the first stage LP turned on
  • only the third stage LP turned on

When analyzing the TFs the corresponding reference measurement must be divided out. Reference TFs were measured by connecting the output from the BNC-to-DB9 interface board to the input of DB9-to-BNC interface board. So, reference TFs take into account the 2x gain factor and possible non-flat responses of the interface boards and the spectrum analyzer.

Measurement info and data format:

Excitation level  : 0.5 V
Number of averages: 5
Frequency vector  : same for all measurements (in files *.X): log-spaced 0.1 Hz - 51.2 kHz

States:

State 0 (CH#ST0A.TXT, CH#ST0P.TXT, CH#ST0V1.TXT, CH#ST0V2.TXT): all low-pass filters (LP) switched off
State 2 (CH#ST2A.TXT, etc.): only the first stage LP is turned on
State 6 (CH#ST6A.TXT, etc.): only the third stage LP is turned on

Data format:

Magnitude             (REF#A.TXT  and CH#ST0A.TXT)  : dbMag
Phase                 (REF#P.TXT  and CH#ST0P.TXT)  : degrees
CH1 (input) Norm Var  (REF#V1.TXT and CH#ST0V1.TXT) : LinMag
CH2 (output) Norm Var (REF#V2.TXT and CH#ST0V2.TXT) : LinMag

Measurement data was saved in

Comments related to this report
yuki.inoue - 04:21, Thursday 02 April 2020 (13948)
Hi all,

I analyzed the measured data.
The results are following:

https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11587
MIF (General)
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keiko.kokeyama - 23:54, Wednesday 01 April 2020 (13945)Get code to link to this report
Power at TMSX IR PDA1 reduced about half

[Akutsu, Miyoki, Kokeyama]

50/50 BS was placed in front of the TMSX IR PD. The power was reduced for a factor of 0.43.

In MEDM, which gain to change, FM1 (name "1.7W") or GAIN (now 3.16) of K1:AOS-TMSX_IR_PDA1??

Comments related to this report
masayuki.nakano - 16:49, Thursday 02 April 2020 (13954)

I changed the FM1 so that the single arm TRANS got 1 at the FB output when the main laser power is 3.6 W.

AOS (Optical Levers)
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tomotada.akutsu - 22:51, Wednesday 01 April 2020 (13943)Get code to link to this report
A QPD assembly was detached and stocked

Related to 13942; a QPD assembly for IMMT2T (IR transmission from IMMT2) was detached and stocked in a black strage for AOS located between the PR3 chamber and PR2 chamber.

By the way, the QPD circuit was not fully fixed to the support structure!! The four M4 screws to fix the QPD circuit were loosen somehow... OMG!

Images attached to this report
13943_20200401155006_img3177.jpg 13943_20200401155013_img3178.jpg